Health care costs associated with treatment modification in type 2 diabetes mellitus patients taking oral anti-diabetic drugs

Abstract

Objectives: To compare health care costs among patients with type 2 diabetes mellitus (T2DM) who added a new oral anti-diabetes drug (OAD) to an initial regimen with those who up-titrated their initial OAD.

Methods: Insurance claims data were obtained from 94 health plans for patients aged ≥18 years with ICD-9-CM diagnosis of T2DM during the period Jan. 1, 2001-June 30, 2007, and a newly prescribed metformin or sulfonylurea monotherapy. Patients were followed after initiating monotherapy to identify occurrence of first-treatment modification (addition or up-titration). Health care costs were analyzed during 360 days after first treatment modification. Subgroup analyses included comparison of addition cohort with two titration subgroups: 1) titration up to or below intermediate doses and 2) titration to beyond intermediate doses.

Results: During the post-treatment modification period, all-cause medication costs were 9% higher (p < 0.0001), while inpatient costs were 14% lower for the addition cohort (p < 0.008) as compared to the up-titration cohort. The total risk-adjusted health care costs were slightly lower but statistically insignificant for the addition cohort compared to the up-titration cohort (ratio of cost = 0.99; p = 0.052). These costs patterns remained similar for both the up-titration subgroups.

Conclusions: While addition of another OAD to the initial OAD regimen may result in higher medication costs, the lower inpatient costs and overall offset in the subsequent total costs may indicate clinical benefits with the add-on treatment. When appropriate and clinically beneficial, physicians may want to consider adding an OAD rather than up-titrating the current OAD, particularly beyond intermediate dose levels.