Metformin Still Underused in Type 2 Diabetes Patients

Treating type 2 diabetes with drugs and biologics that are most likely to be effective should be a health care priority.

All evidence points to metformin as the first-line oral diabetes treatment for patients with type 2 diabetes, but research indicates that clinicians often fail to prescribe it when indicated.

A team of pharmacy researchers from Ohio recently looked at metformin, its use, and the reasons clinicians fail to initiate it in a study published ahead-of-print in Pharmacotherapy. They used data from the National Ambulatory Medical Care Survey and conducted a national cross-sectional study of adults with type 2 diabetes, though patients with chronic renal failure or heart failure were excluded because metformin is usually avoided in these patients.

Participating patients made 2348 visits to prescribers, which extrapolates to nearly 89 million visits nationwide.

Previous studies that looked at metformin use reported rates of 51% to 57.8% in fully-insured patients with diabetes. In this study, which looked at overall metformin use, prescribers continued or initiated metformin at roughly 41% of visits—a rate the researchers indicated was unacceptably low. Other studies have found baseline prescribing rates closer to 60%.

Patients who were least likely to receive metformin were those who used insulin, had 4 or more chronic conditions, were Medicare beneficiaries, or saw a medical or surgical specialist.

Meanwhile, patients who identified as Hispanic were most likely to receive metformin.

The researchers indicated that Hispanic patients tend to develop diabetes earlier and have higher rates of obesity at diagnosis, but the population of Hispanic patients in this sample was neither significantly younger, nor more overweight than the overall population. Prescribers may use more metformin in this population because they perceive that it’s weight-neutral.

As the number of diabetic complications increased, the likelihood that the patient received metformin decreased.

The study authors noted that insulin therapy shouldn’t preclude metformin use. When prescribed early, metformin has been proven to decrease the need for insulin and may ameliorate some of insulin’s adverse effects.