Effect of switching to a high-deductible health plan on use of chronic medications

Health Serv Res. 2011 Oct;46(5):1382-401. doi: 10.1111/j.1475-6773.2011.01252.x. Epub 2011 Mar 17.


Objective: To examine whether high-deductible health plans (HDHPs) that exempt prescription drugs from full cost sharing preserve medication use for major chronic illness, compared with traditional HMOs with similar drug cost sharing.

Data sources/study setting: We examined 2001-2008 pharmacy claims data of 3,348 continuously enrolled adults in a Massachusetts health plan for 9 months before and 24 months after an employer-mandated switch from a traditional HMO plan to a HDHP, compared with 20,534 contemporaneous matched HMO members. Both study groups faced similar three-tiered drug copayments. We calculated daily medication availability for all prescription drugs and four chronic medication classes: hypoglycemics, lipid-lowering agents, antihypertensives, and chronic obstructive pulmonary disease (COPD)/asthma controllers.

Study design: Interrupted time-series with comparison group study design examining monthly level and trend changes in prescription drug utilization.

Principal findings: The HDHP and control groups had comparable changes in the level and trend of all drugs after the index date; we detected similar patterns in the use of lipid-lowering agents, antihypertensives, and COPD/asthma controllers. Some evidence suggested a small relative decline in hypoglycemic use among diabetic patients in HDHPs.

Conclusions: Switching to an HDHP that included modest drug copayments did not change medication availability or reduce use of essential medications for three common chronic illnesses.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Asthma / drug therapy
  • Case-Control Studies
  • Chi-Square Distribution
  • Cost Sharing / economics
  • Deductibles and Coinsurance / economics*
  • Diabetes Mellitus / drug therapy
  • Female
  • Health Maintenance Organizations / economics
  • Health Services Accessibility
  • Health Services Research
  • Humans
  • Hyperlipidemias / drug therapy
  • Hypertension / drug therapy
  • Insurance Claim Review
  • Insurance, Pharmaceutical Services / economics*
  • Male
  • Massachusetts
  • Middle Aged
  • Pulmonary Disease, Chronic Obstructive / drug therapy