Disability, more than multimorbidity, was predictive of mortality among older persons aged 80 years and older

In this study, we evaluate the impact of disability and multimorbidity on the risk of all-cause death in a population of frail older persons living in community.

We analyzed data from the Aging and Longevity Study in the Sirente geographic area, a prospective cohort study that collected data on all subjects aged 80 years and older (n=364). The main outcome measure was all-cause mortality over 4-year follow-up.

A total of 150 deaths occurred. Sixty-seven subjects (44.6%) died in the nondisabled group compared with 83 subjects (55.3%) in the disabled group (P<0.01). Thirty-nine subjects (31.7%) died among subjects without multimorbidity compared with 111 subjects (46.0%) with two or more diseases (P<0.01). When examining the combined effect of multimorbidity and disability, the effect of disability on the risk of death was higher than that of multimorbidity. After adjusting for potential confounders, relative to those without disability and multimorbidity, disabled subjects showed an increased risk of death when multimorbidity was associated (hazard ratio [HR]=3.91; 95% confidence interval [CI]=1.53-10.00) and in absence of multimorbidity (HR=2.36; 95% CI=0.63-8.83).

Our results show that disability exerts an important influence on mortality, independently of age and other clinical and functional variables.