Association of Visual Impairment and All-Cause 10-Year Mortality Among Indigenous Australian Individuals Within Central Australia: The Central Australian Ocular Health Study

IMPORTANCE It is well established from different population-based studies that visual impairment is associated with increased mortality rate. However, to our knowledge, the association of visual impairment with increased mortality rate has not been reported among indigenous Australian individuals. OBJECTIVE To assess the association between visual impairment and 10-year mortality risk among the remote indigenous Australian population. DESIGN, SETTING, AND PARTICIPANTS Prospective cohort study recruiting indigenous Australian individuals from 30 remote communities located within the central Australian statistical local area over a 36-month period between July 2005 and June 2008. The data were analyzed in January 2017. EXPOSURES Visual acuity, slitlamp biomicroscopy, and fundus examination were performed on all patients at recruitment. Visual impairment was defined as a visual acuity of less than 6/12 in the better eye. MAIN OUTCOMES AND MEASURES Mortality rate and mortality cause were obtained at 10 years, and statistical analyses were performed. Hazard ratios for 10-year mortality with 95% confidence intervals are presented. RESULTS One thousand three hundred forty-seven patients were recruited from a total target population number of 2014. The mean (SD) age was 56 (11) years, and 62% were women. The total all-cause mortality was found to be 29.3% at 10 years. This varied from 21.1% among those without visual impairment to 48.5% among those with visual impairment. After adjustment for age, sex, and the presence of diabetes and hypertension, those with visual impairment were 40% more likely to die (hazard ratio, 1.40; 95% CI, 1.16-1.70; P = .001) during the 10-year follow-up period compared with those with normal vision. CONCLUSIONS AND RELEVANCE Bilateral visual impairment among remote indigenous Australian individuals was associated with 40% higher 10-year mortality risk compared with those who were not visually impaired. Resource allocation toward improving visual acuity may therefore aid in closing the gap in mortality outcomes between indigenous and nonindigenous Australian individuals.