Adherence to pharmacotherapy for secondary prevention of coronary heart disease: A registry-based prospective study

BACKGROUND AND OBJECTIVE: There is limited data on secondary prevention medications following acute coronary syndrome (ACS) in India. We performed a registry-based study to evaluate adherence to recommended medications following ACS hospitalisation. METHODS: Consecutive patients admitted with ACS were recruited. Data on demographics, baseline characteristics, in-hospital interventions, and prescribed secondary prevention therapies (antiplatelets, statins, beta-blockers, angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), and calcium channel blockers (CCB) at discharge were recorded. 6-months follow-up was conducted to evaluate adherence using validated tools. RESULTS: 716 patients were recruited; the mean age was 60.4 ± 11 years, percutaneous coronary angioplasty (PCI) was performed in 714 (99.7 %) and bypass surgery in none. At hospital discharge, the cardioprotective medications were: aspirin 97.3 %, dual antiplatelets 99.7 %, statins 99.7 %, beta-blockers 74.2 %, ACEI/ARB 38.8 % and CCB 10.9 %. Follow-up data were available for 554 patients; 15 (2.1 %) died and 147 (20.5 %) were lost to follow-up. Medication status and change at 6 months was aspirin 83.9 % (-15.9 %); dual antiplatelets 70.2 % (-29.5 %), statins 70.0 % (-29.8 %), beta-blockers 50.4 % (-32.1 %), ACEI/ARB 22.4 % (-42.3 %) and CCB (-36.7 %) (p < 0.05). Use of high-intensity statins declined from 92.0 % to 45.7 % (-50.3 %). At follow-up, good adherence (>80 %) was 42.7 %, low adherence 24.4 % and non-adherence 10.2 %. Patients with government-sponsored insurance had better adherence than privately insured and self-paying. CONCLUSIONS: Following acute coronary syndrome and PCI, the adherence to prescribed pharmacotherapy is sub-optimal at 6 months with a decline in various medications of 16-42 %. Strategies to increase adherence to secondary prevention therapies are required.