Factors Associated with Severe Hypoglycemia among Patients with Type 2 Diabetes Treated with Insulin

We have previously reported that rates of severe hypoglycemic events (SHEs, defined as events that required hospitalization or an emergency department visit) are higher in patients with type 2 diabetes (T2D) on insulin alone (3.4%) or insulin+SU (2.5%) compared to those on insulin+other anti-hyperglycemic agents (AHA) (1.6%). The present analyses were conducted to further evaluate the independent risk factors of SHE after accounting for differences in two treatment groups based on propensity for SHE: Insulin±SU and Insulin+Other AHA. This retrospective analysis using MarketScan database included T2D adults (n=202,147; mean age: 54.0 years; 53% females) with a first prescription of insulin from 1/1/2013 to 12/31/2013 (index period). SHE was measured from the index date to the end of follow-up (12/31/2013). Multivariable Poisson regression was performed to compare the risk of SHE between insulin±SU vs. insulin+other AHA users and assess other predictors. The unadjusted SHE rate per 100 person years was 2.2% among all patients; 2.8% among those on insulin±SU and 1.3% among those on insulin+other AHA. After adjusting for patient’s baseline characteristics, the risk of SHE was 84% higher in patients on insulin±SU compared to those on insulin+other AHA [Hazard ratio (HR):1.84; 95% confidence interval (CI): 1.68- 2.01]. In addition to the treatment type, other factors predictive of SHE were previous history of SHE (HR: 4.73; 95% CI: 4.33- 5.17); and history of comorbidities including chronic kidney disease (HR: 1.75; 95% CI: 1.60-1.92), cardiovascular disease (HR: 1.60; 95% CI: 1.46-1.75), and neuropathy (HR: 1.55; 95% CI: 1.43-1.69). Our results suggest the risk of SHE is lower in patients on insulin with other AHA compared to patients on insulin alone or with SU. Healthcare professionals should take into account the risk of having SHE while making treatment choices especially for vulnerable populations such as patients with prior history of SHE, and other comorbidities.