306Association between polypharmacy and mortality in the community-dwelling older population: a data linkage study

Background Literature findings on the association between polypharmacy and mortality in older people are not consistent. Appropriate tools, making use of linkages, are helpful to investigate this further. Methods Data of participants of the Belgian Health Interview Survey 2013 aged ≥ 65 years (n = 1950) were linked with billing data and 5 year’s mortality follow-up information. Polypharmacy was defined as concomitant use of ≥ 5 medicines in the past 24 hours or ≥ 5 recent prescriptions of reimbursed medicines. The impact of polypharmacy on mortality was assessed through mortality rate ratios (MRR) from a Poisson regression model adjusting for gender, age, multimorbidity, functional limitations and health care use, and including interactions. Results The prevalence of polypharmacy was 38,3%. Age and disability status were effect modifiers in the association between polypharmacy and mortality. Whereas polypharmacy was significantly associated with mortality among people aged 65-79 years (MRR 2.52; 95% CI 1.67-3.80), this was not so for the 80 + (MRR 1.46; 95% CI 0.93-2.29). Polypharmacy was a mortality predictor among people with no/moderate functional limitations (MRR 2,29; 95% CI 1.61-3.25), but not for those with severe functional limitations (MRR 1,22; 95% CI 0.67-2.34). Conclusions By linking health interview survey, billing and mortality data further insights can be gained on the association between polypharmacy and mortality. Key messages A critical evaluation of polypharmacy in older people below 80 years and in people without severe functional limitations may reduce mortality in these population groups.