The prevalence of and factors associated with inappropriate metformin prescription in type 2 DM patients with contraindications: a case study in Thailand
Keywords:
Metformin, Inappropriate prescription, DiabetesAbstract
Objectives: To explore the prevalence of and factors associated with inappropriate metformin prescription in type 2 DM patients with contraindications.
Design, setting, participants: A cross-sectional study including type 2 DM patients aged ≥30 who visited the outpatient department at Lampang Hospital in 2017 and were prescribed metformin at least once. Data from electronic medical records (EMR) were used to identify diabetic patients using ICD10 codes, together with other covariates. Inappropriate prescription was defined as patients receiving metformin over the maximum daily doses indicated for each of the risks. The risks were categorized into the following 3 groups: 1) Metformin prescription not recommended in patients with CKD stage 4 or above, chronic liver disease, or heart failure; 2) A maximum daily dose of 1,000 mg in patients with CKD stage 3b; and 3) A maximum daily dose of 2,550 mg in patients without the abovementioned conditions.
Outcomes measured: Primary outcome: prevalence of inappropriate metformin prescription in type 2 DM patients with contraindications.
Results: Among 5,812 DM patients, the prevalence of inappropriate metformin prescriptions was 15%. Of these, 8.6% were prescribed metformin over the maximum dose of 2,550 mg per day. In CKD stage 3b group, 46% received inappropriate prescriptions. The specialty of physician and the length of work experience were found to be associated with inappropriate metformin prescription
Conclusion: This study has revealed a high prevalence of inappropriate metformin prescription, indicating a remaining concern that requires further action to reduce the incidence of the drug misuse.
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