The legalization of online betting, now available in 31 US states, was associated with statistically significant increases in treatment for depression and anxiety.

An analysis of insurance claims data from nearly 62 million enrollee-years of adults with employer-sponsored coverage showed that, after states legalized online sports betting, adults were more likely to fill prescriptions for antidepressants and antianxiety medications and to have outpatient visits for depression and anxiety. There were no such increases for substance use disorder treatment, emergency department visits, or hospitalizations.

Investigators found increases in both men and women, although the findings were more consistent and robust among men. The strength of these associations increased over the years following legalization, which the investigators said may reflect the lag between onset of problem gambling and treatment-seeking.

“Overall, these findings support the concern that there are broad mental health effects of online gambling legalization, though those who are experiencing those effects, and their clinicians, don’t necessarily attribute it to gambling,” first author Benjamin Westermeyer, a doctoral student at Johns Hopkins Bloomberg School of Public Health in Baltimore, said in a news release.

The study was published online on October 14 in JAMA Psychiatry.

Before and After Legalization

Following a 2018 US Supreme Court ruling that cleared the way for states to legalize sports betting, access to gambling through mobile apps expanded rapidly. By 2026, 31 states had legalized online sports betting.

Unlike traditional gambling, online betting offers virtually unlimited access, senior author Mark Meiselbach, PhD, of Johns Hopkins, noted in a JAMA Psychiatry podcast. “It’s not like you need to travel to a casino to bet,” he said. “So there’s really very limited barriers.” He also noted that opportunities to bet repeatedly during games may make the apps more addictive.

Previous research has linked gambling problems to depression, anxiety, substance use disorders, and financial distress. However, evidence of the broader mental health effects of online sports betting legalization has been limited and mixed.

To investigate, researchers analyzed commercial insurance claims between 2016 and 2023, covering nearly 62 million enrollee-years among adults aged 18-64 years (mean age, 42 years; 52% women). The analysis included 22 states that legalized online sports betting between 2018 and 2022 and 13 states that had not legalized sports betting by the end of 2023.

Using a difference-in-differences approach, the researchers compared changes in mental health care use before and after legalization with those in states where online betting was not yet legal. The approach accounted for baseline differences in treatment use and broader changes over time, although it could not rule out all potential confounding factors.

Legalization of online sports betting was associated with relative increases in the probability of filling an antidepressant prescription (5.44% for men and 5.00% for women) and of having an outpatient visit with a depression diagnosis (6.73% for men and 5.47% for women).

The findings were similar for anxiety, with 7.20% and 6.50% relative increases in the probability of an outpatient visit with an anxiety diagnosis, and 4.99% and 5.17% increases in antianxiety medication use, for men and women, respectively.

There was no significant increase in outpatient visits for substance use disorders or use of related medications, and no significant increase in emergency department visits or hospitalizations associated with depression, anxiety, or substance use disorders.

Differences in antidepressant and antianxiety prescription use between states with and without legalized online betting generally widened over time, with smaller increases in the first 1-2 years after legalization and larger differences emerging several years later.

A ‘Hidden Epidemic’

It takes time for a casual gambling habit to progress toward addiction, Westermeyer said, and the widening gap in mental health care use is “consistent with gambling problems developing over months and even years of usage.”

To address potential confounding, the investigators examined trends in mental health treatment prior to legalization. However, they found no significant differences in pre-legalization trends in antidepressant and antianxiety prescriptions between states that legalized online betting and those that had not.

For outpatient depression and anxiety visits, the researchers noted that states that legalized online sports betting may have already been on a slightly different trajectory than states that had not yet legalized it. Before legalization, differences in visit rates between the two types of states were small and nonsignificant, but that changed after legalization.

Financial losses and unfettered access to betting apps may worsen mental health, the investigators suggested. But the rise in treatment could also reflect greater awareness of available resources, prompting those with untreated depression or anxiety to seek care.

The researchers cautioned that the analysis was limited to individuals with employer-sponsored insurance, and claims data can’t show whether patients receiving mental health treatment had bet on sports themselves.

Meiselbach urged clinicians to ask patients about online sports betting, even without formal gambling disorder screening, as a possible contributor to depression or anxiety.

That message resonated with John Torous, MD, director of the Digital Psychiatry Division at Beth Israel Deaconess Medical Center in Boston, and host of the JAMA Psychiatry podcast.

Torous described online sports betting a “hidden epidemic,” fueled by easy access to betting apps and prediction markets. “We don’t routinely screen for it, but I can see merit in bringing it up,” he said.

The study had no commercial funding. Author disclosures are available with the original study publication. Torous had no relevant disclosures.