Real-world outcomes of US employees with type 2 diabetes mellitus treated with insulin glargine or neutral protamine Hagedorn insulin: a comparative retrospective database study

Objectives To compare real-world outcomes of initiating insulin glargine (GLA) versus neutral protamine Hagedorn (NPH) insulin among employees with type 2 diabetes mellitus (T2DM) who had both employer-sponsored health insurance and short-tem-disability coverages. Design Retrospective cohort study. Setting MarketScan Commercial Claims and Encounters/Health and Productivity Management Databases 2003-2009. Participants Adult employees with T2DM who were previously treated with oral antidiabetic drugs and/or glucagon-like-peptide 1 receptor agonists and initiated GLA or NPH were included if they were continuously enrolled in healthcare and short-term-disability coverages for 3months before (baseline) and 1year after (follow-up) initiation. Treatment selection bias was addressed by 2:1 propensity score matching. Sensitivity analyses were conducted using different matching ratios. Primary and secondary outcome measures Outcomes during 1-year follow-up were measured and compared: insulin treatment persistence and adherence; hypoglycaemia rates and daily average consumption of insulin; total and diabetes-specific healthcare resource utilisation and costs and loss in productivity, as measured by short-term disability, and the associated costs. Results A total of 534 patients were matched and analysed (GLA: 356; NPH 178) with no significant differences in baseline characteristics. GLA patients were more persistent and adherent (both p<0.05), had lower rates of hospitalisation (23% vs 31.4%; p=0.036) and endocrinologist visits (19.1% vs 26.9%; p=0.038), similar hypoglycaemia rates (both 4.4%; p=1.0), higher diabetes drug costs ($2031 vs $1522; p<0.001), but similar total healthcare costs ($14550 vs $16093; p=0.448) and total diabetes-related healthcare costs ($4686 vs $5604; p=0.416). Short-term disability days and costs were numerically lower in the GLA cohort (16.0 vs 24.5days; p=0.086 and $2824 vs $4363; p=0.081, respectively). Sensitivity analyses yielded similar findings. Conclusions Insulin GLA results in better persistence and adherence, compared with NPH insulin, with no overall cost disadvantages. Better persistence and adherence may lead to long-term health benefits for employees with T2DM.