• The Chronic Kidney Disease Epidemic in El Salvador: A Cross-Sectional Study Original Research

    Orantes-Navarro, Carlos Manuel; Almaguer-López, Miguel M.; Alonso-Galbán, Patricia; Díaz-Amaya, Moisés; Hernández, Samuel; Herrera-Valdés, Raúl; Silva-Aycaguer, Luis Carlos

    Abstract in English:

    ABSTRACT INTRODUCTION Chronic kidney disease has reached epidemic levels in several Central American countries since the early years of this century. In El Salvador, it is the second cause of death in men, the fifth in persons over 18 years old and the third cause of hospital deaths in the adult population. Its features, especially those of a subtype unassociated with traditional risk factors such as diabetes and high blood pressure, are only partially understood. OBJECTIVE Estimate the magnitude of chronic kidney disease in the adult population of El Salvador, considering both prevalence of the disease in its diverse forms as well as presence of potential risk factors nationally and in major subpopulations. METHODS A descriptive, cross-sectional analysis was conducted on data obtained from the Survey of Chronic Non-communicable Diseases in Adults in El Salvador, completed in 2015. The original data (interviews and measurements) were collected between October 2014 and March 2015 from 4817 adults employing a two-stage probabilistic cluster sample, with stratification of primary sampling units. Our analysis, using 20 of the 118 primary variables included in the original survey, focused on point estimation of prevalence rates and means, related to both traditional biological risk factors and nontraditional ones, such as insufficient hydration, strenuous working conditions and exposure to toxic agents. A separate analysis was performed to estimate prevalence of chronic kidney disease from nontraditional causes. Corresponding confidence intervals were calculated with proper weighting. RESULTS The general prevalence of chronic kidney disease in El Salvador was 12.8% (men 18.0%; women 8.7%). Of the chronically ill kidney patients, 13.1% were between 20 and 40 years of age. Among biological risk factors, the most frequent was high blood pressure (37.0%). Among nontraditional risk factors, high levels of sugary drink consumption (81.0%), insufficient hydration (65.9%) and high levels of exposure to agrochemicals in the work environment (12.6%) were also observed. Prevalence of chronic kidney disease from nontraditional causes was 3.9% (men 6.1%; women 2.2%). CONCLUSIONS Chronic kidney disease has reached epidemic proportions in El Salvador. The data confirm a health tragedy that, although especially striking older men, also takes a severe toll on young men and women. The results confirm findings of previous research in several Salvadoran agricultural communities. The relatively high level of population exposure to agrochemicals is important and alarming, especially in rural areas, meriting health-impact studies that include and go beyond possible impact on chronic kidney disease.
  • Normal Values of T, B and NK Lymphocyte Subpopulations in Peripheral Blood of Healthy Cuban Adults Original Research

    Kokuina, Elena; Breff-Fonseca, Martha C.; Villegas-Valverde, Carlos A.; Mora-Díaz, Isabel

    Abstract in English:

    ABSTRACT INTRODUCTION Quantification of lymphocyte subpopulations is useful for evaluating immune response in states of health and disease, including immunodeficiencies, autoimmunity, infections and cancer. Studies have found that concentrations and proportions of different cell subpopulations vary with geographic location, age, sex and ethnicity. Knowing the normal values of these cells and their variation in healthy populations will contribute to improved clinical practice and scientific research. OBJECTIVE Estimate normal absolute concentrations and percentages of the most abundant lymphocyte subpopulations in peripheral blood and their relation to sex and age. METHODS A cross-sectional analysis was conducted in 129 healthy adults, 61 men and 68 women aged 18–80 years; 89 aged <50 years and 40 ≥50 years. We included individuals who agreed to participate by written informed consent. Exclusion criteria were chronic disease, or use of tobacco, alcohol or medications that can alter immune system cell numbers and functions. Through dual platform flow cytometry, we determined absolute and percentage values for T lymphocyte subsets CD3+, CD3+/CD4+T, CD3+/CD8+T, CD19+ B cells and CD3-/CD56+ natural killer cells in peripheral blood, using an 8-color flow cytometer. We estimated medians and the 2.5 and 97.5 percentiles and calculated the Pearson correlation coefficient to evaluate associations. Significance tests were also used to compare groups. The significance threshold was p = 0.05 in all cases. RESULTS Ranges of absolute values and percentages (%) were: total lymphocytes: 1200–3475 cells/μL (20.2–49.3); CD3+ T cells: 880–2623 cells/μL (56.5–84.7); CD3+/CD4+ T cells: 479–1792 cells/μL (30.3–55.7); CD3+/CD8+ T cells: 248–1101 cells/μL (13.2–42.9); CD19+ B cells: 114– 1491 cells/μL (5.4–49.5); CD3-/CD56+ natural killer cells: 70–652 cells/μL (3.7–28.0); and the CD4+:CD8+ index: 0.80–3.92. Absolute numbers–– but not percentages––of lymphocytes and CD3+ T cells were higher in those <50 years (p = 0.025 and 0.020, respectively). Absolute values and relative percentages of CD3+/CD8+ and relative values of CD3+/CD4+ T cells were significantly higher in the younger subgroup (p = 0.004 and p = 0.047). Age was not associated significantly with B lymphocytes or natural killer cells. Absolute and relative values of CD3+/CD4+ T lymphocytes were significantly higher in women (p = 0.009 and 0.036, respectively). CONCLUSIONS Absolute numbers of total lymphocytes and T and CD3+/CD8+ T lymphocytes are higher in younger individuals. In percentage values, CD3+/CD4+ T lymphocytes are lower in older persons. Absolute and percentage values of CD3+/CD4+ T phenotype are higher in women. These differences justify adjusting clinical analyses to different values by age and sex.
  • Corrected QT-Interval Dispersion: An Electrocardiographic Tool to Predict Recurrence of Myocardial Infarction Original Research

    Rodríguez-Jiménez, Ailed Elena; Cruz-Inerarity, Hugo; Negrín-Valdés, Tessa; Fardales-Rodríguez, Raikel; Chávez-González, Elibet

    Abstract in English:

    ABSTRACT INTRODUCTION Many clinical settings lack the necessary resources to complete angiographic studies, which are commonly used to predict complications and death following acute coronary syndrome. Corrected QT-interval dispersion can be useful for assessing risk of myocardial infarction recurrence. OBJECTIVE Evaluate the relationship between corrected QT-interval dispersion and recurrence of myocardial infarction in patients with ST- segment elevation. METHODS We conducted a prospective observational study of 522 patients with ST-segment elevation myocardial infarction admitted consecutively to the Camilo Cienfuegos General Provincial Hospital in Sancti Spiritus, Cuba, from January 2014 through June 2017. Of these, 476 were studied and 46 were excluded because they had other disorders. Demographic variables and classic cardiovascular risk factors were included. Blood pressure, heart rate, blood glucose, and corrected and un- corrected QT-interval duration and dispersion were measured. Patients were categorized according to the Killip-Kimball classification. Association between dispersion of the corrected QT-interval and recurrence of infarction was analyzed using a binary logistic regression model, a regression tree and receiver operator characteristic curves. RESULTS Patients with recurrent infarction (56; 11.8%) had higher average initial blood glucose values than those who did not have recurrence; the opposite occurred for systolic and diastolic blood pressure and for left ventricular ejection fraction. Dispersion of the corrected QT-interval was a good predictor of infarction recurrence according to a multivariate analysis (OR = 3.09; 95% CI = 1.105–8.641; p = 0.032). Cardiac arrest is the variable that best predicts recurrence. No recurrence of infarction occurred in 97% of patients without cardiac arrest, left ventricular ejection fraction >45% and corrected QT- interval dispersion <80 ms. CONCLUSIONS Risk of infarction recurrence is low in patients without cardiac arrest, with left ventricular ejection fraction >45% and with dispersion of corrected QT-interval <80 ms. Patients with corrected QT-interval dispersion ≥80 ms have greater risk of recurrence of infarction, which suggests that this variable could be used for stratification of risk following ST-segment elevation myocardial infarction.
  • Biochemical Markers and Hypertension in Children Original Research

    Garí-Llanes, Merlin; García-Nóbrega, Yosvany; Chávez-González, Elibet; González-Rodríguez, Emilio; García-Sáez, Julieta; Llanes-Camacho, María del Carmen

    Abstract in English:

    ABSTRACT INTRODUCTION Hypertension is one of the most studied risk factors for cardiovascular disease in adults; in children and adolescents, its global prevalence changes with age, from 1%-3% in children to 3.2% in adolescents. In adults, in addition to hypertension, several biochemical markers of cardiovascular risk have been identified. Confirming an association between these and hypertension in childhood and adolescence would allow for more timely diagnosis and monitoring of cardiovascular disease, since the presence of both the markers and hypertension would imply increased risk. OBJECTIVE Confirm an association between biochemical risk markers of cardiovascular disease and hypertension in children aged 8 to 11 years. METHODS A cross-sectional study of 373 children aged 8-11 years was conducted in 3 primary schools in the city of Santa Clara in central Cuba. The variables examined were age, sex, height, blood pressure, cholesterol, triglycerides, lipoproteins and apolipoproteins. The children were classified as normotensive, prehypertensive or hypertensive, based on blood pressure readings and percentiles for age, sex and height. Descriptive statistics were calculated for quantitative variables. A bivariate analysis, tests of independence for qualitative variables and a means comparison for quantitative variables (ANOVA and its nonparametric alternative, the Kruskal Wallis test) were performed. Fisher’s F-test and its associated probability value were employed. RESULTS Some 32.2% of the children were prehypertensive and 5.1% hypertensive. Cholesterol and triglyceride values were significantly higher in hypertensive than in normotensive children (p = 0.028 and p = 0.047, respectively). HDL numbers were higher in normotensive children (p = 0.001), and LDL numbers and the LDL/ HDL ratio were higher in the hypertensive children, with differences between groups (p = 0.001 for both variables). There were differences between the three blood pressure categories for lipoprotein(a) and ApoA (p <0.001 and p = 0.001), for ApoB and for the ApoB/ApoA ratio (p <0.001 for both variables), with lower ApoA values and higher ApoB and ApoB/ApoA values in the hypertensive children. CONCLUSIONS The biochemical risk markers most strongly associated with hypertension in children are ApoB values, LDL, lipoprotein(a), and LDL/HDL and ApoB/ApoA ratios.
  • Pharmacogenetic Markers: A Path toward Individualized HIV Therapy Original Research

    García-Blanco, Danays; Gravier-Hernández, Rosario; Rabeiro-Martínez, Carlos L.; Valle, Lizette Gil del; Pérez-Ávila, Jorge

    Abstract in English:

    INTRODUCTION Approximately 73% of persons with HIV who receive antiretroviral therapy in Cuba are in viral suppression. The non-response of the remaining 27% could be due to several factors including adverse drug reactions and HIV resistance to antiretroviral drugs, as well as social factors and idiosyncratic characteristics of each patient. Genetic information explains from 20% to 95% of a drug’s effects and variations in response. Considering optimization of therapeutic efficacy in our country, genetic factors of the host should be identified. OBJECTIVE Identify polymorphisms affecting genetic variability of responses to antiretroviral drugs. EVIDENCE ACQUISITION A literature review was conducted (of original articles, published theses, clinical reports and bibliographic review studies, from 2000 to 2018, in Spanish and English listed in MEDLINE/PubMed, SciELO, LILACS, PharmGKB and Google Scholar) with the following key words: pharmacogenetics, human immunodeficiency virus, anti-retroviral agents, genetic polymorphism, genetic techniques, pharmacogenomic variants. DEVELOPMENT The review identified 77 relevant publications meeting specific quality criteria. A summary table was built with data collected on antiretroviral drugs, genes and proteins involved in polymorphic variations, their associated effects and relevant scientific references. Information was included on polymorphisms related to 12 antiretroviral drugs used in HIV therapy. Polymorphisms determine variations in proteins involved in drug transport and metabolism and in elements of immunity. Relevant pharmacogenetic biomarkers recognized by drug regulatory agencies were identified. CONCLUSIONS The study identified genetic variations (single-nucleotide polymorphisms) associated with 12 antiretroviral drugs. In most cases, no statistically significant causal association was found. Identifying polymorphic variations is a medium- and long-term objective that requires statistical support and adoption of strategies to optimize antiretroviral therapy. An approach combining plasma-level monitoring and pharmacogenetic analysis is recommended to optimize therapy for HIV patients.
  • Assistive Devices for Older Adults: A Longitudinal Study of Policy Effectiveness, Santiago, Chile, 2014–2016 Original Research

    Hirmas-Adauy, Macarena; Olea, Andrea; Matute, Isabel; Delgado, Iris; Aguilera, Ximena; Poffald, Lucy; González, Claudia; Nájera, Manuel; Gómez, María Inés; Gallardo, Ligia; Abusleme, María Teresa; Leppe, Jaime; Mery, Hernán; Recabarren, Eladio; Massad, Cristián; Bustamante, Hernán

    Abstract in English:

    ABSTRACT INTRODUCTION Population aging is a worldwide phenomenon. It is estimated that by 2050, one of five persons will be aged ≥60 years. In Chile, 15.8% of the population is now aged ≥60 years, and this figure will reach 30.7% by 2050. In 2006, a national program was implemented to provide assistive devices to older adults aged ≥65 years with limited mobility or difficulty performing activities of daily living. To date, there have been no assessments of the program’s effectiveness. OBJECTIVE Assess the effectiveness of an assistive devices policy in Chile on improving functional capacity of older adults aged ≥65 years, and beneficiaries’ perceptions of the services received, including changes in their quality of life. METHODS This was a before–after longitudinal study. A cohort of 309 persons was recruited, consisting of patients who received care at a public hospital in Santiago, Chile during 2014–2015. They were assessed before delivery of assistive devices, then followed for seven months, with repeated evaluations made in their homes. The following indicators were measured: functional capacity (Tinetti scale and Barthel Index); changes in perceived quality of life related to use of assistive devices; and other sociodemographic, clinical and protocol-compliance variables. A longitudinal analysis of before–after progress was carried out, as well as a description of service delivery and medical followup. RESULTS Sixty-eight percent of those surveyed were women; median age was 74 years, average schooling was 6 years, and 93% had low income (monthly income <US$398). Assistive devices increased independence in activities of daily living, improved mobility and perceived quality of life, and decreased fall risk and pain. One hundred percent felt satisfied with the service received, 91% were trained in use of the device, and delivery deadlines were met in 83% of cases, but only 2% were followed up. One negative aspect is that the program covers only 25% of estimated need. CONCLUSIONS This assistive device program helps improve functional capacity and perceived quality of life in vulnerable patients who are able to access it. It addresses a real need and is highly valued by patients. Although delivery schedules were fulfilled, followup care schedules were not.
  • Dengue Cases in Colombia: Mathematical Forecasts for 2018–2022 Original Research

    López-Montenegro, Luis Eduardo; Pulecio-Montoya, Ana María; Marcillo-Hernández, Germán Arturo

    Abstract in English:

    INTRODUCTION Dengue is a disease caused by any one of five virus serotypes and transmitted to humans by the Aedes aegypti mosquito. Climate change and health conditions have combined to make dengue a global public health problem. The situation is especially serious in Colombia, where by week 36 of 2018, dengue incidence was 96 cases per 100,000 population, with a total of 111 deaths. Different mathematical and statistical models have been proposed to understand the dynamics of transmission and consequently to apply control strategies to reduce the number of dengue cases. OBJECTIVE Forecast the number of dengue cases expected in Colombia from 2018 through 2022 with the stochastic Auto-Regressive Integrated Moving Average (ARIMA) model and use the results to adjust the parameters of an ordinary differential equations model in order to determine the disease’s basic reproduction number in the year presenting the highest number of dengue cases. METHODS An ecological time series study was conducted to forecast dengue incidence in Colombia from 2018 through 2022. The data were compiled from Colombia’s National Health Institute series on dengue cases reported by epidemiological week from 2009 to 2017. The stochastic ARIMA time series model was applied. Forecasts were then analyzed, and the year with the highest number of predicted cases was used to adjust the parameters of an ordinary differential equations model (ODE) through nonlinear least squares regression to calculate the vectorial capacity of the transmitting mosquito. RESULTS Forecasts of the total number of dengue cases per year in Colombia for the following five years were: 32,411 (2018); 88,221 (2019); 56,392 (2020); 47,940 (2021); and 77,344 (2022). The highest number of cases was forecast for 2019. Values for the parameters affecting dengue transmission that year (by the year’s four quarters), such as recovery rate (0.0992, 0.0838, 0.1177, and 0.1535, respectively), vectorial capacity of the transmitting mosquito (0.1720, 0.1705, 0.1204, and 0.2147, respectively) and the basic dengue reproduction number (1.73, 2.03, 1.02, and 1.40, respectively) were estimated, indicating that most cases would occur in the second quarter and, since the basic reproduction number values were >1, the disease would persist in the country throughout the entire year. CONCLUSIONS ARIMA model forecasts for 2018 through 2022 predicted the highest incidence of dengue cases in Colombia would occur in 2019. Comparison of ARIMA model forecasts and the ODE model allowed projections of possible variations in dengue cases reported, and the basic reproduction number predicted that dengue would persist throughout 2019.
Medical Education Cooperation with Cuba Oakland - California - United States
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