Associations Between Monthly Cannabis Use and Myocardial Infarction in Middle-Aged Adults: NHANES 2009 to 2018

Abstract

Mechanistic research suggests using Cannabis sativa L. (cannabis or marijuana) may increase the risk of cardiometabolic disease, but observational studies investigating associations between cannabis use and myocardial infarction (MI) have reported inconsistent results. Cross-sectional National Health and Nutrition Examination Survey data from five 2-year cycles between 2009 and 2018 and representing 9,769 middle-aged adults (35 to 59 years old) were analyzed. Multivariable logistic regression models accounting for sampling weights and adjusting for cardiovascular risk factors were used to assess associations between a history of monthly cannabis use before MI and a subsequent MI. A quarter of respondents (n = 2,220) reported a history of monthly use >1 year before an MI. A history of MI was reported by 2.1% of all respondents and 3.2.% of those who reported a history of monthly use. In fully adjusted multivariable models, and compared with never use, a history of monthly cannabis use preceding an MI was not associated with an MI (odds ratio [OR] 0.78, 95% confidence interval [CI] 0.35 to 1.71). However, when stratified by recent use, the odds of MI were threefold greater (OR 2.98, 95% CI 1.08 to 8.60) when no use was reported within the past month than when use was reported within the past month. Duration of monthly use was also not significantly associated with MI, including monthly use >10 years (OR 0.78, 95% CI 0.30 to 2.01). In conclusion, in a representative sample of middle-aged US adults, a history of monthly cannabis use >1 year before an MI was not associated with a subsequent physician-diagnosed MI, except for threefold greater odds when cannabis was not used within the past month.

Keywords: cannabis; cardiovascular disease; marijuana; myocardial infarction.

Figure 1.. Flowchart of the analytic sample (unweighted).

Notes: subgroups are represented by unweighted frequencies and weighted percentages. *This question was administered to all respondents reporting ever using marijuana or hashish. Only responses from those with a history of monthly use >1 year were analyzed. †Years of monthly cannabis use before MI was determined by responses to the following questions: “How old were you when you started smoking marijuana or hashish at least once a month for one year?” (age in years) and “How long has it been since you last smoked marijuana or hashish at least once a month for one year?” Years of monthly use were calculated by subtracting the number of years since using it monthly for a year from a respondent’s current age and then subtracting the age at which they reported starting using it monthly for a year. If the number of years since a reported MI was greater than the number of years since monthly use, the difference was subtracted from the number of years of monthly use, resulting in years of monthly use before the MI.