Out-of-pocket prescription medicine expenditure amongst community-dwelling adults: findings from The Irish Longitudinal Study on Ageing (TILDA) in 2016

Background The number of prescription medicines prescribed to older adults is increasing in Ireland and other countries. This is leading to higher out-of-pocket prescription medicine expenditure for older adults, which has several negative consequences including cost-related non-adherence. This study aimed to characterise out-of-pocket prescription medicine payments, and examine their relationship with entitlements, multimorbidity and adherence. Methods This cross-sectional study used 2016 data from a nationally-representative sample of adults in Ireland aged 50 years or less. Descriptive statistics and regression models were used to describe out-of-pocket prescription medicine payments and assess the association between out-of-pocket prescription medicine payments and the following variables: healthcare entitlements, multimorbidity, and cost-related non-adherence. Results There were 5,668 eligible participants. Median annual out-of-pocket prescription medicine expenditure was 144 euro (IQR: 0-312 euro). A generalised linear model showed that, amongst those with out-of-pocket prescription medicine expenditure, having fewer healthcare entitlements was associated with 4.74 (95% CI: 4.37-5.15) times higher out-of-pocket prescription medicine expenditure. Overall, 1.7% (n=89) of participants reported cost-related non-adherence in the previous year. A multivariable model found no significant associations between any variables and cost-related non-adherence. Conclusions Those with entitlements to subsidised prescription medicines had much lower out-of-pocket prescription medicine expenditure. This highlights the benefits of expanding healthcare entitlements and ensuring uptake of entitlements by those with eligibility.