Recent cannabis use and self-rated health in young and middle-aged adults: a propensity score-weighted analysis of the National Health and Nutrition Examination Survey (NHANES)

Introduction: Self-rated health is an important patient-centred measure of health. The relationship between cannabis use and self-rated health has been previously studied, although with methodologic concerns which we aimed to address in this investigation. Methods: Propensity score weighted analyses of the National Health and Nutrition Examination Survey (NHANES) 2009-2018 were conducted. The primary exposure was self-reported cannabis use in the 30 days prior to survey response. The primary outcome was self-rated health measured on a five-level ordinal scale. Secondary outcomes included the number of days in the past months with: i) poor physical health, ii) poor mental health, and iii) activity limitations related to poor health. A weighted proportional odds regression model was used for the primary analysis and weighted zero-inflated negative binomial regression models were used for each secondary analysis. Results: Among 22,055 adults aged 20-59 responding to the NHANES cannabis questionnaire, 14.4% endorsed use in the past 30 days. After reweighting the sample to balance cannabis users and non-users across sociodemographic, medical, and lifestyle characteristics, there was no statistically significant association between recent cannabis use and higher levels of self-rated health (OR 0.90, 95% CI 0.80-1.01). Cannabis use was associated with poor mental health and activity limitations in the past month, but not poor physical health. Conclusions: Recent cannabis use was not associated with self-rated health but was associated with poor mental health and activity limitations in the past month. Cannabis users at risk of poor mental health should be connected with clinicians to help guide therapy.