Income differences in the type of antihypertensive medicines used in ambulatory settings in Finland: a register-based study.

PURPOSE: The objective of this study was to explore income differences in the prevalence of moderate-to-severe hypertension, and among patients, in the use and costs of medicines.

METHODS

Personal income was used to classify ≥25-year-old population in quintiles (QI-QV). Patients (N = 497,560) with moderate-to-severe hypertension were identified using special refund entitlements. Medicine use and costs derived from prescription register. Direct standardisation and multivariate regression were used to adjust for demographics and comorbidities.

RESULTS

Low income was associated with higher prevalence of moderate-to-severe hypertension (overall 13%). After adjusting for age, gender, residence, diabetes and coronary heart disease, nearly all patients purchased at least one antihypertensive medicine (93 vs. 96% in QI and QV). Differences in the purchased quantities were small (mean estimates 1028 vs. 1054 defined daily doses (DDDs)/patient/year in QIV and QI). High-income patients were more likely to use angiotensin receptor blockers (37 vs. 54% in QI and QV). Low-income patients were more likely to use beta-blockers (59 vs. 49%, respectively) and ACE inhibitors (35 vs. 28%, respectively). Higher income was associated with higher annual out-of-pocket costs (mean €66 vs. €71 in QI and QV) and reimbursements (€144 vs. €163, respectively).

CONCLUSIONS

Use of more expensive medicines contributed to higher costs among patients with higher incomes.