Out-of-Pocket Costs for Chronic Illness Management in High-Deductible Health Plans.

Importance: High-deductible health plans (HDHPs) enroll a substantial share of privately insured Americans and are associated with reduced use of care, even care that is considered medically necessary. However, the magnitude of patient out-of-pocket (OOP) costs required to obtain evidence-based medical care when enrolled in HDHPs remains poorly understood. Objective: To estimate patient OOP costs required to receive guideline-concordant care for common chronic conditions when enrolled in an HDHP vs a non-HDHP. Design, Setting, and Participants: This retrospective cohort study used 2022 to 2023 national commercial insurance claims data. Participants included adults aged 18 to 64 years with employer-sponsored insurance and previously diagnosed diabetes, hypertension, or both. To enter the cohort, persons had to have received guideline-concordant care for their chronic illnesses. Data were analyzed from July 2025 to April 2026. Exposure: Enrollment in an HDHP vs a non-HDHP. Main Outcomes and Measures: The primary outcome was annual patient OOP costs to receive evidence-based care. Entropy balancing and generalized linear models with geographic fixed effects estimated the mean OOP costs of receiving minimum recommended medical care for diabetes, hypertension, or both in HDHPs and non-HDHPs. Estimates were weighted to ensure that observed costs were representative of the full sample of chronically ill persons. Results: There were 539 590 adults receiving guideline-concordant care who entered the cohort. After entropy balancing, groups exhibited mean covariate balance, with males representing 57.9% of HDHP enrollees and 57.8% of non-HDHP enrollees, and similar age distributions across groups, with 45.4% of both HDHP and non-HDHP enrollees 55 to 64 years of age. The estimated annual OOP cost for individuals to receive guideline-concordant diabetes care was $153.91 (95% CI, $150.18-$157.64) in HDHPs vs $68.06 (95% CI, $66.34-$69.78) in non-HDHPs; $128.94 (95% CI, $127.25-$130.64) in HDHPs vs $53.89 (95% CI, $53.20-$54.58) in non-HDHPs for guideline-concordant hypertension care; and $164.18 (95% CI, $160.93-$167.44) in HDHPs vs $100.60 (95% CI, $98.80-$102.39) in non-HDHPs for guideline-concordant care for comorbid diabetes and hypertension (all P < .001). Conclusions and Relevance: In this cohort study of a large, national sample of chronically ill adults with hypertension, diabetes, or both, annual patient costs were 1.6 to 2.4 times as high to receive recommended care in HDHPs vs non-HDHPs, although the magnitude of the difference in OOP costs was relatively small (range, $63.68 to $85.85). Findings provide novel evidence quantifying the magnitude of cost burden experienced by chronically ill patients under various insurance mechanisms and complement prior HDHP studies evaluating health care utilization.