Recent antihyperglycemic prescribing trends for US privately insured patients with type 2 diabetes

The mid-1990s witnessed the introduction of new classes of medications to treat hyperglycemia of type 2 diabetes. There is evidence that these newer classes have found a place in the therapeutic armamentarium, but details of their use patterns are not known. We sought to determine whether antihyperglycemic prescribing patterns changed concurrently with new drug introductions, and whether such changes were related to changes in the underlying patient population.

A sample of U.S. privately insured patients with suspected type 2 diabetes was identified from the MarketScan Research Database over the period of 1997-2000. Patients with type 2 diabetes were identified among those continuously enrolled in the database for at least 1 year. Drug therapy episodes were defined by sequential fulfillment of prescriptions implying a continuous supply of a particular drug (or combination) of at least 30 days duration. Univariate analyses were used to explore trends over time in drug prescriptions and patient characteristics. Multivariate logistic regressions were used to isolate the impact of year from other variables on the likelihood of receiving prescriptions for a specific therapy.

A total of 232,020 unique diabetic patients had an average of 1.91 diabetes drug therapy episodes between 1997 and 2000. Monotherapy with sulfonylureas decreased, but monotherapy with thiazolidinedione, metformin, and other oral antihyperglycemics increased over time. Combinations of sulfonylureas and metformin; sulfonylureas and thiazolidinedione; metformin and thiazolidinedione; and sulfonylureas, metformin, and thiazolidinedione each increased over the time interval. Insulin monotherapy decreased, as did insulin combination therapy with sulfonylureas. The combination of insulin and metformin increased, whereas insulin and thiazolidinedione was stable. The influence of year on prescribing patterns remained highly significant (P < 0.001) after adjusting for patient characteristics.

Antihyperglycemic prescription patterns in the U.S. have changed in recent years in parallel with, and probably as a direct result of, the introduction of different classes of medications to the marketplace. Overall, the prescribing trend has been away from monotherapy with insulins and sulfonylureas and toward combination therapies, presumably in attempts to reduce hypoglycemic symptoms and to achieve better glucose control.