Adherence to medication and its determinants among participants of a financial assistance program

• Autor(a) principal: Ramalho, José Pedro Ribeiro
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/162891
• topic: Medication Adherence; Out-of-Pocket Costs; Financial Assistance Program; Social Determinants of Health; Survival Analysis; Adesão à Medicação; Custos Diretos; Programa de Assistência Financeira; Determinantes Sociais de Saúde; Análise de Sobrevivência; Domínio/Área Científica::Ciências Sociais::Outras Ciências Sociais

ABSTRACT - Introduction Ageing populations with an increasing burden of disease and rapidly rising medication costs are features of current healthcare systems which pose serious questions about their sustainability. While access and adherence to prescribed medication are important determinants of health outcomes, they are at risk due to high out-of-pocket medication costs. This work analyses medication adherence and its factors among patients on oral chronic medications (anticoagulants, antidiabetics and antihyperlipidemics) enrolled in a financial assistance program. Methods Adherence to medication was assessed for each drug group using pharmacy dispensing records. We computed Continuous Multiple Interval Measures of Medication Acquisition (CMA) and Gaps (CMG) to assess adherence and employed negative binomial mixed effects models to explore its factors. Discontinuation of medication was evaluated through survival analysis and mixed effects Cox models were used to analyse its determinants. A univariate sensitivity analysis was conducted. Findings A total of 6508 patients fulfilled the inclusion criteria. The global CMA and CMG mean rates were 84.67% (84.25-85.10) and 13.02% (12.68-13.36), respectively. Antihyperlipidemics had the highest adherence rates and antidiabetics had the lowest. Survival analysis showed that 82.94% (82.17-83.72) of patients were still on medication after 6 months, and 60.80% (59.60-62.03) persisted at 12 months, with antidiabetics being the drug class more likely to be discontinued while anticoagulant medication the least likely to. Discussion Adherence in this program was among the highest measured in Portugal and further supports the idea that reducing out-of-pocket medication costs might improve adherence across chronic drug classes, ultimately contributing to positive clinical outcomes and reducing health inequities.