Analyzing Antidiabetes Drug Prescriptions With World Health Organization Anatomical Therapeutic Chemical/Defined Daily Dose Index to Assess Drug Utilization Pattern in Elderly Population of Rural Eastern India

Abstract

Objective: To analyze drug utilization (DU) pattern of antidiabetes drug (ADD) prescription in elderly type 2 diabetes mellitus (T2DM) in rural West Bengal based on 2016 World Health Organization (WHO) Anatomical Therapeutic Chemical/Defined Daily Dose (ATC/DDD) Index. Methods: This was a prospective observational study. Prescription data of 600 elderly patients (age > 60 years) attending outpatient clinic were screened over 12 months (January 2015 to January 2016) from 5 different rural hospitals in West Bengal. Pooled data were sorted and classified in accordance with 2016 ATC/DDD WHO Index. Direct cost associated and consumption of ADD were measured as DDD/1000 patients/day. The adverse drug reactions (ADRs) related to antidiabetic medicines were monitored. Results: During the study period, mean age of patients recorded was 66.4 ± 5.0 years, with 66.6% (n = 396) having history of T2DM > 5 years. Follow-up encounters (n = 2328) revealed metformin (94.67%), sulfonylureas (SUs) (50.54%), pioglitazone (24.22%), voglibose (22.50%), insulin (9.75%), and acarbose (6.82%) to be more prevalent, constituting DU 90% (92.01%). Combination of metformin plus SU was recorded in most of the patients (56%). Insulin, however, was found to be an underutilized class (P < .005). The DDD/1000 patients/day of metformin (2.918), glimepiride (1.577), and gliclazide (0.069) conformed to 2016 WHO ATC/DDD Index. The total ADD consumption during study period was 5.03 DDD/1000 patients/day. The average drug cost per encounter per day was Rs 11.24 ± 2.01. Nineteen ADRs were reported and their descriptions were found to be of hypoglycemia (n = 9), pedal edema (n = 2), and gastrointestinal upsets (n = 8). Target glycemic status was achieved in 40% monthly follow-up encounters. Low-store drug availability and poor compliance to treatment (>60%) were major determinants. Lack of regular aerobic exercises (>85%) and proper knowledge regarding medical nutrition therapy (MNT) (>80%) and low average consultation time (3.5 ± 0.6 minutes) were important contributing factors. Conclusions: The study exhibited increased utilization of 2 drug combinations of oral ADD and lower utilization of insulin during study period. Such inferences merit further exploration.