Uso de estatinas nos Sistemas Públicos de Saúde do Brasil e da Escócia: achados e implicações

Abstract

Statins have become an integral part of treatment to reduce cardiac events in patients with cardiovascular disease. Population-based studies on statins use are still scarce, with the main evidence from randomized clinical trials. Knowledge of the use of medicines in the real world is essential for improving health care and public policies. This study aims to characterize the polypharmacy in the primary health care patients of the Unified Health System (SUS) and to identify its associated factors; to characterize statin use in SUS and evaluate associated patient factors; and to evaluate adherence, discontinuation, and persistence of statins in Scotland. It was performed a cross-sectional study in Brazil, with a national representative sample from five regions, using a multi-stage complex sampling plan. The variables of interest were polypharmacy (use of 5 drugs) and use of statin. Patients over 18 years old were interviewed from 2014 July to 2015 May. The associations between statin use, polypharmacy and covariables were assessed using logistic regression. It was also performand a retrospective cohort study using linked data from the National Health System of Scotland, including adult patients who initiated statin from 2010 January to 2016 December. Statin treatment was stratified into high intensity, moderate intensity, and low intensity, based on the National Institute of Health and Care Excellence (NICE) classifications. Treatment discontinuation and persistence were evaluated using the 60 days-refill-gap and anniversary methods, respectively; adherence was defined as PDC (proportion of day covered) 80%. In Brazil, a total of 8,803 patients were interviewed, of whom 6,511 were medicine users. The prevalence of polypharmacy was 9.4% in the general population and 18.1% in the elderly (65 years old). There was a statistically association between polypharmacy and age >45, presence of chronic diseases, have health insurance, and regions of Brazil. The prevalence of statin use was 9.4% with simvastatin (90.3%) and atorvastatin (4.7%) being the most used. Statin use was significantly associated with age, educational level, alcohol consumption and polypharmacy. In Scotland, a total of 73,716 patients (mean age 62±12.6) initiated statin therapy: high intensity (9.7%), moderate intensity (88.3%), low intensity (1.9%). Discontinuation rates differed significantly between intensity levels (50,9% in high intensity vs. 75,5% in low intensity). Adherence and persistence were highest among high-intensity patients. This is the first population based study in Brazil to assess statin use in SUS primary healthcare settings. Polypharmacy is a reality and may be related to inappropriate use of drugs. Addressing inequalities in access and use of medicines is an important step in achieving the full benefit of statins in Brazil. In Scotland, adherence and persistence to statin therapy remain a challenge. However, increasing the intensity of statin therapy does not seem to negatively impact adherence and persistence to treatment.