Prescription use of benzodiazepines--a widely used class of sedative and anti-anxiety medications--increases steadily with age, despite the known risks for older people, according to a comprehensive analysis of benzodiazepine prescribing in the United States. Given existing guidelines cautioning health providers about benzodiazepine use among older adults, findings from the National Institutes of Health-funded study raise questions about why so many prescriptions--many for long-term use--are being written for this age group.
The study found that among all adults 18 to 80 years old, about 1 in 20 received a benzodiazepine prescription in 2008, the period covered by the study. But this fraction rose substantially with age, from 2.6 percent among those 18 to 35, to 8.7 percent in those 65 to 80, the oldest group studied. Long-term use--a supply of the medication for more than 120 days--also increased markedly with age. Of people 65 to 80 who used benzodiazepines, 31.4 percent received prescriptions for long-term use, vs. 14.7 percent of users 18 to 35. In all age groups, women were about twice as likely as men to receive benzodiazepines. Among women 65 to 80 years old, 1 in 10 was prescribed one of these medications, with almost a third of those receiving long-term prescriptions.
"These new data reveal worrisome patterns in the prescribing of benzodiazepines for older adults, and women in particular," said Thomas Insel, M.D., director of the National Institute of Mental Health (NIMH), which supported the study. "This analysis suggests that prescriptions for benzodiazepines in older Americans exceed what research suggests is appropriate and safe."
Benzodiazepines--named for their chemical structure--are among the most commonly prescribed medications in developed countries. They include alprazolam (Xanax), diazepam (Valium), and lorazepam (Ativan).The most common uses of benzodiazepines are to treat anxiety and sleep problems. While effective for both conditions, the medications have risks, especially when used over long periods. Long-term use can lead to dependence and withdrawal symptoms when discontinued. In older people, research has shown that benzodiazepines can impair cognition, mobility, and driving skills, and they increase the risk of falls.
Despite the large number of prescriptions in the United States--85 million in 2007--relatively little was known prior to this study about the specifics of benzodiazepine prescribing in the United States relative to other countries. Mark Olfson, M.D., M.P.H., at the New York State Psychiatric Institute and Columbia University; Marissa King, Ph.D., at Yale University; and Michael Schoenbaum, Ph.D., at NIMH used data from a national prescription database (IMS LifeLink LRx Longitudinal Prescription database) and a national database on medical expenditures collected by the Agency for Healthcare Research and Quality to examine prescription patterns from 2008.
These medications can pose real risks, and there are often safer alternatives available," said Dr. Schoenbaum, who was senior author. "Our findings strongly suggest that we need strategies to reduce benzodiazepine use, particularly for older women."
Among the findings:
- Use of benzodiazepines increased steadily with age: 5.2 percent of adults 18 to 80 years old received one or more benzodiazepine prescriptions in 2008; 2.6 percent of those 18 to 35, 5.4 percent of those 36 to 50, 7.4 percent of those 51 to 64, and 8.4 percent of those 65 to 80.
- Overall, about one quarter of prescriptions involve long-acting formulations of benzodiazepines.
- Most prescriptions for benzodiazepines are written by non-psychiatrists. For adults 18 to 80 years old, about two thirds of prescriptions for long-term use are written by non-psychiatrists; for adults 65 to 80, the figure is 9 out of 10.
Benzodiazepines are effective in relieving anxiety and take effect more quickly than antidepressant medications often prescribed for anxiety. However, the prevalence of anxiety disorders declines with age. Practice guidelines recommend nonpharmacologic approaches and antidepressants over benzodiazepines as first-line treatment. Rates of insomnia increase with age, but practice guidelines recommend that health care providers consider behavioral interventions as first-line treatment over medication. Neither of these conditions explains the rates of prescribing benzodiazepines for older age groups.
Adding to concerns about the possible health consequences of benzodiazepine use, a recently reported study found an association between benzodiazepine use in older people and increased risk of Alzheimer's disease. The association was stronger with increasing length of use; the risk was nearly doubled for those using benzodiazepines for more than 180 days.