Small area-level socioeconomic status and all-cause mortality within 10 years in a population-based cohort of women: Data from the Geelong Osteoporosis Study

BACKGROUND: The social gradient of health and mortality is well-documented. However, data are scarce regarding whether differences in mortality are observed across socio-economic status (SES) measured at the small area-level. We investigated associations between area-level SES and all-cause mortality in Australian women aged ≥ 20 years. METHODS: We examined SES, obesity, hypertension, lifestyle behaviors and all-cause mortality within 10 years post-baseline (1994), for 1494 randomly-selected women. Participants' residential addresses were matched to Australian Bureau of Statistics Census data to identify area-level SES, and deaths were ascertained from the Australian National Deaths Index. Logistic regression models were adjusted for age, and subsequent adjustments made for measures of weight status and lifestyle behaviors. RESULTS: We observed 243 (16.3%) deaths within 10 years post-baseline. Females in SES quintiles 2–4 (less disadvantaged) had lower odds of mortality (0.49–0.59) compared to SES quintile 1 (most disadvantaged) under the best model, after adjusting for age, smoking status and low mobility. CONCLUSIONS: Compared to the lowest SES quintile (most disadvantaged), females in quintiles 2 to 5 (less disadvantaged) had significantly lower odds ratio of all-cause mortality within 10 years. Associations between extreme social disadvantage and mortality warrant further attention from research, public health and policy arenas.