H-2 META-ANALYSIS OF REAL-WORLD STUDIES OF INITIATING INSULIN GLARGINE VIA DISPOSABLE PEN VERSUS VIAL/SYRINGE AMONG PATIENTS WITH TYPE 2 DIABETES: APPLYING A COMMON DATA STRUCTURE TO A UNIQUE EVIDENCE SYNTHESIS PLATFORM

Friday, October 19, 2012: 1:15 PM
Regency Ballroom C (Hyatt Regency)
Health Services, and Policy Research (HSP)

W. Wei, PhD, MS, MBA1, J. Frimpter1, K. Edwardson2, D. Mitchell1 and MG Savella2, (1)Sanofi US, Bridgewater, NJ, (2)Doctor Evidence, LLC, Santa Monica, CA

Purpose: To synthesize real-world evidence on outcomes among patients with type 2 diabetes mellitus (T2DM) who initiated insulin glargine via disposable pen versus vial/syringe.

Method: We performed a meta-analysis of previously reported retrospective studies conducted in 4 different databases with a common data structure framework (consistently defined study design and measures). All four studies included adult T2DM patients previously treated with oral anti-diabetes drugs and/or glucagon-like peptide-1 therapy only, who initiated insulin glargine via disposable pen (GLA-P) or vial/syringe (GLA-V) between 2007 and 2009. All patients had to have continuous health plan enrollment 6 months prior to insulin initiation (baseline), and 12 months after (follow-up). In each study, baseline differences between GLA-P and GLA-V patients were balanced using stringent 1:1 propensity score matching. Study measures defined consistently across all four studies included 1-year follow-up treatment persistence and adherence, healthcare utilization, and hypoglycemia events. Data was analyzed with random effects modeling, using a unique evidence synthesis platform (Doctor Evidence®, Santa Monica, CA), with I2 to indicate degree of heterogeneity across studies.

Result: A total of 22,234 patients were pooled, and baseline characteristics for GLA-P (N=11,117) and GLA-V (N=11,117) patients were similar across each individual study. During 1 year follow-up, GLA-P patients were 25% more likely to be persistent (39.5% vs. 31.5%, p<0.0001, relative risk (RR) = 1.25, 95% Confidence Interval (CI) 1.15-1.37, I2 = 85.7%) and adherent (mean difference = 0.04, 95% CI 0.03-0.05; I2 = 10.24%), averaging an additional 30.3 days on treatment (95% CI 21.64-38.99; I2 = 81.8%). GLA-P patients were also 24% less likely to have hypoglycemic events (6.4% vs 8.5%; RR=0.76, 95% CI 0.69-0.83; I2 = 0%) and 15% less likely to have hospital visits (21.7% vs 25.7%; RR=0.85, 95% CI 0.81-0.89; I2 = 22.61%), but 26% more likely to have endocrinologist visits (22% vs. 17%, RR=1.26, 95% CI 1.1-1.45; I2 = 83.76%). Heterogeneity varied across analyses. Sensitivity analyses yielded consistent results with the primary analysis.

Conclusion: This meta-analysis supports previous findings from individual studies, suggesting improved outcomes associated with disposable pen versus vial/syringe for T2DM patients initiating insulin glargine therapy. Additionally, application of a common data structure across studies, combined with the unique evidence synthesis platform, enables reliable pooling of retrospective database studies and facilitates synthesis of real-world evidence.