Association of disability with mortality in the Spanish adult non-institutionalised population

Abstract

Background: There are scant studies focused on measuring the association between disability and all-cause mortality based on large representative national samples of the community-dwelling adult population; moreover, the number of such studies which also include cause-specific mortality is yet lower. Methods: Longitudinal cohort study that used baseline data from 162 381 adults who participated in a countrywide disability survey (2008). A nationally representative sample was selected and interviewed in their homes. We present data on people ≥18 years. Disability was considered as any substantial limitation found on a list of 44 life activities that have lasted or are expected to last more than 1 year and originate from an impairment. Cause-specific mortality data were obtained from the Spanish Statistical Office. Subjects contributed follow-up time from baseline interview until death or the censoring date (31 December 2017). We computed standardised rate ratios (SRRs), with age, sex, living with a partner and education level distribution of the total group as standard population. Results: Adults with disability (11%) had an adjusted mortality rate more than twice as high as adults without disability (SRR 2.37, 95% CI 2.24 to 2.50). The increased mortality risk remained over the 10-year follow-up period. Mortality due to diseases of the nervous system (SRR 4.86, 95% CI 3.93 to 6.01), diseases of the musculoskeletal system (SRR 3.45, 95% CI 2.18 to 5.47), infectious diseases (SRR 3.38, 95% CI 2.27 to 5.01) and diabetes mellitus (SRR 3.56, 95% CI 2.71 to 4.68) was particularly high in those with disability. Conclusions: All-cause mortality rates are markedly higher among adults with disability. Preventive measures and health promotion initiatives are needed to reduce mortality risk in this population. Special attention should be paid to disabled people with certain specific diseases.