Body Mass Index and Insulin Use as Identifiers of High-Cost Patients with Type 2 Diabetes: A Retrospective Analysis of Electronic Health Records Linked to Insurance Claims Data.

AIMS: To study the association of body mass index (BMI) and insulin use with type 2 diabetes-related healthcare expenditures (T2D-HE).

MATERIALS AND METHODS: Retrospective study using de-identified electronic health records linked to insurance claims data. Study included a prevalence-based sample of overweight or obese patients with antihyperglycemic-treated T2D. Patients had ≥1 A1c measurement in 2014 (last observed=index A1c), ≥1 BMI measurement within ±90d of index (average BMI=baseline BMI), and continuous enrollment for 180d before (baseline) through 395d after index (day 30-395=follow-up). BMI was categorized as: 25-29.9 kg/m2 =overweight; 30-34.9 kg/m2 =obese class I (OCI); 35-39.9 kg/m2 =OCII; ≥40 kg/m2 =OCIII. Multivariable regressions were used to examine one-year follow-up T2D-HE as a function of BMI, insulin use, an interaction term between BMI and insulin use, and patient demographics.

RESULTS: Study included 13,026 patients (mean age=63.6 years; 48.1% female; 29.5% overweight, 31.6% OCI, 20.3% OCII, 18.6% OCIII; 25.3% insulin users). Baseline insulin use rates monotonically ranged from 19.7% in overweight patients to 33.0% in OCIII patients (p<0.001). Together, BMI and insulin use were jointly associated with one-year follow-up T2D-HE, which monotonically ranged from $5,842 in overweight patients with no insulin to $17,700 OCIII insulin users, p<0.001. Within each BMI category, insulin users' one-year T2D-HE was at least double that of non-users. Additional analyses of all-cause healthcare expenditures yielded consistent results.

CONCLUSIONS: BMI and insulin use represent simple stratifiers for identifying high-cost patients. OCIII insulin users incurred the greatest annual healthcare expenditures; these patients may be an ideal group for targeted interventions. This article is protected by copyright. All rights reserved.