"Policymakers working to improve the affordability of care should focus on innovative approaches to cost-sharing that prevent dramatic financial shocks to household budgets due to medical bills."

Annual metrics ignore important variations in the distribution of spending throughout the year, the report said, which could result in affordability challenges for the large number of Americans who lack savings to cover large and unexpected expenses. Despite the well-documented financial challenges that many households face in terms of rising debt and stagnant wages, temporal clustering of out-of-pocket spending remains an understudied aspect of health-care affordability.

Researchers uncovered several statistics that could shape changes to the current system:

• Commercial insurance enrollees interacted with the health-care system through an office visit, inpatient stay or filling a prescription on 13 distinct days throughout the year on average.
• An estimated 11% of enrollees had no health-care encounters. An additional 6% of enrollees had at least one encounter but no cost-sharing. The remaining 83% of enrollees were responsible for a portion of their health-care costs. For them, the average annual cost-sharing was $954.
• Nearly 40% of commercially insured people incurred half of their annual out-of-pocket spending in just one encounter, and 26% incurred 90% of their annual out of pocket spending in only one or two encounters.
• This pattern persisted even among people with annual out-of-pocket spending exceeding $400. Among them, 33% incurred half of their annual out-of-pocket spending in just one encounter.
• Among people with low demand for health services, 34% incurred no cost sharing during the year and an additional 44% reached half of their annual out-of-pocket spending in a single day. Among people with high demand for health services, 32% reached half of their annual out-of-pocket spending in a single day, and 13% incurred 90% of that spending within 30 days.
• Although few people reached the in-network out-of-pocket maximum for an individual allowed under the Affordable Care Act ($7,150), 14% of those who reached that amount did so in a single day, and 29% reached that amount within 30 days.
• Of people experiencing any out-of-pocket spending (83% of the sample), 10% incurred some expenses during every calendar month of the year, and 44% incurred expenses during at least six calendar months.

"Many people with employer-sponsored insurance incur substantial out-of-pocket spending within a short time span, leading to potential challenges to affording health care," researchers concluded. "Policymakers working to improve the affordability of care should focus not only on curbing the growth of health-care prices but also on innovative approaches to cost-sharing that prevent dramatic financial shocks to household budgets as a result of medical bills.

"For example, instituting monthly rather than the current annual out-of-pocket spending limits could improve access to care and financial security while encouraging judicious use of health-care services by patients."

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