Resumen de Assessing the Adherence to and the Therapeutic Effectiveness of Hypolipidemic Agents in a Population of Patients in Brazil: a Retrospective Cohort Study

Cássia Cunico, Geraldo Picheth, Cassyano J. Correr, Marileia Scartezini

• Objective: to evaluate the relation between patient adherence and therapeutic effectiveness of hypolipemiant agents in clinical practice.Methods: A retrospective study of 417 patients using hypolipemiant drugs (simvastatin, atorvastatin) between 2003 and 2010 was performed. The study population consisted in patients assisted by the Public Health Service in the far-west region of the State of Santa Catarina, Brazil. The Medication Possession Ratio obtained from pharmacy refill data was used to measure patient adherence. Therapeutic effectiveness was evaluated based on the difference obtained in the serum levels of total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides, before and after taking the drug, in an average time of 8.3 months.  Results: Following the treatment with hypolipemiant agents, it has been observed a reduction of 14.3% for total cholesterol, 19.6% for LDL-cholesterol, and 14.4% for triglycerides. HDL-cholesterol increased by an 8.0% average. Atorvastatin 20 mg daily promoted the major changes in lipid profile. The medication adherence rate decreased over the monitoring period. Rates of compliance below 60% were associated with therapeutic failure, while rates equal to 80% or higher were associated with the best response to the lipid-lowering drugs.Conclusion: Adherence to hypolipemiant agents is higher at the beginning of the treatment, but it decreases over time, affecting the achievement of therapeutic goals. The adoption by the pharmacist of actions to monitoring patient compliance to pharmacy refills can be helpful to identify patient at high risk for therapeutic failure and can potentially improve treatment success.