Abstract Body (Do not enter title and authors here): Background: An evaluation of the longitudinal burden of healthcare expenses in type-2 diabetes mellitus (T2DM) is limited to self-selected cohorts and claims-based or self-reported spending. Leveraging the 21^st Century Cures Act rule that made reporting hospital-level service prices mandatory, we demonstrate healthcare spending in T2DM with and without cardiovascular disease in a diverse multisite EHR-based T2DM cohort.

Methods: Patients with T2DM seeking regular care (≥ 1 visit/2 years) across 5 hospitals and a large outpatient network (2013-2023) in the Yale New Haven Health System (YNHHS). Cohorts were defined by the presence of atherosclerotic cardiovascular disease (ASCVD) and/or heart failure (HF) before or up to 1 year after the T2DM diagnosis. We used the YNHHS chargemaster file to extract Medicare and insurance-negotiated cash prices. We linked census data using residential zip codes to estimate household income, used multivariable logistic regression to identify factors associated with financial hardship (health expenses >20% of income), and evaluated expenses during the last year of life. All values were inflation-adjusted to 2023 US$.

Results: Overall, 106881 patients with T2DM followed for 5.4 years (3.1-7.5) had 147919 hospitalizations, representing $3.41B in expected healthcare expenses. 8% of patients with T2DM without ASCVD/HF, 14% with ASCVD, 23% with HF, and 28% with ASCVD and HF had a financial obligation for healthcare above the threshold for financial hardship. Compared with White patients, Black and Hispanic patients were more likely, and Asians were less likely to have financial hardship (OR: Black, 1.81 [1.73-1.91]; Hispanic, 1.39 [1.31-1.48]; Asian, 0.46 [0.37-0.57]), after accounting for age, sex, and comorbidities. Comorbid HF at baseline portended 2x higher odds of financial hardship (OR: HF, 2.20 [2.00-2.42]; ASCVD and HF, 1.98 [1.84-2.14]) compared with T2DM alone. Care in the last year of life represented 72-80% of overall health expenses, with 55-61% of patients at risk for financial hardship across cohorts.

Conclusion: A digital individualized expense-linked registry of patients enabled by recent US price transparency rules defined that annually, one-fifth of patients with T2DM and cardiovascular disease had healthcare events exceeding 20% of their annual income, and vulnerable racial/ethnic minorities were at high risk for financial toxicity.