Expenditures in Patients Taking Noninsulin Antidiabetic Agents

San Diego—Healthcare decision makers face challenges in optimizing disease management in patients with type 2 diabetes mellitus (T2DM). Increasing healthcare expenditures can be attributed, in part, to the costs, including medical and pharmaceutical, associated with managing T2DM.

There are various noninsulin treatment options available to patients with T2DM to control hyperglycemia, including metformin, sulfonylureas (SU), thiazolidinediones (TZD), dipeptidyl peptidase-4 inhibitors (DPP-4i), and glucagon-like peptide-1 receptor agonists (GLP-1). Noting that “assessing healthcare expenditures will help payers better understand economic implications of disease burden,” researchers recently designed a retrospective observational cohort study to compare costs associated with utilization of those agents.

They reported study results during a poster session at the AMCP meeting. The poster was titled One-Year Healthcare Expenditures in Type 2 Diabetes Patients Taking Non-Insulin Antidiabetic Agents.

Study participants were patients with T2DM who initiated treatment with SU, TZD, DPP-4i, or GLP-1 between August 1, 2009, and June 30, 2011. The researchers utilized data from Truven Health Analytics MarketScan^® Commercial and Medicare Supplemental Databases from August 1, 2009, through June 30, 2011.

Inclusion criteria included 1 year of continuous medical and pharmacy enrollment prior to and following the first drug prescription claim (index prescription) and at least 1 International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code of T2DM during the year prior to or following the index prescription.

Patients were assigned to 1 of the 4 mutually exclusive drug cohorts using a hierarchal approach. All patients were considered for the saxagliptin (DPP-4i) cohort first. The remaining patients who did not qualify for the saxagliptin cohort were then considered for the GLP-1 cohort and finally for the SU and TZD cohorts. SU and TZD cohorts were assigned at the same time/level depending on which was prescribed first.

There were 3812 patients in the saxagliptin cohort, 7810 in the GLP-1 cohort, 45,604 in the SU cohort, and 22,292 in the TZD cohort. Of the patients in the saxagliptin cohort, 55.6% were male, compared with 42.1% of GLP-1, 56.1% of SU, and 57.4% of TZD patients. Patients in the saxagliptin cohort were significantly older than in the other 3 cohorts. Across all 4 cohorts, preferred provider organizations were more common; the saxagliptin cohort had the lowest percentage of patients with any capitated insurance claims.

The unadjusted analysis of all-cause total expenditures found that expenditures in the TZD and SU cohorts were lower than in the saxagliptin cohort; following adjustment, TZD expenditures were higher than both the SU and saxagliptin cohorts. The saxagliptin cohort had significantly lower adjusted medical expenditures (nonpharmacy) than any other cohort: $5253 versus $5762 (GLP-1), $6071 (SU), and $5534 (TZD).

After adjustment, diabetes-related total expenditures were significantly lower in the SU cohort and significantly higher in the GLP-1 cohort compared with the saxagliptin cohort (P<.05 for both comparisons). Diabetes-related medical (nonpharmacy) expenditures, after adjustment, were significantly lower in the saxagliptin cohort than in any other cohort: $829 versus $961 (GLP-1), $1013 (SU), and $879 (TZD) (P<.05 for all comparisons).

In summary, the researchers said, “In most cases, 1-year healthcare expenditures for saxagliptin were less when compared to the other drug classes…mean medical (nonpharmacy) expenditures and diabetes-related medical (nonpharmacy) expenditures were significantly lower among patients in the saxagliptin cohort compared to the other 3 cohorts.”

This study was supported by Bristol-Myers Squibb and AstraZeneca.