A higher adherence to perindopril-based anti-hypertensive therapy is associated with a reduced risk of cardiovascular outcomes and all-cause mortality in real clinical practice in Italy

Abstract Background Therapeutic management of hypertension is a landmark of cardiovascular (CV) risk prevention. Combined therapies with at least 2 anti-hypertensive agents are required in many patients in whom monotherapy and lifestyle interventions failed in blood pressure control. It is well-known that poor medication adherence remains a major barrier to achieving the therapeutic targets for all CV drugs, including anti-hypertensives. Purpose We evaluated the relationship between adherence to perindopril (PER)-based therapeutic regimen prescribed as single-pill combination (SPC) or free-pill and CV outcomes and all-cause mortality in a large Italian population. Methods A retrospective analysis was performed using administrative databases corresponding to around 6.7 million health-assisted residents. Hypertensive adults were first identified through hospitalization discharge diagnosis or exemption codes for hypertension between 2010 and 2021. Patients prescribed PER-based therapies were screened for all combinations of PER with amlodipine (AML) and/or indapamide (IND) (all formulations, single-pill or free-pill). Time of the first prescription of a PER-based regimen during the inclusion period was considered the index-date. The analysis included all hypertensive subjects prescribed a PER-based therapy, having available data at least 12 months before and 24 months after the index-date, respectively. Since the analysis was focused on the possible associations between adherence level and CV outcomes and all-cause mortality, adherence was assessed during the first year of follow-up on alive patients and outcomes were assessed during the second year. Adherence was assessed using the proportion of days covered (PDC) approach on 1-year follow-up, and considering a PDC<80% as poor-to-moderate adherence, and PDC ≥80% as good adherence. The Cox’s proportional hazard model was applied to estimate Hazard Ratio (HR) adjusting for baseline covariates, including comorbidity profile and pill burden. Results The included cohort (N=24,476) was divided into sub-groups according to adherence in poor-to-moderate (N=6,781) and good adherent patients (N=17,695) with a mean age of 64.8±13.3 and 64.6±11.9 years old, respectively. The Cox’s proportional hazard model showed that good adherence was associated with a relative risk reduction of 23% in all-cause mortality (Table 1A), 21% in all CV events (Table 1B), 17% in ischemic heart disease (Table 1C), 33% in cerebrovascular events (Table 1E), and 22% in the composite outcome of CV events/all-cause mortality (Table 1G). Conclusions The present analysis provided evidence from the Italian real clinical practice that good adherence to PER-based anti-hypertensive therapy results in significantly lower cardiovascular risk and all-cause mortality. These data further emphasize the importance of promoting cost-effective measures to increase medication adherence in patients on anti-hypertensive treatment.