Posted Nov 14 , 2017 01:30 AM

Antihyperglycemic Medications: A Claims-Based Estimate of First-Line Therapy Use Before Initialization of Second-Line Medications

Tseng YJ, et al. Diabetes Care 2017 Online ahead of Print

What were the findings (excerpted from the Abstract)?

The American Diabetes Association recommends metformin as first-line therapy for type 2 diabetes. However, nonadherence to antihyperglycemic medication is common, and a clinician could confuse nonadherence with pharmacologic failure, potentially leading to premature prescribing of second-line therapies. We measured metformin use before second-line therapy initiation. This retrospective cross-sectional study used unidentifiable member claims data from individuals covered from 2010 to 2015 by Aetna, a U.S. health benefits company. Beneficiaries with two physician claims or one hospitalization with a type 2 diabetes diagnosis were included. Recommended use of metformin was measured by the proportion of days covered over 60 days. Through sensitivity analysis, we varied estimates of the percentage of beneficiaries who used low-cost generic prescription medication programs. A total of 52,544 individuals with type 2 diabetes were eligible. Of 22,956 patients given second-line treatment, only 1,875 (8.2%) had evidence of recommended use of metformin in the prior 60 days, and 6,441 (28.0%) had no prior claims evidence of having taken metformin. At the top range of sensitivity, only 49.5% patients could have had recommended use. Patients were significantly more likely to be given an additional second-line antihyperglycemic medication or insulin if they were given their initial second-line medication without evidence of recommended use of metformin. Despite published guidelines, second-line therapy often is initiated without evidence of recommended use of first-line therapy. Apparent treatment failures, which may in fact be attributable to nonadherence to guidelines, are common. Processes are needed to monitor and improve guideline adherence.

Why is this important?

Metformin has been around a very long time for the treatment of diabetes, and even for the prevention of diabetes in people with pre-diabetes. It has been recommended as initial therapy for individuals with type 2 diabetes by most major diabetes organizations. One would assume, that the need for so-called ‘second line’ therapy would occur if metformin was failing to deliver glucose control. We know, of course, that medication adherence is a problem with all medications used to treat diabetes. While we make the tacit assumption that the patient is taking metformin when it is prescribed (realizing that adherence is an issue) this analysis points to a little-known issue, namely that often second line medications are given without having evidence of the ‘first-line’ medication being utilized. Adherence is clearly an issue, not only medication adherence with prescribed metformin, but guideline adherence by prescribing it in the first place. Clearly this latter adherence issue is associated with an increased likelihood of additional second line medications or insulin. Metformin is recommended as first-line therapy for a reason. Make sure you have prescribed it (unless there are any contraindications) AND that the patient is taking the medication (preferably at the maximum dose for that individual) before moving to second line agents. It will keep the overall costs low, and maximize the benefit of the medication. Do you prescribe metformin for your patients newly diagnosed with type 2 diabetes? Do you assess if the patient is adhering to the doses prescribed before adding a second-line medication?

Read the Abstract: