ContextPrescription drugs are instrumental to managing and preventing chronic disease. Recent changes in US prescription drug cost sharing could affect access to them.ObjectiveTo synthesize published evidence on the associations among cost-sharing features of prescription drug benefits and use of prescription drugs, use of nonpharmaceutical services, and health outcomes.Data SourcesWe searched PubMed for studies published in English between 1985 and 2006.Study Selection and Data ExtractionAmong 923 articles found in the search, we identified 132 articles examining the associations between prescription drug plan cost-containment measures, including co-payments, tiering, or coinsurance (n = 65), pharmacy benefit caps or monthly prescription limits (n = 11), formulary restrictions (n = 41), and reference pricing (n = 16), and salient outcomes, including pharmacy utilization and spending, medical care utilization and spending, and health outcomes.ResultsIncreased cost sharing is associated with lower rates of drug treatment, worse adherence among existing users, and more frequent discontinuation of therapy. 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.ConclusionsPharmacy benefit design represents an important public health tool for improving patient treatment and adherence. While increased cost sharing is highly correlated with reductions in pharmacy use, the long-term consequences of benefit changes on health are still uncertain.

Research from JAMA — Pharmacy Benefits and the Use of Drugs by the Chronically Ill — ContextMany health plans have instituted more cost sharing to discourage use of more expensive pharmaceuticals and to reduce drug spending.ObjectiveTo determine how changes in cost sharing affect use of the most commonly used drug classes among the privately insured and the chronically ill.Design, Setting, and ParticipantsRetrospective US study conducted from 1997 to 2000, examining linked pharmacy claims data with health plan benefit designs from 30 employers and 52 health plans. Participants were 528 969 privately insured beneficiaries aged 18 to 64 years and enrolled from 1 to 4 years (960 791 person-years).Main Outcome MeasureRelative change in drug days supplied (per member, per year) when co-payments doubled in a prototypical drug benefit plan.ResultsDoubling co-payments was associated with reductions in use of 8 therapeutic classes. The largest decreases occurred for nonsteroidal anti-inflammatory drugs (NSAIDs) (45%) and antihistamines (44%). Reductions in overall days supplied of antihyperlipidemics (34%), antiulcerants (33%), antiasthmatics (32%), antihypertensives (26%), antidepressants (26%), and antidiabetics (25%) were also observed. Among patients diagnosed as having a chronic illness and receiving ongoing care, use was less responsive to co-payment changes. Use of antidepressants by depressed patients declined by 8%; use of antihypertensives by hypertensive patients decreased by 10%. Larger reductions were observed for arthritis patients taking NSAIDs (27%) and allergy patients taking antihistamines (31%). Patients with diabetes reduced their use of antidiabetes drugs by 23%.ConclusionsThe use of medications such as antihistamines and NSAIDs, which are taken intermittently to treat symptoms, was sensitive to co-payment changes. Other medications—antihypertensive, antiasthmatic, antidepressant, antihyperlipidemic, antiulcerant, and antidiabetic agents—also demonstrated significant price responsiveness. The reduction in use of medications for individuals in ongoing care was more modest. Still, significant increases in co-payments raise concern about adverse health consequences because of the large price effects, especially among diabetic patients.

Recent innovations in biomedicine seem poised to revolutionize medical practice. At the same time, disease and disability are increasing among younger populations. This paper considers how these confluent trends will affect the elderly's health status and health care spending over the next thirty years. Because healthier people live longer, cumulative Medicare spending varies little with a beneficiary's disease and disability status upon entering Medicare. On the other hand, ten of the most promising medical technologies are forecast to increase spending greatly. It is unlikely that a “silver bullet” will emerge to both improve health and dramatically reduce medical spending.

The foreign-born represent a disproportionate share of nonelderly U.S. adults without health insurance. Using data from Los Angeles County, we find that most of the insurance disparities between the foreign-born and native-born can be explained by traditional socioeconomic factors. Undocumented immigrants, however, have lower rates of coverage-both private and public-even after a wide array of factors are controlled for. Applying Los Angeles County rates to the U.S. population implies that undocumented immigrants account for one-third of the total increase in the number of uninsured adults in the United States between 1980 and 2000.

In this paper we examine spending by privately insured patients with four conditions often treated with specialty drugs: cancer, kidney disease, rheumatoid arthritis, and multiple sclerosis. Despite having employer-sponsored health insurance, these patients face substantial risk for high out-of-pocket spending. In contrast to traditional pharmaceuticals, we find that specialty drug use is largely insensitive to cost sharing, with price elasticities ranging from 0.01 to 0.21. Given the expense of many specialty drugs, care management should focus on making sure that patients who will most benefit receive them. Once such patients are identified, it makes little economic sense to limit coverage.