Dana P. Goldman, Ph.D., of RAND, Santa Monica, Calif., and colleagues analyzed previous studies to determine how cost-sharing features of prescription drug benefits may affect access to prescription drugs and how these features may affect medical spending and health outcomes. For this analysis, the researchers identified 132 articles examining the associations between prescription drug plan cost-containment measures, including co-payments, tiering, or coinsurance, pharmacy benefit caps (limit on how much the insurance company will pay for medications during a year) or monthly prescription limits, formulary restrictions, and reference pricing, and outcomes, including pharmacy utilization and spending, medical care utilization and spending, and health outcomes.
Results of this review:
The results of this review are not surprising:
- Increased cost sharing is associated with:
· lower rates of drug treatment,
· worse adherence to treatment regimens among existing users,
· and more frequent discontinuation of medications.
- For each 10% increase in cost sharing, prescription drug spending decreases by 2% to 6%, depending on class of drug and condition of the patient.
- The reduction in use associated with a benefit cap, which limits either the coverage amount or the number of covered prescriptions, is consistent with other cost-sharing features.
- For some chronic conditions, higher cost sharing is associated with increased use of medical services, at least for patients with congestive heart failure, lipid disorders, diabetes, and schizophrenia.
- While low-income groups may be more sensitive to increased cost sharing, there is little evidence to support this contention.
Conclusions of the review:
“These findings make benefit design an important public health tool for improving population health. The challenge for public and private plans is to make patients more sensitive to the cost of treatment without encouraging them to forego cost-effective care. This requires knowing how patients respond to different incentives and cataloging the net benefits of alternative therapies, not only for health, but also for current and future health care costs, productivity, and patient utility.” 1
(JAMA. 2007;298(1):61-69. Available pre-embargo to the media at www.jamamedia.org)
Resources:
1 Goldman, Dana P., PhD; Joyce, Geoffrey F., Phd; Zeng, Yuhui, MPhil. “Prescription Drug Cost Sharing Associations With medication and medical Utilization and Spending and Health. JAMA. 2007;298(1):61-69.
2 Press Release. “Increase in Prescription Drug Cost Sharing Associated With Lower Rates of Drug Treatment, Adherence.” Chicago. American Medical Association. July 3, 2007.
