Why Is Metformin Underused as a First-Line Diabetes Treatment?

Current guidelines for type 2 diabetes (T2D) management recommend metformin as the first-line medication. It is the only oral diabetes medication that consistently reduces cardiovascular morbidity and mortality in clinical studies. Regardless, clinicians prescribe metformin less often than they should, prescribing it to just 65% of newly diagnosed T2D patients. Over time, the number of patients who remain on metformin hovers at 25%.

It is unclear why clinicians shy away from metformin, although a fear of precipitating lactic acidosis in at-risk patients may be one explanation. Researchers from the University of Colorado School of Pharmacy have published a study in Therapeutic Advances in Chronic Disease that examines potential barriers to better uptake.

The researchers assembled focus groups that included providers (physicians, pharmacists, mid-level practitioners) caring for patients with T2D in ambulatory settings. They examined provider attitudes, behaviors, and opinions regarding the use of metformin.

Focus group participants verbalized 3 main themes that may have influenced their prescribing:

· Appropriate timing of metformin initiation

· Known risks associated with metformin

· Procedures to manage safety concerns and mitigate adverse effects associated with metformin

The researchers found that participants' perceptions of metformin were inconsistent with current evidence, and their erroneous perceptions influenced prescribing. In particular, participants were out-of-date with best available evidence in regard to renal insufficiency, heart failure, hepatic dysfunction, alcohol use, and lactic acidosis.

Minimal educational interventions, such as discussion of evidence with the group, effectively changed some participants' attitudes. The authors suggested several ways that health care systems can change providers' attitudes in the real world:

· Traditional educational sessions describing metformin's benefits and risks in special populations

· Implementation of point-of-prescribing electronic clinical decision support tools

· Use of clinical decision support interventions within electronic medical records

· Integration of clinical decision support tools that summarize and present clinical information efficiently and well into the workplace

The authors encourage educators to target prescribing behaviors that are inconsistent with evidence.