Sleep medications associated with higher risk for dementia in white individuals

White individuals who frequently used sleep medication had a greater risk for dementia compared with those who rarely or never used them, though the same association was not found in Black individuals, a new study found.

“Despite the growing concern over the short-term adverse events related to sleep medication use in older adults, such as increased risk for falls and acute memory loss, the long-term effects of sleep medications on cognitive decline and risk for dementia in older adults of different ethnicities remain controversial,” Yue Leng, PhD, an assistant professor in the department of psychiatry and behavioral sciences at the University of California, San Francisco, and colleagues wrote in the Journal of Alzheimer’s Disease

Additionally, “while Black older adults are often less likely to report hypnotics use, yet more likely to develop dementia than whites, almost nothing is known about whether the association between hypnotics use and risk for dementia might differ by race,” according to the researchers.

Leng and colleagues retrieved data from the Health, Aging and Body Composition perspective cohort. Of the 3,068 participants aged 70 to 79 years who completed the baseline questionnaire, 41.7% were Black, and 51.5% were women.

During a baseline period from 1997 to 1998, participants were asked about the frequency of sleep medication use, in which they chose one of several responses:

• “never”;
• “rarely,” defined as once a month or less;
• “sometimes,” defined as two to four times a month;
• “often,” defined as five to 15 times a month; or
• “almost always,” defined as 16 to 30 times a month.

Participants once again completed questionnaires during follow up from 1999 to 2000 and from 2000 to 2002.

Trends in medication use

Overall, 4.1% of Black participants and 5.9% of white participants took over-the-counter hypnotics, while 6.1% of Black participants and 10.2% of white participants took prescription hypnotics.

Nearly 6% of respondents reported taking sleep medication often or almost always. White participants were about three times more likely to take sleep medication often or always compared with Black participants (7.7% vs. 2.7%).

“More frequent users of sleep medications were more likely to be women, had higher education and more depressive symptoms and were less likely to have diabetes,” Leng and colleagues wrote.

Notably, the researchers found that white participants were twice as likely to take benzodiazepines and 10 times as likely to take trazadone compared with Black participants. White participants also had a greater likelihood of using nonbenzodiazepines, or Z-drugs.

Risk for dementia

Overall, 20% of participants developed dementia during the study period. After adjusting for covariates, the researchers observed a greater risk for dementia among white individuals who sometimes, often or almost always (HR = 1.79; 95% CI, 1.21-2.66) used sleep medication compared with white individuals who never or rarely used sleep medication.

There was no significant association among Black individuals. The researchers suggested that this may be because Black individuals who had access to sleep medication are “a selected group of participants who had greater cognitive reserve and were less susceptible to dementia risk.”

“Indeed, participants who reported taking sleep medications more frequently had higher education level,” they wrote. “Moreover, Blacks are known to have worse sleep quality and thus frequent hypnotics use in Blacks have helped mitigate dementia risk more by improving the sleep quality of this population.”

Racial bias in prescribing patterns of controlled substances may also play a role, “and thus the different types of sleep medications received by Blacks and Whites could have contributed to the different risk of dementia in these populations,” the researchers wrote.

“Indeed, this study and others have shown that Black older adults were significantly less likely to receive prescriptions for benzodiazepines as compared to non-Hispanic whites,” Leng and colleagues wrote.

While the long-term impact of sleep medication on brain cognition remains unknown, the researchers pointed out that the association between medication use and dementia risk in their study “was independent of sleep duration and disturbances, which argues against the use of hypnotics among individuals at high risk for cognitive impairment.”

Leng told Healio that primary care providers should pay closer attention to patients’ sleep conditions and carefully consider different treatment options.

“In general, nonpharmacological sleep interventions (eg, cognitive behavioral therapy for insomnia) are encouraged as safer options,” she said.

Leng also warned that the study findings “need to be interpreted with caution.”

“We just showed an ‘association’ but cannot prove causality. In other words, we can’t conclude that sleep medications themselves are harmful,” she said. “Further studies are needed to confirm whether sleep medications themselves are harmful for cognition in older adults or frequent use of sleep medications is an indicator of something else that links to an increased dementia risk.”

References:

• Do sleep medications increase your chances of dementia? https://www.eurekalert.org/news-releases/978022. Published Jan. 31, 2023. Accessed Feb. 1, 2023.
• Leng Y, et al. J Alzheimers Dis. 2023;doi:10.3233/JAD-221006.