Enrolment in high-deductible health plan may not be linked to asthma exacerbations How does the switch to a high-deductible health plan affect children with asthma? A new study led by researchers at the Harvard Pilgrim Health Care Institute suggests that enrollment in a high-deductible health plan (HDHP) may not be associated with changes in asthma medication use or asthma exacerbations when medications are exempt from the deductible. The findings were published in JAMA Pediatrics on May 10. To treat asthma, clinical guidelines recommend the use of controller medications, but adherence to these medications is generally suboptimal, putting those affected at risk for asthma exacerbations. High out-of-pocket costs have been associated with decreased controller medication use and adverse asthma outcomes for children and adults.