Assessment of the prescribing patterns of lipid lowering drugs at the adult university teaching hospital in Lusaka Zambia

Abstract

Background: Appropriate drug utilization has a huge contribution to global reduction in morbidity and mortality. While thousands of patients have been wrongly prescribed statins, others at high risk of cardiovascular accidents (CVA) have been deprived of treatment. According to the Adult Treatment Panel fourth guidelines (ATP IV), prescription of Lipid Lowering Drugs (LLDs) should not only be based on cholesterol but also on other Atherosclerotic Cardiovascular Disease (ASCVD) risk factors. Methods: A cross sectional design was applied to 140 files of patients at clinic 5 (medical clinic) of the Adult University Teaching Hospital (Adult UTH) and it aimed to determine whether the prescribing patterns of LLDs were in conformity with the ATP IV guidelines. This sample size was based on a 10% (0.1) estimated prevalence of prescriptions containing LLDs in line with the 2014 WHO country profile on Non-communicable diseases (NCDs) which accounted for 23% death estimates in Zambia out of which 8% were due to CVDs. Based on prescriptions given, files of patients for whom LLDs were prescribed were identified out of which study samples were randomly selected. IBM SPSS version 21.0 was used for statistical analyses. Results: There were 89(63.6%) female and 51(36.4%) male patient’s files reviewed. Hypertension (HTN) was the most frequent risk 126(90%) while CVDs were the most common diagnosis category 93(66%). Among the 140 patients whose files were reviewed, 64(45.5%) were found to be eligible for the LLD therapy while 76(54.3%) were not though the difference was not statistically significant (p-value = 0.31). The most commonly prescribed LLD was atorvastatin 20mg 91(65%) while rosuvastatin 20mg and omega-3 were the least prescribed each representing 1 patient (0.7 %). All 64 eligible patients were prescribed atorvastatin out of whom 10(15.6%) received appropriate dosing while 54(84.4%) received inappropriate dosing (Statistically significant: p-value < 0.001). The chi-square exact test results showed that only diagnosis category and prescribed LLDs were significantly associated with dosing appropriateness among the categorical variables (P-values = 0.02 and < 0.001 respectively) while for continuous variables, lipogram duration was significantly associated with dosing appropriateness(P-value <0.001). The unadjusted odds ratios (OR) showed that patients with CVD diagnosis had on average 13 times increased odds for inappropriate dosing (OR = 13.2, CI = 1.76 – 98.93, p-value = 0.01). Conclusion: This study suggests that the prescribing patterns were not in conformity with the ATP IV guidelines as they were more inclined to individual CVD risk factors and not the individual patients’ overall levels of risk. Key words: Assessment, Prescribing Patterns, Lipid Lowering Drugs