Drug Utilization Study of Antidiabetic Drugs in Patients Attending Geriatric Outpatient Department in Tertiary Care Hospital

Introduction Diabetes has increased in prevalence from 108 million individuals in 1980 to 463 million individuals in 2021. As people's life expectancies have risen, it's become increasingly necessary to be worried about diseases that affect the elderly. To focus and manage these diseases effectively, the illumination of current knowledge about the pattern of anti-diabetic drug utilization in the elderly is important. As a result, it is necessary to evaluate the pattern of anti-diabetic medication use among diabetes patients of the geriatric age group and determine if there is room for improvement in light of current knowledge. With this information, we intend to provide feedback and suggestions for the health care providers. This research aimed to study and analyze the drug utilization of antidiabetic medications in patients attending the geriatric outpatient department. Methods The data of 600 patients visiting the geriatric outpatient department from january 1, 2016 to September 30, 2017 were collected from the electronic medical record (EMR) database. The protocol was designed using Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. Subjects were grouped according to gender, age, drug combination use, and underlying co-morbidities. Indicators of drug usage and the total number of drugs prescribed and prescription patterns were analyzed. Then, the recorded data were classified according to the anatomical therapeutic chemical (AFC) - daily defined dose (DDD) classification. Prescribed daily dose (PDD) values and PDD/DDD ratio of antidiabetic drugs prescribed to a sample of patients (n=600) were calculated. Cost analysis of the prescribed drugs was analyzed and the cost index for each drug is described. Results A total of 600 diabetic patients (286 males) were recruited in the study. In the study, the average age of participants was 69.30 +/- 11.34 years. The most common comorbidity associated with diabetes mellitus (DM) was hypertension followed by hypertension along with chronic heart disease. Glibenclamide and pioglitazone (thiazolidenediones) had PDD/DDD ratio equal to 1. The ratios for glimepiride (sulfonylurea), metformin (biguanides), sitagliptin (sodium-glucose cotransporter 2 inhibitor), insulin glargine, insulin lispro, insulin aspart, were 1.85, 1.29, 1.66, 1.63, 1.42, and 1.21, respectively, whereas the premixed insulin had a ratio of 0.83. The average cost per prescription was USD 3.36 and around 87.72% of the cost per prescription was due to the prescribed antidiabetics. Metformin glibenclamide was the most commonly prescribed combination followed by metformin + glimepiride. Conclusion On the whole, the principles of rational prescription were followed in accordance with the different WHO drug usage indicators. Many of the drugs prescribed by generic name were supplied from hospital pharmacy thus reducing the burden to some extent.