TOPLINE:

A mandated switch from health plans with low deductibles to those with high deductibles was associated with a delay in the diagnosis of diabetes and increased total and out-of-pocket medical costs.

METHODOLOGY:

• In this observational longitudinal study, researchers used administrative claims data from 2003 to 2017 to determine whether switching to a high-deductible health plan affected the timing of diabetes diagnosis and costs around the time of diagnosis.
• Health plans with deductibles of $1000 or more were classified as high deductible, and those with $500 or less as low deductible.
• The analysis included 346,492 adult enrollees without diabetes (mean age, 42 years; 48.5% women) who were switched by their employers; they were matched to an equal number of those concurrently offered only low-deductible plans.
• The primary outcome was the time to first diagnosis of diabetes, comparing rates during the 12 months before and at least 1 month after the index date, which was defined as the date of switch for those on high-deductible plans or the date of annual renewal for those on low-deductible plans.
• Total and out-of-pocket medical costs were analyzed from 30 days before to 90 days after the first diagnosis of diabetes.

TAKEAWAY:

• Being on high-deductible vs low-deductible health plans was associated with a delay in the first diagnosis of diabetes (adjusted hazard ratio [aHR], 0.93; 95% CI, 0.88-0.99), with the median time to diagnosis from the index date being 37.0 months for members on low-deductible plans vs 38.7 months for those on high-deductible plans.
• Women who switched to high-deductible plans experienced delays in the diagnosis of diabetes compared with those who stayed on low-deductible plans (aHR, 0.91; 95% CI, 0.84-0.99) and were diagnosed 2.1 months later when comparing periods before vs after the index date.
• Total medical costs in the peri-diagnosis period increased by 20% among newly diagnosed individuals who were switched to high-deductible plans. Out-of-pocket costs increased by 51%, largely driven by inpatient and observation unit charges.

IN PRACTICE:

“The clinical significance of the 1.7-month median delay that we detected deserves careful consideration. On the one hand, this might seem a relatively short span unlikely to affect patient health. On the other hand, we also found a concerning 20% increase in total peri-diagnosis medical costs among newly diagnosed [high-deductible health plan] members,” the authors of the study wrote.

SOURCE:

This study was led by Felippe Ottoni Marcondes, MD, MPH, of the Division of General Internal Medicine at the Massachusetts General Hospital in Boston. It was published online on August 29, 2025, in the Journal of General Internal Medicine.

LIMITATIONS:

This study was observational. Certain delays may have been related to switching between clinician networks. The researchers could not distinguish between the diagnostic setting for diabetes (outpatient, inpatient, or emergency department).

DISCLOSURES:

This study received grants from the CDC, the National Institutes of Health, and the American Heart Association, among others. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.