Marijuana use and subjective cognitive decline in middle-aged and older adults: Analysis of the behavioral risk factor surveillance system survey

BackgroundMarijuana impairs the brain development and function among adolescents, but little is known about whether marijuana use is associated with subjective cognitive decline (SCD) among adults.ObjectiveWe investigated the cross-sectional association between marijuana use and past-year SCD in a representative sample of US adults aged 45 years and older.MethodsThe study population included 100,685 participants from five cycles of the Behavioral Risk Factor Surveillance System (BRFSS). Participants self-reported their marijuana use in the past month and whether they experienced SCD or SCD-related functional limitations in the past year. Participants were categorized into past-month marijuana non-users and past-month marijuana users. Among users, they were further classified as occasional (<10 days) and frequent users (≥10 days). The weighted, multivariable logistic regression models were fitted to examine the association between marijuana use and past-year SCD, adjusting for age, sex, educational level, chronic disease status, and other potential confounders.ResultsThe sample included 94.2% (94,818/100,685) of past-month marijuana non-users and 5.83% (5867/100,685) of users. Among the users, 59.3% (3477/5867) were frequent users. Compared with past-month marijuana non-use, past-month marijuana use was significantly associated with higher odds of past-year SCD (OR = 1.70, 95% CI: 1.41, 2.05). The higher frequency was associated with higher odds of having past-year SCD in a dose-response manner (<i>p</i> Trend < 0.001). Similar associations remained for the SCD-related functional limitations.ConclusionsWe found that past-month marijuana users reported higher rates of past-year SCD, a finding consistent with prior literature linking marijuana use with cognitive decline. Future prospective studies are warranted to confirm these findings.