Predictors and patterns of polypharmacy in chronic diseases in a middle-income country

Low and middle-income countries (LMIC) are increasingly affected by non-communicable diseases (NCDs), which overburden the health system. With the rising prevalence of multimorbidity, polypharmacy is inevitable. Sri Lanka too faces the burden of polypharmacy and multimorbidity, and it is a strain on the economy as Sri Lankan health care is free-of-charge to all citizens. Therefore, steps to reduce inappropriate polypharmacy are a necessity. The aim of the study was to assess the prevalence and patterns of polypharmacy and its associated factors. In the medical clinics of a tertiary care hospital and a University primary care department, a descriptive cross-sectional study was carried out. Data were extracted from the clinical records of patients over the age of 20 years with a minimum of one NCD diagnosed by either a consultant physician or a consultant family physician. The sample size was 1600. Multimorbidity was present among 63.5% of patients. Polypharmacy (five or more than five drugs) was seen in 36.8% of the patients. Diabetes, hypertension, and coronary heart disease were the commonest of all diseases. Those on more than 11 drugs were found to have diabetes mellitus, hypertension, coronary heart disease, chronic kidney disease, and cardiac failure. 15% of the patients in the primary care setting and 59% of the patients in tertiary care experienced polypharmacy. Multiple regression analysis confirmed that polypharmacy increased with male gender, advancing age, and the degree of multimorbidity. Horizontal and vertical integration of multidisciplinary teams in all disciplines to manage patients is needed to combat inappropriate polypharmacy. This will help in optimizing the management of patients with NCDs.