Background: Does initiation of a continuous glucose monitor (CGM) or insulin pump lower health care utilization and/or costs?
Methods: Distinct cohorts of people with type 1 diabetes (T1D) or type 2 diabetes (T2D) using a blood glucose monitor (BGM), CGM, pump, or CGM with pump were identified from a large claims database. Patients ≥40 years old with 12 months of continuous enrollment before and after the device start date qualified for the study. Outcomes included one-year medical utilization and costs (minus device) for events such as hospitalizations and office visits. Generalized linear models were fitted, controlling for numerous baseline covariates. The Holm method corrected for the multiplicity of hypotheses tested.
Results: Of the 8235 total patients, the BGM control group was the largest, had the lowest percentage of patients with T1D, and was significantly different from the device groups in most baseline categories. Formally, only two comparisons were statistically significant: Compared with BGM, the pump cohort had greater adjusted first-year total medical and office visit costs. Other secondary outcomes such as days hospitalized, emergency department visits and labs, favored pump. Most endpoints were favorable for CGM. Results for CGM with pump generally were intermediate between CGM and pump alone.
Conclusions: During a one-year follow-up, unadjusted medical costs of both CGM and pump appear lower than BGM, but multivariable modeling yielded adjusted savings only for CGM use. Economic benefits might be observable sooner for CGMs than for pumps. Generalized linear models fitted to health care utilization event rates produced favorable results for both CGM and pump.
Keywords: continuous glucose monitor; generalized linear model; health economics; insulin pump; medical costs; real-world study.