OBJECTIVE: Little is known about patients who skip doses or otherwise avoid using their medications because of cost. We sought to identify
which elderly patients are at highest risk of restricting their medications because of cost, and how prescription coverage
modifies this risk.
DESIGN AND PARTICIPANTS: Cross-sectional study from the 1995–1996 wave of the Survey of Asset and Health Dynamics Among the Oldest Old, a population-based
survey of Americans age 70 years and older.
MEASUREMENTS: Subjects were asked the extent of their prescription coverage, and whether they had taken less medicine than prescribed for
them because of cost over the prior 2 years. We used bivariate and multivariate analyses to identify risk factors for medication
restriction in subjects who lacked prescription coverage. Among these high-risk groups, we then examined the effect of prescription
coverage on rates of medication restriction.
MAIN RESULTS: Of 4,896 seniors who regularly used prescription medications, medication restriction because of cost was reported by 8% of
subjects with no prescription coverage, 3% with partial coverage, and 2% with full coverage (P<.01 for trend). Among subjects with no prescription coverage, the strongest independent predictors of medication restriction
were minority ethnicity (odds ratio [OR], 2.9 compared with white ethnicity; 95% confidence interval [95% CI], 2.0 to 4.2),
annual income <$10,000 (OR, 3.8 compared with income ≥$10,000 (OR, 3.8 compared with income ≥20,000; 95% CI, 2.4 to 6.1), and out-of-pocket prescription drug costs
>$100 per month (OR, 3.3 compared to costs ≤$100 per month (OR, 3.3 compared to costs ≤20; 95% CI, 1.5 to 7.2). The prevalence of medication restriction in members
of these 3 risk groups was 21%, 16%, and 13%, respectively. Almost half (43%) of subjects with all 3 risk factors and no prescription
coverage reported restricting their use of medications. After multivariable adjustment, high-risk subjects with no coverage
had 3 to 15 times higher odds of medication restriction than subjects with partial or full coverage (P<.01).
CONCLUSIONS: Medication restriction is common in seniors who lack prescription coverage, particularly among certain vulnerable groups.
Seniors in these high-risk groups who have prescription coverage are much less likely to restrict their use of medications.
Key words insurance - pharmaceutical services - health services accessibility - prescriptions - drug - fees - pharmaceutical - aged
Presented as an oral presentation at the American Geriatrics Society Annual Meeting, Chicago, May, 2001; the Society of General
Internal Medicine Annual Meeting, San Diego, May, 2001; and the Northern California Epidemiology Network Conference, Berkeley,
February, 2001.
Dr. Steinman was supported in part by the VA National Quality Scholars Fellowship Program. Dr. Covinsky was supported in part
by an Independent Scientist Award from the Agency for Healthcare Research and Quality (K02HS00006-01) and is a Paul Beeson
Faculty Scholar in Aging Research.