Factors in adult health-related quality of life: a population-based study

Daniele Durães Noronha Andréa Maria Eleutério de Barros Lima Martins Diego dos Santos Dias Marise Fagundes Silveira Alfredo Maurício Batista De Paula Desirée Sant Ana Haikal About the authors

Abstract

This study aimed to investigate factors associated with the physical health components (PHC) and mental health components (MHC) of health-related quality of life in adults. It is a population-based study, with household cluster sampling. The dependent variables were the PHC and MHC scores in the 12-Item Short-Form Health Survey (SF-12); the independent variables were social-demographic characteristics relating to health and behaviors. A multiple regression was made by the General Linear Model. Of the 841 interviewees, 31% had PHC adversely affected, and 37.2% had MHC adversely affected; 57% had adverse score in at least one domain. The average scores were 49.9 for the physical health component and 47.1 for the MHC. Higher scores on the PHC were associated with: being male (β = 1.94), having a car in the family (β = 0.89), having recently used dental services (β = 1.86), not having a chronic disease (β = 4.60), not using any medication (β = 2.09), not being a smoker (β = 2.04) and practicing physical activities (β = 1.73). Higher scores on the MHC were associated with not using medication (β = 1.91) and not being a smoker (β = 1.26). There is a need for further studies and policies aimed at maintaining and/or recovery of the physical and mental wellbeing of adults without specific diseases.

Quality of life; Adult; Health profile; Population surveys

Introduction

The World Health Organization (WHO)11. The WHOQOL Group. The World Health Organization quality of life assessment (WHOQOL): position paper from the World Health Organization. Soc Sci Med 1995; 41(10):1403-1409. defines Quality of Life (QOL) as “the individual’s perception of his own position in life in the context of the culture and value systems in which he lives and in relation to the related objectives, expectations, standards and concerns”. Since this is a dynamic, wide-ranging, subjective and polysemic concept22. Ferrans CE. Development of a conceptual model of quality of life. Sch Inq Nurs Pract 1996; 10(3):293-304., various terms have been used in the literature to define QOL, such as well-being33. Guyatt GH, Feeny DH, Patrick DL. Measuring health-related quality of life. Ann Intern Med 1993; 118(8):622-629., degree to which people take advantage of the possibilities of their lives44. Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004., perception of satisfaction with life22. Ferrans CE. Development of a conceptual model of quality of life. Sch Inq Nurs Pract 1996; 10(3):293-304.. The broad dimension of health and its relationship with various positive and negative aspects of life allow for various different forms of assessment, leading individuals with the same illnesses to manifest different levels of physical and/or emotional health and wellbeing. Based on these questions and on the multidimensional nature of QOL, the concept of Health-related Quality of Life (HRQOL), developed, and also a proliferation of instruments to measure it33. Guyatt GH, Feeny DH, Patrick DL. Measuring health-related quality of life. Ann Intern Med 1993; 118(8):622-629..

The instruments of HRQOL, created to transform subjective feelings into marks that were able to undergo measurement and objective analysis, have been used in the literature in recent years, although some are considered to be very extensive and/or complex for application and analysis. Commonly the instruments to measure HRQOL present questions divided into groups (also called domains or components), and aim to evaluate some specific aspects of limitation of health and wellbeing44. Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004.,55. Ware JE, Kosinski M, Keller SD. A 12-item short-form health survey: construction of scales and preliminary tests of reliability and validity. Med Care 1996; 34(3):220-233.. Among the instruments most used, we may highlight the World Health Organization Quality of Life Assessment (WHOQOL), the Medical Outcomes Study 36-Item Short Form (SF-36) and the 12-Item Short-Form Health Survey (SF-12)44. Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004.. The latter is internationally recognized and widely used in assessment of HRQOL in population studies, due to its being short, understandable, able to monitor outcomes in health in both general and specific populations55. Ware JE, Kosinski M, Keller SD. A 12-item short-form health survey: construction of scales and preliminary tests of reliability and validity. Med Care 1996; 34(3):220-233., and having satisfactory psychometric properties66. Silveira MF, Almeida JC, Freire RS, Haikal DS, Martins AEBL. Propriedades psicométricas do instrumento de avaliação da qualidade de vida: 12-item health survey (SF-12). Cien Saude Colet 2013; 18(7):1923-1931.. It provides summary scores for the physical health component (PHC) and the mental health component (MHC) of the HRQOL.

Prior studies have evaluated the HRQOL in specific populations, normally institutionalized populations and/or populations with some chronic disease, including prostate cancer77. Song L, Mishel M, Bensen JT, Chen RC, Knafl GJ, Blackard B, Farnan L, Fontham E, Joseph Su L, Brennan CS, Mohler JL, Godley PA. How does health literacy affect quality of life among men with newly diagnosed clinically localized prostate cancer? Findings from the North Carolina-Louisiana Prostate Cancer Project (PCaP). Cancer 2012; 118(15):3842-3851., advanced stage cancer88. Rouanne M, Massard C, Hollebecque A, Rousseau V, Varga A, Gazzah A, Neuzillet Y, Lebret T, Soria JC. Evaluation of sexuality, health-related quality-of-life and depression in advanced cancer patients: a prospective study in a Phase I clinical trial unit of predominantly targeted anticancer drugs. Eur J Cancer 2013; 49(2):431-438., sickle cell anemia99. Menezes ASOP, Len CA, Hilário MOE, Terreri MTRA, Braga JAP. Qualidade de vida em portadores de doença falciforme. Rev paul pediatr 2013; 31(1):24-29., liver disease1010. Svirtlih N, Pavic S, Terzic D, Delic D, Simonovic J, Gvozdenovic E, Boricic I. Reduced quality of life in patients with chronic viral liver disease as assessed by SF12 questionnaire. J Gastrointestin Liver Dis 2008; 17(4):405-409., generalized chronic pain1111. Nicholl BI, Macfarlane GJ, Davies KA, Morriss R, Dickens C, McBeth J. Premorbid psychosocial factors are associated with poor health-related quality of life in subjects with new onset of chronic widespread pain – Results from the EPIFUND study. Pain 2009; 141(1-2):119-126., people undergoing hemodialysis1212. Lopes GB, Martins MTS, Matos CM, Amorim JL, Leite EB, Miranda EA, Lopes AA. Comparações de medidas de qualidade de vida entre mulheres e homens em hemodiálise. Rev Assoc Med Bras 2007; 53(6):506-509., and others. However, there is a great scarcity of studies on HRQOL conducted among adults of the population in general who do not have any specific pathology and are not institutionalized – although there is an increasing recognition of the importance of generating data related to health and HRQOL of this population stratum. Adults are the majority of the population, they demand health services, they have epidemiological particularities, and, because they are mostly workers, their conditions of health and wellbeing can have an important economic and social effect, both in the context of the family and in the economy of the country1313. Pinto VG. Saúde bucal coletiva. 4ª Edição. São Paulo: Editora Santos; 2000.,1414. Reisine ST, Bailit HL. Clinical oral health status and adult perceptions of oral health. Soc Sci Med Med Psychol Med Sociol 1980; 14A(6):597-605.. Also, adults have a decisive influence in the behavior of their dependents and, by this route, patterns of behavior and lifestyles adopted between adults1313. Pinto VG. Saúde bucal coletiva. 4ª Edição. São Paulo: Editora Santos; 2000., such as the consumption of tobacco or alcoholic drinks, and practice of physical activities, as well as influencing the level of potential for disease in the medium and long term, can have consequences for future generations.

In this context, this study investigated, using the SF-12, the PHC and MHC of the HRQOL, and its association with social-demographic characteristics, in relation to health and behaviors in a representative sample of adults of the community, that is to say, people who are not institutionalized and are not suffering from specific systemic conditions.

Methodology

This was an analytical cross-sectional study conducted on adults aged 35 to 44 in the municipality of Montes Claros, considered to be the principal city of the north of the Brazilian State of Minas Gerais – which, for this reason, has the characteristics of a regional capital, with a radius of influence that includes the whole of the north of the State of Minas Gerais and part of the south of Bahia. In 2013, the Brazilian Geography and Statistics Institute (IBGE) estimated its population at 385,8981515. Instituto Brasileiro de Geografia e Estatística (IBGE). Estimativas populacionais para os municípios brasileiros em 1º de julho de 2013. [acessado 2014 set 01]. Disponível em: http://www.ibge.gov.br/home/estatistica/populacao/estimativa2013/estimativa_dou.shtm
http://www.ibge.gov.br/home/estatistica/...
. With an urbanization rate of approximately 90%, the municipality had 224 health establishments in 2009. Its Human Development Index (HDI) is 0.77, considered to be high in relation to the country. The industry and commerce of the municipality are important economic activities for the region1616. Montes Claros. In: Wikipédia, a enciclopédia livre. Flórida: Wikimedia Foundation; 2014. [acessado 2014 set 12]. Disponível em: http://pt.wikipedia.org/w/index.php?title=Montes_Claros&oldid=39871949
http://pt.wikipedia.org/w/index.php?titl...
.

Sampling: With the aim of obtaining good representation of the adults in the municipality, a complex, probabilistic sampling by clusters and with guarantee of proportionality of gender (54% female, as estimated for the population of the municipality by the IBGE1717. Instituto Brasileiro de Geografia e Estatística (IBGE). Manual do recenseador - CD 1.09. Rio de Janeiro: IBGE; 2000.) was proposed. The calculations showed the need to evaluate 762 adults, assuming a prevalence of events or illnesses at 50%, absolute error of 5.5%, confidence level of 95%, deff equal to 2.0, and non-reply rate of 20%. A prevalence of 50% was adopted to ensure power of inference for a larger number of outcomes, due to the multiplicity of outcomes as investigated in the umbrella project that gave rise to the present study. For the data collection, which was carried out in households, in the urban area, a probabilistic cluster sample was adopted in two stages, the first being the urban census sectors (Primary Sampling Unit – PSUs) and the second comprising the city blocks (Secondary Sampling Units – SSUs). In the rural areas, a choice was made in favor of a probabilistic cluster sample in a single stage, in which the PSUs comprised the rural areas. The PSUs were chosen by simple random selection. Of the 276 urban census sectors, 52 were chosen by lots, and from the 11 rural areas, two were chosen, as per the map of the municipality with the sectors as defined by the IBGE1717. Instituto Brasileiro de Geografia e Estatística (IBGE). Manual do recenseador - CD 1.09. Rio de Janeiro: IBGE; 2000.. In the second stage between 1 and 11 city blocks were chosen by lot in each one of the 52 sectors, totaling 354. Non-residential city blocks (those constituted by squares, churches, industrial companies, barracks or prisons) were excluded. In the rural areas, all the households within a distance of up to 500 meters from an institution of reference were selected. All the households situated in the area selected were sequentially visited, and the adults (aged 35-44) were invited to participate. The option to confer proportionality by gender in the sample (maintaining the same proportion as estimated for the population of the municipality) sought to avoid over-estimation of the feminine gender, as had occurred in other household surveys1818. Brasil. Ministério da Saúde (MS). Secretaria de Atenção à Saúde. Secretaria de Vigilância em Saúde. Departamento de Atenção Básica. Coordenação Geral de Saúde Bucal. Projeto SBBrasil 2010: resultados principais. Brasília: MS; 2011.. More details on the sampling adopted can be found in a prior publication1919. Martins AMEBL, Santos-Neto PE, Batista LHS, Nascimento JE, Gusmão AF, Eleutério NB, Guimarães ALS, Paula AMB, Haikal DS, Silveira MF, Pordeus IA. Plano amostral e ponderação pelo efeito de desenho de um levantamento epidemiológico de saúde bucal. RUC 2012; 14(1):15-29..

Data collection: The interviews were carried out in the households where adults in the chosen age bracket were found. These were duly informed about the survey and invited to participate. All those included in the study signed an informed consent form. Those households where, although they were in the street blocks chosen by lots, no residents were found after three attempts at contact on different days and shifts, were excluded. The interviews were carried out by trained interviewers and the data collected on palm top devices, using a software developed specifically for this survey, enabling simultaneous construction of the data bank.

Variables of the study: HRQOL was evaluated by the SF-1255. Ware JE, Kosinski M, Keller SD. A 12-item short-form health survey: construction of scales and preliminary tests of reliability and validity. Med Care 1996; 34(3):220-233. in its version validated in Brazil by Camelier44. Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004.. This is a more concise version of its predecessor, the SF-3655. Ware JE, Kosinski M, Keller SD. A 12-item short-form health survey: construction of scales and preliminary tests of reliability and validity. Med Care 1996; 34(3):220-233., easier and faster to apply, and sensitive to evaluation of different levels of HRQOL, reliable, and with satisfactory internal consistency66. Silveira MF, Almeida JC, Freire RS, Haikal DS, Martins AEBL. Propriedades psicométricas do instrumento de avaliação da qualidade de vida: 12-item health survey (SF-12). Cien Saude Colet 2013; 18(7):1923-1931.. The instrument comprises 12 items that assess the dimensions: functional capacity, physical aspects, pain, general state of health, vitality, social aspects, emotional aspects and mental health, considering the perception of the individual in relation to the aspects of his/her life in the most recent four weeks. Each one of the 12 items has a group of possible answers distributed on a Likert-type scale, with the possibility, using an algorithm specific to the questionnaire, of calculating its two components: The Physical Component Summary (Physical Component Summary or PCS) and the mental component (Mental Component Summary or MCS). These scores are transformed into a scale of zero to 100, the higher values being correlated to better HRQOL2020. Kosinski M, Ware JE, Turker-Bowker DM, Gandek B. User’s manual for the SF-12v2 health survey: with a supplement documenting the SF-12 health survey. Massachusetts: QualityMetric Incorporated Lincoln, Rhode Island and Health Assessment Lab Boston; 2007.. The scores obtained for each one of the domains were considered as the dependent variables of this study.

The independent variables were grouped into three groups: Social-demographic characteristics, characteristics in relation to health, and behavioral characteristics.

Social-demographic characteristics: Gender, age, marital status, self-declared skin color, level of schooling, income, present work, residency and whether the family owns a car. The variable gender was maintained as collected. The variables age, number of years’ schooling, income and ownership of a car, although collected in a discrete quantitative form, were grouped into categories.

Characteristics relating to health: Use of dental services in the last year, chronic disease, and daily use of medication, maintained as collected.

Behavioral characteristics: Use of tobacco (current smoking habit), consumption of alcoholic beverages (frequency of consumption of alcoholic drink) and practice of physical activity (frequency of physical activity). The variable relating to smoking was presented as collected. The other variables, although collected using a Likert scale, were regrouped into new categories.

Analyses conducted: The statistical software Predictive Analytics Software (PASW/SPSS)® version 18.0 for Windows®, was used. All the estimates were conducted obeying the need for correction for the effect of design, due to their being sourced from cluster samples. In this case, differ ent weightings were attributed to the sample elements to compensate the various probabilities of inclusion, also taking into account the effect of the cluster and the non-response rates.

Initially, descriptive analyses were conducted of all the variables involved. Simple frequencies and corrected percentages were presented. Measures of central tendency (average) and variability (standard error), also corrected, were estimated for the description of the PHC and MHC assessed by the SF-12. Also, a lower limit of CI-95%2121. Utha. Office of Public Health Assessment. Health status in Utah: the medical outcomes study SF-12 (2001 Utah health status survey report). Salt Lake City: Utah Department of Health; 2004. of the estimated average was adopted as cutoff point for PHC and MHC: individuals obtaining scores below the cutoff point, for each of the domains separately, were considered as negative perception of QOL for the domain in question. To estimate the general prevalence of negative perception of HRQOL, the individuals who presented adverse scores on the PHC or the MHC were used.

The association of the PHC and MHC (dependent variables), with the characteristics investigated, were verified using the Student’s t-test and Anova Variance Analysis. The variables that presented a descriptive level (p-value) of 0.20 or less in the bivariate analyses were selected for the multivariable analysis. For this, the General Linear Model (GLM) was used, in which the PHC and the MHC were considered as dependent variables and the selected characteristics as independent variables. The final models were adjusted, maintaining only the variables associated with each domain (descriptive level 0.05 or lower).

Ethical implications: All the participants signed the informed consent form, as set out in Chapter IV of CNS Resolution 196/96. The collection of data qualifies in the Minimum Risk mode of surveys (CNS Resolution 196/96), and the data were obtained after approval of the protocol of the survey by the Institutional Research Ethics Committee.

Results

Of the 924 adults invited to take part in the survey because they lived in the clusters selected by lot, 841 accepted, representing a response rate of 91%. The average age was 39.5. A small predominance of the feminine gender was found. The majority said they were married or had a stable union, stated themselves to be of indigenous blood or negro or mixed-race, did not have an automobile, but had their own home. Level of schooling and per capita income were relatively low: 75% reported having up to 11 years’ schooling and 70% per capita income up to R$ 300.00. Just over a quarter reported not having any formal employment. In the characteristics related to health and behavior, the majority stated they had not used dental services in the last year, did not have a chronic disease, did not take medications daily, did not use tobacco nor alcoholic beverages and never or rarely practiced physical activities (Table 1).

Table 1
Distribution of responses in adults (n = 841), Montes Claros, Minas Gerais, Brazil, with bivariate analysis of the Physical Health Component (PHC) and Mental Health Component (MHC) of the SF-12, by social-demographic characteristics and characteristics relating to health and behavior.

The average values, standard error and CI-95% obtained for the PHC and for the MHC were, respectively, 49.9 (SE 0.50; CI-95% 48.9-50.9) and 47.1 (SE 0.26; CI-95% 46.6-47.7). According to the cutoff points adopted (48.9 for PHC and 46.6 for MHC), 31% and 37.2% of the adults presented negative perception of HRQOL in relation to PHC and MHC, respectively. Of the total of the adults surveyed, 57% thus presented negative perception of HRQOL in at least one domain.

Table 1 compares the averages of PHC and MHC by social-demographic characteristics, and characteristics related to health, and behavior (by variate analysis). At the level of 0.20, the following variables presented associations with both domains of the HRQOL and were included in the multivariable analysis: currently in work, chronic disease, daily use of medication, use of tobacco and practice of physical activity. PHC was further associated with gender, age, level of schooling, income, family ownership of a car, use of dental services and consumption of alcoholic beverages, and there was also observed to be an association between MHC and marital status.

In the multivariable analysis (Table 2) the factors associated with higher PHC scores were: Being male (β = 1.94), family possession of a car (β = 0.89), having used dental services in the last year (β = 1.86), not having a chronic disease (β = 4.60), not using any medication daily (β = 2.09), not using tobacco (β = 2.04) and practicing physical activity (β = 1.73).

Table 2
Multivariable analysis of the Physical Health Component (PHC) of SF-12, by social-demographic characteristics, and characteristics relating to health and behavior – adults of Montes Claros, Minas Gerais State, Brazil; with estimated coefficients (β) by the General Linear Model (GLM) with their respective standard errors (SE).

The variables associated with higher HRQOL scores in relation to MHC were: Not using medication daily (β = 1.91), and not using tobacco (β = 1.26) (Table 3). In a complementary way, Table 4 shows the distribution of adults investigated according to each question from the SF-12.

Table 3
Multivariable analysis of the Mental Health Component (MHC) of SF-12 by social-demographic characteristics, and characteristics relating to health and behavior – adults of Montes Claros, Minas Gerais State, Brazil; with estimated coefficients (β) by the General Linear Model (GLM) with their respective standard errors (SE).
Table 4
Distribution (n and %) of responses by adults of Montes Claros, Brazil, in each question of the SF-12.

Discussion

This survey showed a high percentage of low HRQOL among adults, since more than half of the subjects investigated (57%) presented negative perception of HRQOL either in PHC or in MHC. Considering that this is a sample of adults in general of the community, not selected by reason of presenting any specific pathology, the result is a matter of concern. MHC had a higher occurrence of adverse values, and a lower average score, than PHC. Daily use of medication, and the habit of smoking, were associated with lower levels of HRQOL, both in PHC and in MHC. PHC was further associated with gender, family ownership of a car, use of dental services, chronic disease and practice of physical activity.

Average values obtained for PHC (49.9) and MHC (47.1) were similar to those found in a population-based study in the city of São Paulo, comparing 108 people suffering from Chronic Obstructive Pulmonary Disease – CPOD (PHC = 49.7; MHC = 50.4) and 670 controls (PHC = 51.9; MHC = 51.5), in which the average age of the sample investigated was 5444. Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004.. Considering that this present survey was conducted on adults in general, not suffering from any specific disease, and that the average age was 39.5, a greater HRQOL would be expected for the adults of Montes Claros than for people suffering from COPD, but this was not the case. At the same time, the average found for the PHC among adults of Montes Claros was higher than that found in people with prostate cancer (43.5)77. Song L, Mishel M, Bensen JT, Chen RC, Knafl GJ, Blackard B, Farnan L, Fontham E, Joseph Su L, Brennan CS, Mohler JL, Godley PA. How does health literacy affect quality of life among men with newly diagnosed clinically localized prostate cancer? Findings from the North Carolina-Louisiana Prostate Cancer Project (PCaP). Cancer 2012; 118(15):3842-3851., individuals in hemodialysis (39.7)1212. Lopes GB, Martins MTS, Matos CM, Amorim JL, Leite EB, Miranda EA, Lopes AA. Comparações de medidas de qualidade de vida entre mulheres e homens em hemodiálise. Rev Assoc Med Bras 2007; 53(6):506-509., and patients with advanced stages of cancer (37.1)88. Rouanne M, Massard C, Hollebecque A, Rousseau V, Varga A, Gazzah A, Neuzillet Y, Lebret T, Soria JC. Evaluation of sexuality, health-related quality-of-life and depression in advanced cancer patients: a prospective study in a Phase I clinical trial unit of predominantly targeted anticancer drugs. Eur J Cancer 2013; 49(2):431-438., although it was lower than that found for individuals with generalized chronic pain (53.8)1111. Nicholl BI, Macfarlane GJ, Davies KA, Morriss R, Dickens C, McBeth J. Premorbid psychosocial factors are associated with poor health-related quality of life in subjects with new onset of chronic widespread pain – Results from the EPIFUND study. Pain 2009; 141(1-2):119-126.. As for MHC, the average found for adults of Montes Claros was lower than that found for people with prostate cancer (52.1)77. Song L, Mishel M, Bensen JT, Chen RC, Knafl GJ, Blackard B, Farnan L, Fontham E, Joseph Su L, Brennan CS, Mohler JL, Godley PA. How does health literacy affect quality of life among men with newly diagnosed clinically localized prostate cancer? Findings from the North Carolina-Louisiana Prostate Cancer Project (PCaP). Cancer 2012; 118(15):3842-3851. and people with generalized chronic pain (53.0)1111. Nicholl BI, Macfarlane GJ, Davies KA, Morriss R, Dickens C, McBeth J. Premorbid psychosocial factors are associated with poor health-related quality of life in subjects with new onset of chronic widespread pain – Results from the EPIFUND study. Pain 2009; 141(1-2):119-126.; close to the level found for people undergoing hemodialysis (47.7)1212. Lopes GB, Martins MTS, Matos CM, Amorim JL, Leite EB, Miranda EA, Lopes AA. Comparações de medidas de qualidade de vida entre mulheres e homens em hemodiálise. Rev Assoc Med Bras 2007; 53(6):506-509.; – and higher than the levels found for patients with advanced stage cancer (43.8)88. Rouanne M, Massard C, Hollebecque A, Rousseau V, Varga A, Gazzah A, Neuzillet Y, Lebret T, Soria JC. Evaluation of sexuality, health-related quality-of-life and depression in advanced cancer patients: a prospective study in a Phase I clinical trial unit of predominantly targeted anticancer drugs. Eur J Cancer 2013; 49(2):431-438. and among patients with chronic liver diseases (43.01)1010. Svirtlih N, Pavic S, Terzic D, Delic D, Simonovic J, Gvozdenovic E, Boricic I. Reduced quality of life in patients with chronic viral liver disease as assessed by SF12 questionnaire. J Gastrointestin Liver Dis 2008; 17(4):405-409.. Identification of higher average scores for PHC than MHC had already been found in previous studies using the SF-121010. Svirtlih N, Pavic S, Terzic D, Delic D, Simonovic J, Gvozdenovic E, Boricic I. Reduced quality of life in patients with chronic viral liver disease as assessed by SF12 questionnaire. J Gastrointestin Liver Dis 2008; 17(4):405-409.,1111. Nicholl BI, Macfarlane GJ, Davies KA, Morriss R, Dickens C, McBeth J. Premorbid psychosocial factors are associated with poor health-related quality of life in subjects with new onset of chronic widespread pain – Results from the EPIFUND study. Pain 2009; 141(1-2):119-126.,2222. Silveira MF, Almeida JC, Freire RS, Ferreira RC, Martins AEBL, Marcopito LF. Qualidade de vida entre adolescentes: estudo seccional empregando o SF-12. Cien Saude Colet 2013; 18(7):2007-2015..

Further, it is worth highlighting that to estimate the occurrence of negative perception of HRQOL, the lower limits of the CI-95% of the sample average obtained2121. Utha. Office of Public Health Assessment. Health status in Utah: the medical outcomes study SF-12 (2001 Utah health status survey report). Salt Lake City: Utah Department of Health; 2004. (48.9 for PHC and 46.6 for MHC) were adopted as cutoff points for PHC and MHC. Some studies have adopted cutoff points of 50 for PHC and 42 for MHC55. Ware JE, Kosinski M, Keller SD. A 12-item short-form health survey: construction of scales and preliminary tests of reliability and validity. Med Care 1996; 34(3):220-233.,2222. Silveira MF, Almeida JC, Freire RS, Ferreira RC, Martins AEBL, Marcopito LF. Qualidade de vida entre adolescentes: estudo seccional empregando o SF-12. Cien Saude Colet 2013; 18(7):2007-2015.. However, the adoption of an arbitrary and single cutoff point for all the studies may possibly not be the best way of identifying individuals with adversely affected QOL, since their levels vary in different populations, with different age groups and different contexts. Thus, adoption of specific cutoff points for each study carried out was suggested, and adoption of the lower limit of the CI-95% appears to be appropriate for differentiating individuals with lower QOL taking into account the specific average levels of the population under study2121. Utha. Office of Public Health Assessment. Health status in Utah: the medical outcomes study SF-12 (2001 Utah health status survey report). Salt Lake City: Utah Department of Health; 2004..

Prior studies found the influence of some of the social-demographic characteristics, and characteristics related to health and behavior, on HRQOL44. Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004.,2222. Silveira MF, Almeida JC, Freire RS, Ferreira RC, Martins AEBL, Marcopito LF. Qualidade de vida entre adolescentes: estudo seccional empregando o SF-12. Cien Saude Colet 2013; 18(7):2007-2015.

23. Lee HA, Lee KE, Jeong YW, Ryu J, Kim M, Min JW, Hong YS, Jung-Choi K, Park H. How do life-course trajectories of socioeconomic position affect quality of life in patients with diabetes mellitus? Qual Life Res 2014; 23(4):1337-1344.

24. Gordia AP, Quadros TMB, Campos W. Variáveis sociodemográficas como determinantes do domínio meio ambiente da qualidade de vida de adolescentes. Cien Saude Colet 2009; 14(6):2261-2268.

25. Sprangers MAG, Regt EB, Andries F, Van Agt HME, Bijl RV, De Boer JB, Foets M, Hoeymans N, Jacobs AE, Kempen GIJM, Miedema HS, Tijhuis MAR, De Haes HCJM. Which chronic conditions are associated with better or poorer quality of life? J Clin Epidemiol 2000; 53(9):895-907.
-2626. Cruz LN, Fleck MPA, Oliveira MR, Camey SA, Hoffmann JF, Bagattini AM, Polanczyk CA. Health-related quality of life in Brazil: normative data for the SF-36 in a general population sample in the south of the country. Cien Saude Colet 2013; 18(7):1911-1921.. Higher levels of HRQOL in the PHC for male individuals had already been found in Brazilian literature1212. Lopes GB, Martins MTS, Matos CM, Amorim JL, Leite EB, Miranda EA, Lopes AA. Comparações de medidas de qualidade de vida entre mulheres e homens em hemodiálise. Rev Assoc Med Bras 2007; 53(6):506-509.,2626. Cruz LN, Fleck MPA, Oliveira MR, Camey SA, Hoffmann JF, Bagattini AM, Polanczyk CA. Health-related quality of life in Brazil: normative data for the SF-36 in a general population sample in the south of the country. Cien Saude Colet 2013; 18(7):1911-1921.,2727. Lima MG, Barros MBA, César CLG, Goldbaum M, Carandina L, Ciconelli RM. Health related quality of life among the elderly: a population-based study using SF-36 survey. Cad Saude Publica 2009; 25(10):2159-2167. and international literature1111. Nicholl BI, Macfarlane GJ, Davies KA, Morriss R, Dickens C, McBeth J. Premorbid psychosocial factors are associated with poor health-related quality of life in subjects with new onset of chronic widespread pain – Results from the EPIFUND study. Pain 2009; 141(1-2):119-126.,2525. Sprangers MAG, Regt EB, Andries F, Van Agt HME, Bijl RV, De Boer JB, Foets M, Hoeymans N, Jacobs AE, Kempen GIJM, Miedema HS, Tijhuis MAR, De Haes HCJM. Which chronic conditions are associated with better or poorer quality of life? J Clin Epidemiol 2000; 53(9):895-907.,2828. Ribeiro JLP. O importante é a saúde: estudo de adaptação de uma técnica de avaliação do estado de saúde - SF-36. Lisboa: Fundação Merck Sherp & Dohme; 2005.. A prior study showed that women were more concerned with their state of health and seek more medical care than men2929. Saeed AA, Al-Hamdan NA, Bahnassy AA, Abdalla AM, Abbas MA, Abuzaid LZ. Prevalence, awareness, treatment, and control of hypertension among Saudi adult population: a national survey. Int J Hypertens 2011; 2011:174135. and, thus, may present a greater proportion of adversely-affected HRQOL2626. Cruz LN, Fleck MPA, Oliveira MR, Camey SA, Hoffmann JF, Bagattini AM, Polanczyk CA. Health-related quality of life in Brazil: normative data for the SF-36 in a general population sample in the south of the country. Cien Saude Colet 2013; 18(7):1911-1921. than men.

It was interesting to observe that although ownership of a car did not apparently have a direct relationship with HRQOL, it was shown to be associated with PHC, increasing HRQOL in the PHC by 0.89 units in relation to people whose family did not have a car. Where families do not own cars, and are possibly dependent on public transport for daily travel, the problems of transport infrastructure and the quality of transport used could adversely affect peoples’ mobility and their capacity to carry out routine travel. A study in São Paulo observed that mobility was directly related to citizens’ QOL, and brought with it the possibility of people participating in the activities that they wanted to participate in3030. Cardoso CEP. Análise do transporte coletivo urbano sob a ótica dos riscos e carências sociais [tese]. São Paulo: Pontifícia Universidade Católica de São Paulo; 2008..

Use of dental service in the last year was found to be associated with higher levels of HRQOL in the PHC. A prior study showed that the effects of oral disorders were associated with a negative perception of HRQOL, in the PHC and MHC of the SF-123131. Martins AMEBL, Jones KM, Souza JGS, Pordeus IA. Associação entre impactos funcionais e psicossociais das desordens bucais e qualidade de vida entre idosos. Cien Saude Colet 2014; 19(8):3461-3478.. Oral diseases can adversely affect HRQOL and operate restrictions on individuals’ daily activities. The recent use of dental services can minimize such effects and give the sensation of “being up-to-date with oral health”.

At the same time, absence of chronic diseases had a pronounced effect of increasing (by 4.6 units) the levels of HRQOL in the PHC. It is not surprising that this variable was the one that made the largest contribution in the multiple model of the PHC, since the SF-12 focuses on well-being related to conditions of health. A prior study held on a sample of 755 individuals of the general population of Porto Alegre, aged 20 to 64, using the SF-36, also showed less good HRQOL for those who had self-related chronic disease2626. Cruz LN, Fleck MPA, Oliveira MR, Camey SA, Hoffmann JF, Bagattini AM, Polanczyk CA. Health-related quality of life in Brazil: normative data for the SF-36 in a general population sample in the south of the country. Cien Saude Colet 2013; 18(7):1911-1921.. Also, studies of those suffering from some chronic disease also showed a significant increase in levels of HRQOL for the control subjects having no disease44. Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004.,1010. Svirtlih N, Pavic S, Terzic D, Delic D, Simonovic J, Gvozdenovic E, Boricic I. Reduced quality of life in patients with chronic viral liver disease as assessed by SF12 questionnaire. J Gastrointestin Liver Dis 2008; 17(4):405-409.. It has also been observed that the presence of co-morbidities significantly reduces HRQOL77. Song L, Mishel M, Bensen JT, Chen RC, Knafl GJ, Blackard B, Farnan L, Fontham E, Joseph Su L, Brennan CS, Mohler JL, Godley PA. How does health literacy affect quality of life among men with newly diagnosed clinically localized prostate cancer? Findings from the North Carolina-Louisiana Prostate Cancer Project (PCaP). Cancer 2012; 118(15):3842-3851.,2525. Sprangers MAG, Regt EB, Andries F, Van Agt HME, Bijl RV, De Boer JB, Foets M, Hoeymans N, Jacobs AE, Kempen GIJM, Miedema HS, Tijhuis MAR, De Haes HCJM. Which chronic conditions are associated with better or poorer quality of life? J Clin Epidemiol 2000; 53(9):895-907.,2828. Ribeiro JLP. O importante é a saúde: estudo de adaptação de uma técnica de avaliação do estado de saúde - SF-36. Lisboa: Fundação Merck Sherp & Dohme; 2005.,3232. Campolina AG, Dini PS, Ciconelli RM. Impacto da doença crônica na qualidade de vida de idosos da comunidade em São Paulo (SP, Brasil). Cien Saude Colet 2011; 16(6):2919-2925.. No association was found in this present investigation between reporting of chronic disease and MHC – which was a surprise. Perhaps, because of the characteristics of the population researched, relatively young adults, that were not suffering from specific diseases, most of them functionally independent and in work, the fact of reporting a chronic disease was not a sufficient factor to motivate an effect on the MHC of HRQOL.

The need for daily use of medication, on the other hand, was shown to be associated with HRQOL both in its PHC and MHC. The need for daily use of medication is, probably, due to the presence of chronic conditions, which is strongly associated with worse levels of HRQOL, as has been extremely widely shown in the literature44. Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004.,1010. Svirtlih N, Pavic S, Terzic D, Delic D, Simonovic J, Gvozdenovic E, Boricic I. Reduced quality of life in patients with chronic viral liver disease as assessed by SF12 questionnaire. J Gastrointestin Liver Dis 2008; 17(4):405-409.,1111. Nicholl BI, Macfarlane GJ, Davies KA, Morriss R, Dickens C, McBeth J. Premorbid psychosocial factors are associated with poor health-related quality of life in subjects with new onset of chronic widespread pain – Results from the EPIFUND study. Pain 2009; 141(1-2):119-126.,2626. Cruz LN, Fleck MPA, Oliveira MR, Camey SA, Hoffmann JF, Bagattini AM, Polanczyk CA. Health-related quality of life in Brazil: normative data for the SF-36 in a general population sample in the south of the country. Cien Saude Colet 2013; 18(7):1911-1921.,3333. Bergh KAM, Essink-Bot M L, Borsboom GJJM, Scholten ET, Prokop M, Koning HJ, Klaveren RJ. Short-term health-related quality of life consequences in a lungcancer CT screening trial (NELSON). Br J Cancer 2010; 102(1):27-34.,3434. Andrade TL, Camelier AA, Rosa FW, Santos MP, Jezler S, Silva JLP. Aplicabilidade do questionário de qualidade de vida relacionada à saúde - the 12-Item Short-Form Health Survey - em pacientes portadores de esclerose sistêmica progressiva. J Bras Pneumol 2007; 33(4):414-422.. Daily use of medication possibly carries with it the idea of a more serious disease, dependence and obligation, acting as a factor for anxiety and/or depression. A prior study showed that anxious or depressive individuals had, respectively, four and five times the risk of having lower MHC scores1111. Nicholl BI, Macfarlane GJ, Davies KA, Morriss R, Dickens C, McBeth J. Premorbid psychosocial factors are associated with poor health-related quality of life in subjects with new onset of chronic widespread pain – Results from the EPIFUND study. Pain 2009; 141(1-2):119-126..

Adults that did not report a smoking habit presented a higher HRQOL both in the PHC and MHC, than those that smoke. A study with 60 patients who took part in a program to give up smoking, to evaluate HRQOL using the SF-36, found ex-smokers to have a significant improvement in PHC and MHC after the program of one year of abstinence3535. Sales MPU, Oliveira MI, Mattos IM, Viana CMS, Pereira EDB. Impacto da cessação tabágica na qualidade de vida dos pacientes. J Bras Pneumol 2009; 35(5):436-441.. In the present survey it was found that non-use of tobacco increased HRQOL by 2.04 units in the PHC and 1.26 units in the MHC, and this is compatible with the previous studies3636. Mulder I, Tijhuis M, Smit HA, Kromhout D. Smoking cessation and quality of life: the effect of amount of smoking and time since quitting. Prev Med 2001; 33(6):653-660.,3737. Zillich AJ, Ryan M, Adams A, Yeager B, Farris K. Effectiveness of a pharmacist-based smoking-cessation program and its impact on quality of life. Pharmacotherapy 2002; 22(6):759-765. which found that active smokers report a worse general state of health than non-smokers or ex-smokers. Once again, the question of daily dependency seems to be associated with the MHC of HRQOL. The smoker, as well as suffering from the dependency itself, suffers strong pressure from society, which often blames these individuals – rather than supporting them in a change to healthier behavior, in line with the principle of ‘promotion of health’ – giving rise to forms of social exclusion, prejudice, feelings of blame and fear, leaving them at the mercy of themselves and their addiction3838. Czeresnia D, Freitas CM, organizadores. Promoção da saúde: conceito, reflexões, tendências. Rio de Janeiro: Fiocruz; 2003.. This shows the importance of programs for support in giving up the smoking habit for greater wellbeing and health of the population, based on ‘health literacy’, a relatively new concept in Health Promotion, used to describe the results of the activities of education and communication, focusing on giving people better access to health information and on individuals’ capacity to use such information efficiently, providing the basis for empowerment3939. Nutbeam D. Health literacy as a public health goal: a challenge for contemporary health education and communication strategies into the 21st century. Health Promot Int 2000; 15(3):259-267..

The practice of physical activity, found in only 20% of the adults interviewed, was shown to be associated with better levels of HRQOL in the PHC. Other studies have already shown that regular practice of physical activity and greater physical aptitude are associated with lower rates of mortality and better HRQOL in populations of adults4040. Gillison FB, Skevington SM, Sato A, Standage M, Evangelidou S. The effects of exercise interventions on quality of life in clinical and healthy populations; a meta-analysis. Soc Sci Med 2009; 68(9):1700-1710. and adolescents2222. Silveira MF, Almeida JC, Freire RS, Ferreira RC, Martins AEBL, Marcopito LF. Qualidade de vida entre adolescentes: estudo seccional empregando o SF-12. Cien Saude Colet 2013; 18(7):2007-2015.. There are increasing numbers of data showing that exercise, and physical aptitude and activity are related to prevention and rehabilitation of diseases and QOL and wellbeing4040. Gillison FB, Skevington SM, Sato A, Standage M, Evangelidou S. The effects of exercise interventions on quality of life in clinical and healthy populations; a meta-analysis. Soc Sci Med 2009; 68(9):1700-1710.,4141. Sarwer DB, Moore RH, Diewald LK, Chittams J, Berkowitz RI, Vetter M, Volger S, Wadden TA; POWER-UP Research Group. The impact of a primary care-based weight loss intervention on quality of life. Int J Obes (Lond) 2013; 37(Supl. 1):25-30., and that these behaviors should be stimulated and that public policies should ensure that there are appropriate situations and environments for such practices.

This study made a multiple regression through the general linear model, which is indicated for numerical dependent variables and offers the advantage of observing the magnitude of the impact on the dependent variable with alteration of one unit in the independent variable, which makes the analysis more sensitive. Generalized linear models were formulated as a way of unifying various statistical models, including linear, logistical and Poisson regression, under a single theoretical framework, making it possible to develop a general algorithm for the estimate of maximum verisimilitude in all these models4242. Nelder JA, Wedderburn RWM. Generalized Linear Models. J R Statist Soc 1972; A135(3):370-384.. A prior investigation, investigation, of adolescents2222. Silveira MF, Almeida JC, Freire RS, Ferreira RC, Martins AEBL, Marcopito LF. Qualidade de vida entre adolescentes: estudo seccional empregando o SF-12. Cien Saude Colet 2013; 18(7):2007-2015., had adopted a general linear model in the analysis of data coming from the SF-12.

A limitation of this work relates to the fact that it is a cross-sectional study, which does not allow a temporal relationship to be established between QOL and the independent variables researched. As for the percentage of variance explained by the final models, it is found that this was modest (adjusted R2 of 18% for PHC and 3% for MHC), largely because QOL represents a complex and multifactorial outcome, and it is probable that important explanatory variables have not been included in the analyses, indicating that only a partial comprehension can be achieved through epidemiological studies of this type. Unfortunately, most of the studies do not present the percentage of the variance that could be explained by the models obtained, making comparisons in this respect difficult.

The absolute error adopted in the calculation of the sample size was 5.5%, resulting in n = 762 individuals. If an absolute error of 5% were adopted in the sampling planning, keeping the other parameters fixed, the final sample calculated would be 819 individuals, lower than the one obtained in reality (n = 841). That is to say, the final sample ensured power of inference considering an absolute error of 5%. It should be further commented that this study is a sub-section of a larger project. The sampling calculation of the larger project was made for an estimate of a prevalence (50%, so as to ensure a larger sample and, consequently, a higher power of inference for the various outcomes investigated). However, the objective of the present investigation was not to estimate a prevalence, but averages, and the linear model was adopted to identify the factors that could contribute to higher average levels of QOL, both in its PHC and its MHC. Thus, if the calculation of the sample size were revised to attend specifically to the objectives of this present investigation, we would have an even lower error than the one indicated (5%). A simulation adopting the formula n = 50 + 8K (where k = the number of independent variables of the linear model)4343. Green SB. How many subjects does it take to do a regression analysis? Multivariate Behavioural Research 1991; 26(3):499-510. showed that the size of the sample was well above the necessary size, ensuring a lower error and, consequently, a higher power of inference for the outcome investigated.

Further investigations are necessary to achieve increasingly good understanding about adult HRQOL and well-being, concomitantly including physical, social, cultural, and behavioral variables, such as health literacy, social capital, occurrence of psychic disorders, access to the health services, work satisfaction, composition of the family, religiosity and spirituality, all of which have so far been little studied in relation to QOL.

Conclusion

The high prevalence (57%) of adverse effect on HRQOL among adults of the community in general is a concern. It was found that being male, having a car in the family, having recently used dental services, not having a chronic disease, not using medication daily, not being a smoker, and practicing physical activities were related to higher levels in the PHC of the HRQOL. Also, not using daily medication, and not being a smoker, were associated with higher levels in the MHC of the HRQOL. The adult population, because of its social and economic importance, deserves greater attention from studies and an increase in policies designed to maintain and/or recover its physical and mental well-being.

Acknowledgments

Os autores agradecem o apoio logístico da Unimontes e da Prefeitura Municipal de Montes Claros, o fomento da Fundação de Amparo a Pesquisa Estado de Minas Gerais (FAPEMIG) e a colaboração de todos os participantes que aceitaram participar desse estudo. DD Noronha é bolsista de mestrado pela Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). AMEBL Martins é bolsista de Pós-Doc pelo Conselho Nacional de Desenvolvimento Cientifico e Tecnológico (CNPq). AMB De-Paula é bolsista de Pós-Doc pela Capes (Science Without Borders Program) e pesquisador do CNPq.

References

  • 1
    The WHOQOL Group. The World Health Organization quality of life assessment (WHOQOL): position paper from the World Health Organization. Soc Sci Med 1995; 41(10):1403-1409.
  • 2
    Ferrans CE. Development of a conceptual model of quality of life. Sch Inq Nurs Pract 1996; 10(3):293-304.
  • 3
    Guyatt GH, Feeny DH, Patrick DL. Measuring health-related quality of life. Ann Intern Med 1993; 118(8):622-629.
  • 4
    Camelier AA. Avaliação da Qualidade de Vida Relacionada à Saúde em Pacientes com DPOC: estudo de base populacional com o SF-12 na cidade de São Paulo-SP [tese]. São Paulo: Universidade Federal de São Paulo; 2004.
  • 5
    Ware JE, Kosinski M, Keller SD. A 12-item short-form health survey: construction of scales and preliminary tests of reliability and validity. Med Care 1996; 34(3):220-233.
  • 6
    Silveira MF, Almeida JC, Freire RS, Haikal DS, Martins AEBL. Propriedades psicométricas do instrumento de avaliação da qualidade de vida: 12-item health survey (SF-12). Cien Saude Colet 2013; 18(7):1923-1931.
  • 7
    Song L, Mishel M, Bensen JT, Chen RC, Knafl GJ, Blackard B, Farnan L, Fontham E, Joseph Su L, Brennan CS, Mohler JL, Godley PA. How does health literacy affect quality of life among men with newly diagnosed clinically localized prostate cancer? Findings from the North Carolina-Louisiana Prostate Cancer Project (PCaP). Cancer 2012; 118(15):3842-3851.
  • 8
    Rouanne M, Massard C, Hollebecque A, Rousseau V, Varga A, Gazzah A, Neuzillet Y, Lebret T, Soria JC. Evaluation of sexuality, health-related quality-of-life and depression in advanced cancer patients: a prospective study in a Phase I clinical trial unit of predominantly targeted anticancer drugs. Eur J Cancer 2013; 49(2):431-438.
  • 9
    Menezes ASOP, Len CA, Hilário MOE, Terreri MTRA, Braga JAP. Qualidade de vida em portadores de doença falciforme. Rev paul pediatr 2013; 31(1):24-29.
  • 10
    Svirtlih N, Pavic S, Terzic D, Delic D, Simonovic J, Gvozdenovic E, Boricic I. Reduced quality of life in patients with chronic viral liver disease as assessed by SF12 questionnaire. J Gastrointestin Liver Dis 2008; 17(4):405-409.
  • 11
    Nicholl BI, Macfarlane GJ, Davies KA, Morriss R, Dickens C, McBeth J. Premorbid psychosocial factors are associated with poor health-related quality of life in subjects with new onset of chronic widespread pain – Results from the EPIFUND study. Pain 2009; 141(1-2):119-126.
  • 12
    Lopes GB, Martins MTS, Matos CM, Amorim JL, Leite EB, Miranda EA, Lopes AA. Comparações de medidas de qualidade de vida entre mulheres e homens em hemodiálise. Rev Assoc Med Bras 2007; 53(6):506-509.
  • 13
    Pinto VG. Saúde bucal coletiva. 4ª Edição. São Paulo: Editora Santos; 2000.
  • 14
    Reisine ST, Bailit HL. Clinical oral health status and adult perceptions of oral health. Soc Sci Med Med Psychol Med Sociol 1980; 14A(6):597-605.
  • 15
    Instituto Brasileiro de Geografia e Estatística (IBGE). Estimativas populacionais para os municípios brasileiros em 1º de julho de 2013 [acessado 2014 set 01]. Disponível em: http://www.ibge.gov.br/home/estatistica/populacao/estimativa2013/estimativa_dou.shtm
    » http://www.ibge.gov.br/home/estatistica/populacao/estimativa2013/estimativa_dou.shtm
  • 16
    Montes Claros. In: Wikipédia, a enciclopédia livre. Flórida: Wikimedia Foundation; 2014. [acessado 2014 set 12]. Disponível em: http://pt.wikipedia.org/w/index.php?title=Montes_Claros&oldid=39871949
    » http://pt.wikipedia.org/w/index.php?title=Montes_Claros&oldid=39871949
  • 17
    Instituto Brasileiro de Geografia e Estatística (IBGE). Manual do recenseador - CD 1.09. Rio de Janeiro: IBGE; 2000.
  • 18
    Brasil. Ministério da Saúde (MS). Secretaria de Atenção à Saúde. Secretaria de Vigilância em Saúde. Departamento de Atenção Básica. Coordenação Geral de Saúde Bucal. Projeto SBBrasil 2010: resultados principais Brasília: MS; 2011.
  • 19
    Martins AMEBL, Santos-Neto PE, Batista LHS, Nascimento JE, Gusmão AF, Eleutério NB, Guimarães ALS, Paula AMB, Haikal DS, Silveira MF, Pordeus IA. Plano amostral e ponderação pelo efeito de desenho de um levantamento epidemiológico de saúde bucal. RUC 2012; 14(1):15-29.
  • 20
    Kosinski M, Ware JE, Turker-Bowker DM, Gandek B. User’s manual for the SF-12v2 health survey: with a supplement documenting the SF-12 health survey Massachusetts: QualityMetric Incorporated Lincoln, Rhode Island and Health Assessment Lab Boston; 2007.
  • 21
    Utha. Office of Public Health Assessment. Health status in Utah: the medical outcomes study SF-12 (2001 Utah health status survey report) Salt Lake City: Utah Department of Health; 2004.
  • 22
    Silveira MF, Almeida JC, Freire RS, Ferreira RC, Martins AEBL, Marcopito LF. Qualidade de vida entre adolescentes: estudo seccional empregando o SF-12. Cien Saude Colet 2013; 18(7):2007-2015.
  • 23
    Lee HA, Lee KE, Jeong YW, Ryu J, Kim M, Min JW, Hong YS, Jung-Choi K, Park H. How do life-course trajectories of socioeconomic position affect quality of life in patients with diabetes mellitus? Qual Life Res 2014; 23(4):1337-1344.
  • 24
    Gordia AP, Quadros TMB, Campos W. Variáveis sociodemográficas como determinantes do domínio meio ambiente da qualidade de vida de adolescentes. Cien Saude Colet 2009; 14(6):2261-2268.
  • 25
    Sprangers MAG, Regt EB, Andries F, Van Agt HME, Bijl RV, De Boer JB, Foets M, Hoeymans N, Jacobs AE, Kempen GIJM, Miedema HS, Tijhuis MAR, De Haes HCJM. Which chronic conditions are associated with better or poorer quality of life? J Clin Epidemiol 2000; 53(9):895-907.
  • 26
    Cruz LN, Fleck MPA, Oliveira MR, Camey SA, Hoffmann JF, Bagattini AM, Polanczyk CA. Health-related quality of life in Brazil: normative data for the SF-36 in a general population sample in the south of the country. Cien Saude Colet 2013; 18(7):1911-1921.
  • 27
    Lima MG, Barros MBA, César CLG, Goldbaum M, Carandina L, Ciconelli RM. Health related quality of life among the elderly: a population-based study using SF-36 survey. Cad Saude Publica 2009; 25(10):2159-2167.
  • 28
    Ribeiro JLP. O importante é a saúde: estudo de adaptação de uma técnica de avaliação do estado de saúde - SF-36 Lisboa: Fundação Merck Sherp & Dohme; 2005.
  • 29
    Saeed AA, Al-Hamdan NA, Bahnassy AA, Abdalla AM, Abbas MA, Abuzaid LZ. Prevalence, awareness, treatment, and control of hypertension among Saudi adult population: a national survey. Int J Hypertens 2011; 2011:174135.
  • 30
    Cardoso CEP. Análise do transporte coletivo urbano sob a ótica dos riscos e carências sociais [tese]. São Paulo: Pontifícia Universidade Católica de São Paulo; 2008.
  • 31
    Martins AMEBL, Jones KM, Souza JGS, Pordeus IA. Associação entre impactos funcionais e psicossociais das desordens bucais e qualidade de vida entre idosos. Cien Saude Colet 2014; 19(8):3461-3478.
  • 32
    Campolina AG, Dini PS, Ciconelli RM. Impacto da doença crônica na qualidade de vida de idosos da comunidade em São Paulo (SP, Brasil). Cien Saude Colet 2011; 16(6):2919-2925.
  • 33
    Bergh KAM, Essink-Bot M L, Borsboom GJJM, Scholten ET, Prokop M, Koning HJ, Klaveren RJ. Short-term health-related quality of life consequences in a lungcancer CT screening trial (NELSON). Br J Cancer 2010; 102(1):27-34.
  • 34
    Andrade TL, Camelier AA, Rosa FW, Santos MP, Jezler S, Silva JLP. Aplicabilidade do questionário de qualidade de vida relacionada à saúde - the 12-Item Short-Form Health Survey - em pacientes portadores de esclerose sistêmica progressiva. J Bras Pneumol 2007; 33(4):414-422.
  • 35
    Sales MPU, Oliveira MI, Mattos IM, Viana CMS, Pereira EDB. Impacto da cessação tabágica na qualidade de vida dos pacientes. J Bras Pneumol 2009; 35(5):436-441.
  • 36
    Mulder I, Tijhuis M, Smit HA, Kromhout D. Smoking cessation and quality of life: the effect of amount of smoking and time since quitting. Prev Med 2001; 33(6):653-660.
  • 37
    Zillich AJ, Ryan M, Adams A, Yeager B, Farris K. Effectiveness of a pharmacist-based smoking-cessation program and its impact on quality of life. Pharmacotherapy 2002; 22(6):759-765.
  • 38
    Czeresnia D, Freitas CM, organizadores. Promoção da saúde: conceito, reflexões, tendências Rio de Janeiro: Fiocruz; 2003.
  • 39
    Nutbeam D. Health literacy as a public health goal: a challenge for contemporary health education and communication strategies into the 21st century. Health Promot Int 2000; 15(3):259-267.
  • 40
    Gillison FB, Skevington SM, Sato A, Standage M, Evangelidou S. The effects of exercise interventions on quality of life in clinical and healthy populations; a meta-analysis. Soc Sci Med 2009; 68(9):1700-1710.
  • 41
    Sarwer DB, Moore RH, Diewald LK, Chittams J, Berkowitz RI, Vetter M, Volger S, Wadden TA; POWER-UP Research Group. The impact of a primary care-based weight loss intervention on quality of life. Int J Obes (Lond) 2013; 37(Supl. 1):25-30.
  • 42
    Nelder JA, Wedderburn RWM. Generalized Linear Models. J R Statist Soc 1972; A135(3):370-384.
  • 43
    Green SB. How many subjects does it take to do a regression analysis? Multivariate Behavioural Research 1991; 26(3):499-510.

Publication Dates

  • Publication in this collection
    Feb 2016

History

  • Received
    15 Sept 2014
  • Reviewed
    05 May 2015
  • Accepted
    07 May 2015
ABRASCO - Associação Brasileira de Saúde Coletiva Rio de Janeiro - RJ - Brazil
E-mail: revscol@fiocruz.br