ABSTRACT
Psychological depression is an independent risk factor for coronary artery disease. C-reactive protein has been implicated as a mediator of the effect of psychological depression. Several studies have found that individuals, especially men, who report higher levels of psychological depression also have higher levels of C-reactive protein. The current study was undertaken to replicate these results in a Brazilian population, in which there is a much wider range of variation in both background characteristics (such as socioeconomic status) and coronary artery disease risk factors. A sample of 271 individuals was interviewed using the Center for Epidemiological Studies Depression Scale. Fasting blood samples were obtained and evaluated for C-reactive protein (assessed by a turbidimetric immunoassay using a Dade Behring kit) analysis in a subsample (N = 258) of individuals. The mean ± SD C-reactive protein for the entire sample was 0.43 ± 0.44, with 0.42 ± 0.48 for men and 0.43 ± 0.42 mg/L for women. Data were analyzed using multiple regression analysis, controlling for age, sex, body mass index, socioeconomic status, tobacco use, and both total cholesterol and low-density lipoprotein cholesterol. Higher reported depressive symptoms were correlated with higher C-reactive protein for men (partial r = 0.298, P = 0.004) and with lower C-reactive protein for women (partial r = -0.154, P = 0.059). The differences in the associations for men and women could be a result of differential effects of sex hormones on stress reactivity and immune response. On the other hand, this difference in the associations may be related to gender differences in the disclosure of emotion and the effect that self-disclosure has on physical health and immune response.
Subject(s)
Adult , Female , Humans , Male , C-Reactive Protein/analysis , Depressive Disorder/blood , Brazil , Biomarkers/blood , Immunoassay , Interviews as Topic , Multivariate Analysis , Nephelometry and Turbidimetry , Risk Factors , Sex Factors , Socioeconomic Factors , Urban PopulationABSTRACT
Objective: To examine socioeconomic variables in relation to three indices of adult body composition: the body mass index: and, percent body fat and lean-to-fat body mass ratio, both derived from bioelectric impedance analysis. Purpose: To investigate the relationship between obesity and socioeconomic variables in a developing country. Research methods and procedures: A cross-sectional survey of four neighborhoods differing in socioeconomic status. A random sample of 304 healthy adults, 181 females and 123 males, age range 18-78. Body composition was measured with the body mass index derived from height and weight, and the assessments of percent body fat and the ratio of lean-to-fat body mass derived from bioelectric impedance analysis. Results: Using a linear model with age as a covariate and sex as an additional factor, there were significant interaction effects between sex and socioeconomic group for all three of the body composition variables (p < 0,005). Analysis of trends within sex revealed primarily a linear association between socioeconomic group and body composition for males (p < 0,001), and a curvilinear association between socioeconomic group and body composition for females (p < 0.03). Discussion: The association of socioeconomic status and body composition is significant for males and females, but the pattern of the association varies by gender. It is argued that these results can be explained by three processes: socioeconomic differences in caloric demands of labor: socioeconomic differences in the social value attached to food: and, gender differences in standards of physical attractiveness