Marijuana Use Affects Young Adult Sleep Patterns.
Daily marijuana users reported more sleep disturbance than people who used marijuana less often or not at all, countering the perception that the drug helps to treat insomnia, according to a new study co-authored by a School of Public Health researcher.
The study, in the Journal of Addictive Diseases, found that daily marijuana users scored higher on the Insomnia Severity Index and sleep-disturbance measures than non-daily users. Ninety-eight marijuana users, most in their early 20s, participated in the study, which was co-authored by Michael Stein, chair of health law, policy & management and the study’s principal investigator.
“Better sleep is one of the positive effects that marijuana users swear by, but there has been relatively little careful research on this topic,” Stein said.
In the study, he and colleagues cited previous research indicating that as many as one-third of young adults, ages 18 to 25, complain of sleep problems. The findings showed an association between heavy marijuana use and such sleep difficulties.
“The effects of marijuana on sleep in intermittent users may be similar, in part, to those of alcohol, where improvements in sleep continuity measures have been reported with intermittent use, (but) daily use results in the worsening of sleep,” the researchers wrote.
They found a lack of difference in the sleep characteristics of non-daily users (people who smoked on at least one day in the past month and up to five days per week), compared to non-users. Daytime sleepiness also did not differ among heavy users, lighter users, and non-users.
“Sleep disturbance, which is common in this age group, may not be increased by non-daily [marijuana] use,” the study says. The researchers noted that daily users typically reported smoking marijuana in the daytime and at night, while less frequent users smoked primarily at night.
Because the findings suggest that anxiety is “significantly related” to reports of sleep disturbance, Stein and colleagues recommended that future studies look at mood disorders in the relationship between marijuana use and sleep. People with anxiety may be using marijuana to try to mitigate their sleep problems, they said.
The research team urged more study of the issue, so that health providers could talk more clearly to marijuana users about effects on sleep, and drug-treatment providers could “meaningfully target sleep” among heavy marijuana users.
The study was led by Dierdre Conroy of the University of Michigan Addiction Research Center. Co-authors were from Brown University and the University of California, San Diego.