UC San Diego: 1 in 9 Older Cannabis Users Meet Use Disorder Criteria

More than one in nine Americans age 65 and older who used cannabis in the past year met the diagnostic criteria for cannabis use disorder, according to a study published Sept. 28 in the journal Addiction by researchers at UC San Diego School of Medicine. The findings, drawn from a nationally representative sample of 21,189 older adults, are the most detailed look yet at how often cannabis use becomes compulsive in a population that is using the drug in growing numbers.

Among older adults reporting past-year cannabis use, 11.4% met criteria for cannabis use disorder — a pattern of use that causes problems or interferes with daily life. Most cases were mild: 76% of those who screened positive fell into the mild category, 20.1% moderate and 3.9% severe.

The analysis pooled data from the 2021–2024 National Survey on Drug Use and Health, the federal survey used to track substance use nationally. The researchers estimate that about 8.9% of adults 65 and older used cannabis in the past year.

What the criteria actually measure

The most commonly reported symptoms were the hallmarks of dependence rather than acute intoxication. Nearly three-quarters of older adults who met criteria — 74.4% — said they spent a great deal of time obtaining, using or recovering from cannabis. Craving was reported by 67.5%, and tolerance by 48.3%.

"While there is a lot of attention on how cannabis may help common chronic symptoms older adults experience or the possible acute adverse effects in this population, less focus has been on cannabis use disorder," said Benjamin Han, MD, an assistant professor at UC San Diego School of Medicine and the study's lead author. "It is important to recognize that any psychoactive substance, including cannabis, can lead to a harmful pattern of use, including among older adults."

Frequency of use is the strongest signal

The likelihood of meeting criteria rose sharply with how often someone used cannabis. Older adults who used the drug on at least 300 days in the past year were almost four times more likely to meet criteria for cannabis use disorder than those who used it less often. Smoking was the most common method of use, reported by 65.8% of past-year users, followed by eating or drinking cannabis products at 40.5% and vaping at 15.4%.

Smoking cannabis was independently associated with use disorder, as were three other factors: past-year mental illness, tobacco use, and use of drugs other than cannabis. That overlap places many of the affected older adults at the intersection of substance use and mental health conditions — the pattern clinicians call a dual diagnosis.

The researchers also found that about one in five older adults who used cannabis in the past year — 19.9% — said a doctor had recommended some or all of that use.

A population with unusual exposure

Older adults may absorb more risk per joint than younger users. Age-related changes in the body slow drug metabolism, and older adults carry a higher burden of chronic disease and prescription medication use, which raises the odds of interactions. Earlier research has linked cannabis use in this group to chronic disease, cognitive impairment, falls, cannabis poisoning and cannabis-related emergency department visits.

"Any psychoactive substance, including cannabis, can lead to a harmful pattern of use, including among older adults," Han said.

That combination — more prescriptions, more chronic conditions and a drug increasingly marketed as a remedy for both — leaves primary care as the logical place to catch problem use. The study's authors argue for exactly that, calling for routine screening of older adults for unhealthy cannabis use and for clinicians to discuss cannabis as part of ordinary health care rather than as an afterthought at the end of a visit.

Treatment options remain thin

Cannabis use disorder is the most common illicit-drug use disorder in the United States and the only one of the major substance use disorders with no FDA-approved medication. There is no cannabis equivalent of buprenorphine or naltrexone. Treatment relies on behavioral approaches such as cognitive behavioral therapy, contingency management and mutual-help groups, along with medication to manage withdrawal symptoms like insomnia and anxiety.

Outpatient counseling programs that deliver those therapies through standard outpatient care exist in most states, but clinicians report low rates of referral for cannabis specifically, in part because patients often do not view their use as a problem and because screening questions in older populations skew toward alcohol and prescription drugs.

The paper arrives weeks after other federal data showed the broader problem is widening. Research from the National Institute on Drug Abuse published in August found that cannabis use disorder among U.S. adults rose from 15.3 million people in 2021 to 19.4 million in 2024, even as alcohol use disorder declined. The authors of that work attributed the trend largely to rising THC concentrations in legal-market products and to expanding legalization.

The new study points in the same direction for a group that is easy to overlook: the 76% of cases that were mild mean many older adults could be helped by a conversation and a referral rather than intensive treatment, if the screening happens at all. Information about cannabis dependence and how it is treated is available for patients and families weighing whether their own use has crossed a line.

The study was supported by grants from the National Institute on Drug Abuse and the UC San Diego Sam and Rose Stein Institute for Research on Aging. Co-authors include Evan Eschliman of Duke University, Joseph Palamar of New York University, and Mireia Triguero Roura and Pia Mauro of Rutgers Health.