ABSTRACT:

This study assessed the prevalence of depression and associated factors among Brazilian elderly in Arroio Trinta, Southern Brazil. During home visits, a questionnaire was administered to all people aged 60 or older living in the municipality in 2013. The Geriatric Depression Scale Short Form (GDS-15) was used. The χ ² test was performed to compare proportions and Poisson regression with robust adjustment of variance in the multivariate analysis. The effect measure applied was the prevalence ratio. The prevalence of depression among 552 (out of 568) elderly studied was 20.4% (95%CI 17.3 - 23.8). An adjusted analysis conducted according to a predefined hierarchical model showed higher prevalence ratios of depression among females, single people, those with lower household income, smokers, and those who had been hospitalized in the 12 months preceding the interview. Engaging in leisure-time activities such as dances and religious activities or regular physical activity were protective factors for depression. Results from this study demonstrate the need of proper treatment and management of this condition at the community level.

Keywords:
Depression; Aged; Prevalence; Health surveys; Risk factors; Observational study

INTRODUCTION

The populational aging has increased the burden of diseases in the population, especially regarding psychiatric disorders, particularly depression¹1. Mann A. Depression in the elderly: findings from a community survey. Maturitas 2001; 38(1): 53-8.. This is especially relevant in Brazil, once that it is estimated that in 2045 the number of elderly will be greater that the number of children in the country²2. Wong LLR, Carvalho JA. O rápido processo de envelhecimento do Brasil: sérios desafios para as políticas públicas. Rev Bras Estud Popul 2006; 23(1): 5-26..

The prevalence of depression in the elderly population in the literature varies from slightly above 2 to 50%, depending on the scale used, the place where the study was conducted, and the age range included³3. Lyness JM, Caine ED, King DA, Cox C, Yoediono Z. Psychiatric disorders in older primary care patients. J Gen Intern Med 1999; 14(4): 249-54.^,44. Veras RP, Coutinho E. Prevalência da síndrome cerebral orgânica em população de idosos de área metropolitana da região sudeste do Brasil. Rev Saúde Pública 1994; 28(1): 26-37.^,55. Silberman C, Souza C, Wilhems F, Kipper L, Wu V, Diogo C, et al. Cognitive deficit and depressive symptoms in a community group of elderly people: a preliminary study. Rev Saúde Pública 1995; 29(6): 444-50.^,66. Blay SL, Bickel H, Cooper B. Mental illness in a cross-national perspective. Results from a Brazilian and a German community survey among the elderly. Soc Psychiatry Psychiatr Epidemiol 1991; 26(6): 245-51.^,77. Borges DT, Dalmolin BM. Depressão em idosos de uma comunidade assistida pela Estratégia de Saúde da Família em Passo Fundo, RS. Rev Bras Med Fam Comunidade 2012; 7(23): 75-82.^,88. Rosa PV. Estudo sobre os fatores associados à depressão em idosos da comunidade de Barra Funda - RS [tese de doutorado]. Porto Alegre: Pontifícia Universidade do Rio Grande do Sul; 2007.^,99. Goncalves VC, Andrade KL. Prevalência de depressão em idosos atendidos em ambulatório de geriatria da região nordeste do Brasil (São Luís - MA). Rev Bras Geriatr Gerontol 2010; 13(2): 289-300.^,1010. Hoffmann EJ, Ribeiro F, Farnese JM, Lima EWB. Sintomas depressivos e fatores associados entre idosos residentes em uma comunidade no norte de Minas Gerais, Brasil. J Bras Psiquiatr 2010; 59(3): 190-7.^,1111. Maciel ACC, Guerra RO. Prevalência e fatores associados à sintomatologia depressiva em idosos residentes no Nordeste do Brasil. J Bras Psiquiatr 2006; 55(1): 26-33.^,1212. Bandeira CB. Perfil dos idosos com depressão em comunidade do município de Fortaleza. Rev Bras Med Fam Comunidade 2008; 4(15): 189-204.. The risk factors associated with their occurrence include being female, living alone, having low socioeconomic status, consuming alcohol in excess, having a chronic physical disorder, and referring to personal or family history of depression¹³13. Vink D, Aartsen MJ, Schoevers RA. Risk factors for anxiety and depression in the elderly: a review. J Affect Disord 2008; 106(1-2): 29-44.. The occurrence of family grief, cognitive impairment, and loss of functional mobility are other factors strongly associated with depression¹³13. Vink D, Aartsen MJ, Schoevers RA. Risk factors for anxiety and depression in the elderly: a review. J Affect Disord 2008; 106(1-2): 29-44.^,1414. Bruce ML. Psychosocial risk factors for depressive disorders in late life. Biol Psychiatry 2002; 52(3): 175-84.. Among the protective factors, there are social support, performing of social activities, especially volunteering, physical activities, and participation in religious activities¹⁵15. Hong SI, Hasche L, Bowland S. Structural relationships between social activities and longitudinal trajectories of depression among older adults. Gerontologist 2009; 49(1): 1-11.^,1616. Koenig HG. Religion and depression in older medical inpatients. Am J Geriatr Psychiatry 2007; 15(4): 282-91..

Most studies on depression in old age were carried out among elderly living in urban areas and large cities, where 85% of the Brazilian population lives. There are few studies on elderly living in small municipalities, especially in rural areas. Owing to the increased life expectancy, whether in small-, medium-, or large-sized municipalities, whether in rural or urban areas, it can be assumed that the elderly population will increase, as well as the prevalence of chronic noncommunicable diseases, such as depression, which is a chronic, recurrent, and incapacitating disorder which burdens the public health systems and changes the routine of families. In these municipalities, usually quite distant from large urban centers, the difficulties to deal with this kind of problem will be even greater, not only by the lack of qualified professionals, but also by the lack of infrastructure of the public health services.

The objective of the present study was to measure the prevalence and to identify factors associated to the occurrence of depression among all people aged 60 years or more living in the municipality of Arroio Trinta, Santa Catarina, Southern Brazil.

METHODS

This study was conducted in Arroio Trinta, Santa Catarina, Southern Brazil, a municipality colonized by Italians with about 3,500 inhabitants, located in Midwest Santa Catarina and 425 km far from Florianópolis, the state capital.

The target population of this study consisted of all those aged 60 years or more living in both the rural and urban areas of this municipality between the months of September and December 2013. The elderly who, due to physical or cognitive limitation, were unable to answer the questionnaire were excluded. Elderly who were traveling, hospitalized, or refused to take part in the study were accounted as losses.

This study was designed as a cross-sectional (or prevalence) study. This design is the most appropriate to quickly measure the occurrence of health or disease events at an acceptable cost at local level¹⁷17. Silva IS. Cancer epidemiology: principles and methods. Lyon: World Health Organization & International Agency for Research on Cancer; 1999..

The instrument applied consisted of a standardized and pre-coded questionnaire, which sought for information on demographic, environmental, behavioral, morbidity, and use characteristics of health services. The dependent variable (outcome) was built from the Geriatric Depression Scale Short Form (GDS-15). This scale presents a score which varies from 0 to 15 points. The cutoff point used in this study was 5/6 (no case/case). This cutoff point for the GDS-15 resulted, according to a previous study, in sensitivity rates of 85.4% and specificity ones of 73.9% for the diagnosis of greater depressive episode, according to ICD-10¹⁸18. Almeida OP, Almeida SA. Short versions of the geriatric depression scale: a study of their validity for the diagnosis of a major depressive episode according to ICD-10 and DSM-IV. Int J Geriatr Psychiatry 1999; 14(10): 858-65..

In order to apply this questionnaire, 14 students from a single high school in the municipality were recruited. These students were trained over five consecutive days in order to apply these questionnaires in households. At the end of the training period, 10 of them were chosen to perform the interviews. Initially, the municipality was divided into microareas. In the urban area, the division was defined according to streets, whereas in the rural area it was based on villages, rivers, bridges, mountains, or secondary roads.

In each of the households visited, the interviewer asked the age of the people living there to an adult. The answer was written down on a printed spreadsheet (conglomerate sheet). If there was someone aged 60 years or more, the student explained the study and invited them to participate in the study. On this occasion, an Informed Consent was offered for the resident to sign. Upon the acceptance to participate in the study, and after signing this term, the interviewers applied the questionnaire, which was unique, standardized, and with nearly all questions closed.

At the end of each day of work, the interviewers reviewed the questionnaires applied and, the following day, they delivered them in at the project’s headquarter, where they were reviewed and had their open questions codified. Next, these questionnaires were typed in twice and compared using the Epidata 3.1¹⁹19. Lauritsen JM. EpiData data entry, data management and basic statistical analysis system. Odense: EpiData Association; 2000-2008. and Epi Info¹⁷17. Silva IS. Cancer epidemiology: principles and methods. Lyon: World Health Organization & International Agency for Research on Cancer; 1999. softwares, respectively. Then, the data were analyzed in the statistical package Stata 11.2²⁰20. Stata Corp. Stata statistical software: release 11.2. College Station: Stata Corporation; 2011., with which the bivariate analysis was performed aiming to measure the level of association of the independent variables with the outcome (occurrence of depression according to the GDS-15). The χ² test was used to compare the proportions. The gross and adjusted analyses were performed using Poisson regression with robust variance²¹21. Barros AJ, Hirakata VN. Alternatives for logistic regression in cross-sectional studies: an empirical comparison of models that directly estimate the prevalence ratio. BMC Med Res Methodol 2003; 3: 21., according to the previously defined hierarchical model. Each set of variables of a certain level was included in the analysis, and all the variables whose p-value was ≤ 0.20 in relation to the outcome were kept in the model. The first level included the demographic and socioeconomic variables; the second level, the environmental variables; the third level included the variables related to health services utilization and to behavioral and morbidity aspects. This analysis model followed what was proposed by Victora et al.²²22. Victora CG, Huttly SR, Fuchs SC, Olinto MT. The role of conceptual frameworks in epidemiological analysis: a hierarchical approach. Int J Epidemiol 1997; 26(1): 224-7.. The statistical significance of each variable in the model was evaluated by the Wald’s test of heterogeneity and trend, according to their type²³23. Kirkwood BR, Sterne JAC. Essential medical statistics. Oxford: Blackwell; 2003..

The research projects was submitted and approved by the Health Research Ethics Committee (Comitê de Ética em Pesquisa na Área da Saúde - CEPAS) of the Universidade Federal de Pelotas (Process 320.865/2013).

RESULTS

Among the elderly, 568 were identified in the municipality of Arroio Trinta. Of this total, 5 refused to participate in the study, 11 were not found in their households, and 8 were not able to respond to the GDS-15. The responding rate was 96% (552 of 568).

Table 1 shows that approximately two thirds of this population lived in an urban area and were aged between 60 and 69 years, slightly above half of them (54%) were females and, most of them (93%) had white skin color; at least 7 out of 10 were married, 10% did not know how to read nor write, 53% of their families had a monthly income of at least 3 minimum wages, and 96% of them received retirement benefits. Also, in the same table, it is possible to verify that 8% were smokers, that is, had smoked at least 1 cigarette a day for the last 30 days; 28% practiced some kind of physical activity in the last 7 days; and 81% reported having participated regularly in some kind of leisure activity. Finally, 78% reported using some kind of medication daily, two thirds had consulted a doctor within the last 3 months, and approximately 1 out of 4 had been hospitalized or had some kind of fall in the last 12 months. Approximately two out of three claim, according to the diagnosis made by the doctor, having hypertension, diabetes mellitus, and/or depression (Table 1). The prevalence of depression according to the GDS-15 in the population studied was 20.4%, with a confidence interval of 95% (95%CI) 17.3 - 23.8.

Table 2 shows the prevalence of depression according to the category of the variable included in the model and the gross and adjusted analyses. The prevalence of depression in this population varied from 8.3%, among those who did not use any kind of medication daily or who did not take part in at least 3 leisure activities regularly, to 64.0%, among single elderly. In the gross analysis, almost all the variables in the model were proven significantly associated to the outcome, except for age, number of residents per household, and place of medical consultation. The adjusted analysis showed that the prevalence ratio (PR) for depression is substantially higher among women, among singles, the ones with lower family income, smokers, and the ones hospitalized in the last 12 months. This same adjusted analysis showed that the practice of physical activities in the last seven days, the participation in religious events and the performing of regular leisure activities acted out as protective factors against the occurrence of depression among elderly living in the municipality of Arroio Trinta, Santa Catarina, Southern Brazil.

DISCUSSION

One out of five elderly in Arroio Trinta suffers from depression, according to GDS-15. The greater risks for this condition were observed among those who were females, singles, with lower family income, smokers, and who consulted with a doctor and were hospitalized in the last 3-12 months prior to the interview, respectively. Taking part in religious events and performing some kind of physical and/or leisure activity regularly granted protection against the occurrence of depression.

Twenty percent of the elderly included in this study suffer from depression according to the scale used. The prevalence of depression among elderly depends on the scale and cutoff points used and the sociodemographic characteristics of the population studied. National studies which used the GDS-15 showed prevalences ranging from 21 to 50%⁷7. Borges DT, Dalmolin BM. Depressão em idosos de uma comunidade assistida pela Estratégia de Saúde da Família em Passo Fundo, RS. Rev Bras Med Fam Comunidade 2012; 7(23): 75-82.^,99. Goncalves VC, Andrade KL. Prevalência de depressão em idosos atendidos em ambulatório de geriatria da região nordeste do Brasil (São Luís - MA). Rev Bras Geriatr Gerontol 2010; 13(2): 289-300.^,1010. Hoffmann EJ, Ribeiro F, Farnese JM, Lima EWB. Sintomas depressivos e fatores associados entre idosos residentes em uma comunidade no norte de Minas Gerais, Brasil. J Bras Psiquiatr 2010; 59(3): 190-7.^,1111. Maciel ACC, Guerra RO. Prevalência e fatores associados à sintomatologia depressiva em idosos residentes no Nordeste do Brasil. J Bras Psiquiatr 2006; 55(1): 26-33.^,1212. Bandeira CB. Perfil dos idosos com depressão em comunidade do município de Fortaleza. Rev Bras Med Fam Comunidade 2008; 4(15): 189-204.. The studies which used ≥ 6 as a cutoff point for the outcome reached the highest prevalences (38 and 50%)⁹9. Goncalves VC, Andrade KL. Prevalência de depressão em idosos atendidos em ambulatório de geriatria da região nordeste do Brasil (São Luís - MA). Rev Bras Geriatr Gerontol 2010; 13(2): 289-300.^,1010. Hoffmann EJ, Ribeiro F, Farnese JM, Lima EWB. Sintomas depressivos e fatores associados entre idosos residentes em uma comunidade no norte de Minas Gerais, Brasil. J Bras Psiquiatr 2010; 59(3): 190-7.^,1111. Maciel ACC, Guerra RO. Prevalência e fatores associados à sintomatologia depressiva em idosos residentes no Nordeste do Brasil. J Bras Psiquiatr 2006; 55(1): 26-33.^,1212. Bandeira CB. Perfil dos idosos com depressão em comunidade do município de Fortaleza. Rev Bras Med Fam Comunidade 2008; 4(15): 189-204.. Although this study found a lower prevalence compared to the others - which may be due to differences related to the socioeconomic and demographic characteristics - the high prevalence of this disease is evident. It is, therefore, a common disease which requires proper management at individual level, but above all, at populational level.

Practicing physical activities in the seven days preceding the interview granted protection against the occurrence of depression in the population studied with PR = 0.62 (95%CI 040 - 0.97). There is enough evidence of beneficial effects of physical activities on depression in the elderly people. This protection may result from the psychological well-being caused by this interaction of the formation of affective relationship networks provided by this practice²⁴24. Gumarães JMN, Caldas CP. A influência da atividade física nos quadros depressivos de pessoas idosas: uma revisão sistemática. Rev Bras Epidemiol 2006; 9(4): 481-92.. A randomized controlled study showed that, when the individual feels less depressed, he or she would be more willing to remain physically active and, by doing so, the chance of the depressive symptoms to return is reduced²⁵25. Babyak MA, Blumenthal JA, Herman S, Khatri P, Doraiswamy M, Moore K, et al. Exercise treatment for major depression: maintenance of therapeutic benefit at 10 months. Psychosom Med 2000; 62(5): 633-8..

The PR for depression among elderly who are smokers compared to non-smokers was 1.75 (95%CI 1.11 - 2.77). This association has already been studied in different designs. Cohort studies show bidirectionality in this relation, meaning, depression may lead to smoking as well as this may lead to depression²⁶26. Munafo MR, Araya R. Cigarette smoking and depression: a question of causation. Br J Psychiatry 2010; 196(6): 425-6.. The fact is that, in Arroio Trinta, smoking and depression are strongly associated, and, as they are both undesirable to individuals, they must be fought against.

The PR for depression among women was 1.49 (95%CI 1.05 - 2.13) in relation to men. This finding is consistent to the ones found in other studies, according to which this higher risk of depression is due to an overload of women’s functions, especially the ones related to family (as a wife, mother, caretaker of the sick, educator, among others), to a higher widowhood rate, higher survival rate, social withdrawal, and estrogen deprivation²⁷27. Almeida OP. Idosos atendidos em serviço de emergência de saúde mental: características demográficas e clínicas. Rev Bras Psiquiatr 1999; 21(1): 12-8.^,2828. Tuesca-Molina R, Herrera NF, Sosa AM, Martínez FO, Arjona YP, Cueto JP, et al. Los grupos de socialización como factor protector contra la depresión en personas ancianas. Baranquilla, Colômbia. Rev Esp Salud Publica 2003; 77(5): 595-604..

Reaching old age as a single granted a PR = 3.63 (95%CI 2.32 - 5.70) for depression in relation to the ones who married at this age. Being single nearly always implies living alone and, therefore, loneliness, a condition associated to depression¹³13. Vink D, Aartsen MJ, Schoevers RA. Risk factors for anxiety and depression in the elderly: a review. J Affect Disord 2008; 106(1-2): 29-44.. Those who are married have, invariably, in addition to their partners, other family members as a result of this union. This leads to continuous interaction, dialog, and the exercise of living together, which contribute for the maintenance of the active individual and prevent introspection, which is a common condition in a depressive state⁸8. Rosa PV. Estudo sobre os fatores associados à depressão em idosos da comunidade de Barra Funda - RS [tese de doutorado]. Porto Alegre: Pontifícia Universidade do Rio Grande do Sul; 2007..

Elderly with income lower than 3 minimum wages showed approximately 70% higher PR for depression compared to those with higher income. Aging, particularly after the age of 60 years, leads to greater prevalence of degenerative chronic diseases and, therefore, greater expenses with health, especially medication. Furthermore, in Brazil, due to retirement, there is a substantial loss of purchasing power. The increase of expenses and the decrease of earnings lead to anxiety and concern among this population, which may contribute to both the onset and the maintenance of the depressive condition. This relation between family income and depression was evidenced in the National Household Sample Survey - Pesquisa Nacional por Amostra de Domicílios - (PNAD, 1998), which showed that 1% increase in per capita family income will decrease in 4% the risk of depression²⁹29. Bós AMG, Bós AJG. Fatores determinantes e consequências econômicas da depressão entre os idosos no Brasil. Rev Bras Ciên Envelhecimento Humano 2005; 2(2): 36-46..

Among the elderly who were identified as having depression according to the scale used, the PR for medical consultation in the last 3 months and hospitalization within the last 12 months was 1.66 (95%CI 1.12 - 2.45) and 1.55 (95%CI 1.12 - 2.14) times higher in relation to others, respectively. The PNAD revealed that the rate of hospitalization among the ones who claimed having depression was about 3 times higher in relation to others (18.0 versus 6.6%)³⁰30. Travassos C, Viacava F, Laguardia J. Os suplementos saúde na Pesquisa Nacional por Amostra de Domicílios (PNAD) no Brasil. Rev Bras Epidemiol 2008; 11(Suppl 1): 98-112.. This may be a reflex of the chronic condition of the disease, with a consequent use of health services³¹31. Máximo, GC. Aspectos sociodemográficos da depressão e utilização de serviços de saúde no Brasil [tese de doutorado]. Belo Horizonte: Universidade Federal de Minas Gerais; 2010..

Among the elderly in Arroio Trinta, taking part in a religious event decreases the risk of depression with PR = 0.69 (95%CI 0.51 - 0.96). Religiosity seems to act as an extremely important psychosocial factor for mental health. Having a religion, as well as attending churches, favors the preaching of solidarity, improving self-steem, and the potential for resilience³²32. Volcan SMA, Sousa PLR, Mari JJ, Horta BL. Relação entre bem-estar espiritual e transtornos psiquiátricos menores: estudo transversal. Rev Saúde Pública 2003; 37(4): 440-5..

The regular participation on leisure activities decreases the risk of depression in the studied population. For the elderly who participated in three or more leisure activities in the last 30 days, the protection reached 62% (PR = 0.38; 95%CI 0.20 - 0.69). It is widely known that taking part in a group (dance, games, trips, among others) for leisure is extremely positive, once it stimulates social integration, communication, exchange of experiences, and recreation. These activities help breaking down prejudices, decrease discrimination in relation to elderly and improve self-steem, which positively influences the mood.

CONCLUSION

The occurrence of depression in the municipality of Arroio Trinta is a common condition among the elderly studied. Despite not having identified a new risk or protection factor, this study corroborated the findings in great urban centers. In addition to that, it should be highlighted that this is a census with minimum losses, a rare event in other studies on the matter. These factors certainly need to be individually treated during medical consultation. However, promoting group activities actually seems indispensable, as the protection factors for depression are related to the interaction among the elderly. In this context, leisure activities should be prioritized, as beneficial effects are more evident in this type of activity. This is even more important in a municipality located far from a great urban area, which, by having an infrastructure focused only on basic care, does not provide, at local level, specialized care in this field and will hardly do so in the future. Finally, the need to assess the hypothesis raised on this study by means of a longitudinal design should be highlighted, in order to definitively solve this temporality limitation and, thus, permanently eliminate the bias of reverse causality which so much affects the approach of this problem in elderly population.

ACKNOWLEDGMENT

To the interviewers and elderly who participated in this study and to the Municipal Health Bureau (Secretaria Municipal de Saúde) of Arroio Trinta, Santa Catarina, Southern Brazil, for the logistical and financial support. Authors would also like to thank the comments of professors Juvenal Soares Dias da Costa from Universidade do Vale do Rio dos Sinos (UNISINOS) and Raul Mendoza-Sassi from Universidade Federal do Rio Grande (FURG).

References

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