Socioeconomic status is associated with frailty: the Women's Health and Aging Studies

Background: Frailty is a common risk factor for morbidity and mortality in older adults. Although both low socioeconomic status (SES) and frailty are important sources of vulnerability, there is limited research examining their relationship. A study was undertaken to determine (1) the extent to which low SES was associated with increased odds of frailty and (2) whether race was associated with frailty, independent of SES. Methods: A cross-sectional analysis of the Women's Health and Aging Studies using multivariable ordinal logistic regression modelling was conducted to estimate the relationship between SES measures and frailty status in 727 older women. Control variables included race, age, smoking status, insurance status and co-morbidities. Results: Of the sample, 10% were frail, 46% were intermediately frail and 44% were robust. In adjusted models, older women with less than a high school degree had a threefold greater odds of frailty compared with more educated individuals. Those with an annual income of less than $ 10 000 had two times greater odds of frailty than wealthier individuals. These findings were independent of age, race, health insurance status, co-morbidity and smoking status. African-Americans were more likely to be frail than Caucasians (p < 0.01). However, after adjusting for education, race was not associated with frailty. The effect of race was confounded by socioeconomic position. Conclusions: In this population-based sample, the odds of frailty were increased for those of low education or income regardless of race. The growing population of older adults with low levels of education and income renders these findings important.