Direct medical cost associated with antiplatelet non-persistence in acute coronary syndrome patients after percutaneous coronary intervention

Background: Non-persistence of antiplatelet therapy in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) can have consequences in higher economic burden.
Objectives: To investigate the association between persistence to treatment with antiplatelet therapy and direct medical cost in patients presenting with ACS and undergoing PCI.
Methods: This is a retrospective observational study carried out in five hospitals with PCI facilities in Indonesia
between January2019 and February 2020. A patient was defined as having non-persistence to treatment if there was a gap of more than 30 days without a refill for the same medication. Persistency was assessed for platelet aggregation inhibitors (WHO ATC Code: B01AC). Direct medical costs were collected based on the actual cost derived from billing data in outpatient and inpatient units. This includes administration, cost of medication, consumable medical supplies, cost of invasive treatments, laboratory tests, accommodation, doctor consultation, and other health professional consulting services.
Results: A total of 367 patients were recruited. Of these,267 patients had complete billing data available for cost analysis with 202 (75.6%) persistence and 65 (24.4%) non-persistence to antiplatelet therapy. The average cost of medication was IDR3,522,741 (USD 237.54) in the persistence group compared with IDR 5,526,641 (USD 372.71) in the non-persistence group(p = 0.02). Total direct medical cost in the persistence group was significantly smaller than the non-persistence group [IDR10,287,447 (USD 693.77) versus IDR 12,710,256 (USD 857.16);p = 0.02]. The higher total direct medical cost was significantly associated (p< 0.05) with older age (≥ 59 years), being male, being admitted to the hospital with a referral, hospital bills paid by the national health insurance, having a history of cardiovascular dis-eases, hypertension, and diabetes.
Conclusions: This study indicates non-persistence of antiplatelet therapy among ACS patients after PCI was associated with a higher cost of medication and higher total direct medical cost. Higher total direct medical costs for ACS patients after PCI were influenced by their comorbidities, namely hypertension, and diabetes.