267Cardiovascular preventive pharmacotherapy stratified by cardiovascular risk in a complete New Zealand primary prevention population

Abstract

Abstract Background Many countries, including Aotearoa/New Zealand, have guidelines recommending cardiovascular disease (CVD) management based on predicted risk. We conducted the first study to examine CVD preventive pharmacotherapy, stratified by CVD risk, within a complete national primary prevention population. Methods Anonymised individual-level linkage of New Zealand administrative health and non-health data identified 2,250,201 individuals without atherosclerotic CVD, alive and aged 30-74 years on 31/03/2013. We identified individuals with ≥1 dispensing by community pharmacies of blood pressure lowering (BPL) and/or lipid lowering (LL) medications at baseline (1/10/2012-31/3/2013) and in 6-month periods between 1/04/2013-31/03/2016. Individuals were stratified by 5-year CVD risk. Results One quarter of individuals had ≥5% 5-year risk (current New Zealand guideline threshold for considering preventive medications) and 5% met the ≥15% risk threshold for recommended dual therapy. Baseline dual therapy varied according to 5-year risk: 1% with <5%, 15% with 5-9%, 31% with 10-14% and 47% with ≥15% risk. Among those dispensed baseline dual therapy, 83%-89% across risk strata were still treated after three years. Initiation of dual therapy during follow-up occurred among only 13% of high-risk individuals; people without diabetes and those aged ≥65 years were more likely to remain untreated. There were few differences in treatment maintenance across clinical/demographic sub-groups. Conclusions CVD primary preventive pharmacotherapy was strongly associated with CVD risk and, once commenced, was generally continued. However, only half of high-risk individuals received recommended dual therapy and treatment initiation was modest. Key messages Individually-linked administrative datasets can identify clinically-relevant quality improvement opportunities for an entire national population.