RESUMO
BACKGROUND: Medication noncompliance has a harmful impact on reaching therapeutic goals of delaying the progression of chronic kidney disease (CKD). The aim of the present study is to calculate the prevalence of medication noncompliance and to identify medication noncompliance-associated factors in CKD. METHODS: A cross-sectional study was performed with 130 CKD patients from a university nephrology outpatient clinic, mean age 48.8 +/- 15.8 years, who were continuously self-administering an antihypertensive or immunosuppressive drug, and who were neither on dialysis nor had received a kidney transplant. Noncompliance was measured through self-report (during an interview) and physician assessment. Patients were considered noncompliers if noncompliance had been detected by any of these methods. Sociodemographic, clinical and laboratory and medication characteristics were surveyed, as well as patients' knowledge regarding prescribed medicines and opinions of the quality of the health care service provided. RESULTS: Prevalence of medication noncompliance was 36.9% (95% confidence interval [95% CI], 28.6%-45.8%). Lack of access to medicines was the most commonly reported problem with medication use (62.5%). Multiple logistic regression analysis showed that patients' insufficient knowledge regarding prescribed medicines (p=0.040) and bad opinions of the quality of the provided health care service (p=0.027) were independently associated with noncompliance. CONCLUSIONS: Medication noncompliance prevalence was high among the patients studied. Lack of access to medicines remains an important public health problem. The noncompliance-associated factors identified in CKD were the patients' poor knowledge regarding the pharmacotherapy and dissatisfaction with the health care service provided.