Gender differences in health-related quality of life among the elderly: the role of objective functional capacity and chronic conditions.

Although worse Health-Related Quality of Life (HRQL) among women has been widely described, it remains unclear whether this is due to differential reporting patterns, or whether there is a real difference in health status. The objective of this study was to evaluate to what extent gender differences in HRQL among the elderly might be explained by differences in performance-based functional capacity and chronic conditions, using the conceptual model of health outcomes as proposed by Wilson and Cleary. Data are from a cross-sectional home survey of 872 surviving individuals from an elderly cohort representative of Barcelona's general population. Complete valid data for these analyses were obtained from 62% of the subjects (n = 544). The evaluation included the Nottingham Health Profile (NHP), a generic measure of HRQL; three performance-based functional capacity tests (balance, chair-stand, and walking tests); and a standardized list of self-reported chronic conditions. A series of multiple linear regression models were built with the total NHP score as the dependent variable, with gender, socio-demographic information, performance-based functional capacity and chronic conditions included sequentially, as independent variables. Women (65.4%) showed worse results than men on HRQL (mean of NHP total score 28.3 vs 16.7, p < 0.001) and functional capacity (mean of summary score 7.1 vs 8.3, p < 0.001). Functional capacity, arthritis, back pain, diabetes, and depression were significantly associated to the NHP total score in the final regression model, which explained 42% of the variance. Raw differences by gender in the total NHP score were 11.5 points (p < 0.001), but decreased to a non-significant 3.2 points (p = 0.18) after adjusting for all the other variables. In conclusion, our data suggest that worse reported HRQL in elderly women is mainly due to a higher prevalence of disability and chronic conditions.