Online Sports Betting Legalization and Behavioral Health Care Use

Importance: The number of states with legal online sports betting has grown from 1 to 31 since 2018, expanding access to gambling. Despite the known behavioral health burdens associated with gambling, little is understood about legalization's impact on mental health and substance use treatment use. Objective: To evaluate the association between online sports betting legalization and treatment use for mental health conditions and substance use disorders (SUD). Design, Setting, and Participants: This was a quasi-experimental staggered difference-in-differences study using claims data from January 2016 to December 2023. The setting was a large, national convenience sample of people with employer-sponsored health insurance. Included in the analysis were men and women aged 18 to 64 years living in states that legalized online sports betting during 2018-2022 or had not by the end of the study period. Exposure: State legalization of online sports betting. Main Outcomes and Measures: Outcomes were measured at the state-year level, weighted by number of enrollees as follows: proportions of enrollees with 1 or more prescription fills for antidepressant, antianxiety, or SUD medications and proportions of enrollees with 1 or more outpatient, emergency department, or inpatient visits with a diagnosis for depression, anxiety, or SUD. Results: Among 61 951 305 enrollee-years, 31 914 852 (52%) were women, and the mean (SD) age was 41.9 (13.5) years. Online sports betting legalization was associated with increases in the probability of antidepressant use (men: 0.57 percentage points; 95% CI, 0.26-0.89 percentage points; women: 1.08 percentage points; 95% CI, 0.23-1.94 percentage points) and antianxiety use (men: 0.32 percentage points; 95% CI, 0.14-0.50 percentage points; women: 0.64 percentage points; 95% CI, 0.16-1.12 percentage points), but there was no detectable change in SUD medication use. Legalization was also associated with increases in the probability of an outpatient diagnosis for depression (men: 0.34 percentage points; 95% CI, 0.20-0.49 percentage points; women: 0.57 percentage points; 95% CI, 0.25-0.89 percentage points) and anxiety (men: 0.67 percentage points; 95% CI, 0.32-1.01 percentage points; women: 1.15 percentage points; 95% CI, 0.50-1.81 percentage points) but not SUD. Legalization was not associated with behavioral health diagnoses in the emergency department and inpatient settings. Conclusions and Relevance: Results of this quasi-experimental difference-in-differences study suggest that online sports betting legalization was associated with an increase in outpatient and prescription mental health care use among people with employer-sponsored health insurance. These findings underscore the importance of prevention and treatment of potential adverse health consequences of legalized online sports betting.