Heavy cannabis use may spell increased risk of cardiac death for women

Heavy lifetime use of cannabis among women contributes to increased risk of death from cardiovascular disease (CVD), as reported in a study.

Researchers examined the specific causes of mortality in relation to cannabis use among 121,895 UK Biobank participants. The participants completed a questionnaire that assessed cannabis use status, which was categorized as heavy, moderate, low, and never.

Outcomes included all-cause, CVD, and cancer mortality. Data on causes of death were obtained from the National Health Service Information Centre.

Of the participants, 54.51 percent were females (mean age 55.15 years) and 45.49 percent were males (mean age 56.46 years). Over a median follow-up of 11.80 years, a total of 2,375 cases of death were documented, including 1,411 deaths from CVD and 440 from cancer.

In fully-adjusted Cox proportional hazard regression models, heavy cannabis use was associated with CVD mortality compared with never-use among female users (hazard ratio [HR], 2.67, 95 percent confidence interval [CI], 1.19-4.32) but not among male users (HR, 0.98, 95 percent CI, 0.43–2.25).

For other outcomes, the HRs associated with heavy cannabis use were 1.28 (95 percent CI, 0.90–1.81) for all-cause mortality and 1.09 (95 percent CI, 0.71–1.67) for cancer mortality among male users, and 1.49 (95 percent CI, 0.92–2.40) and 1.61 (95 percent CI, 0.91–2.83) among female users, respectively.

Among female current tobacco users, heavy cannabis use versus never use was associated with all-cause mortality (HR, 2.25, 95 percent CI, 1.12-4.53), CVD mortality (HR, 2.56; 95% CI, 1.43-15.36), and cancer mortality (HR, 3.52, 95 percent CI, 1.50-8.33) and among never tobacco users with CVD mortality (HR, 2.98, 95 percent CI, 1.67-6.61).

Among male current tobacco users, heavy cannabis use was associated with cancer mortality (HR, 2.44, 95 percent CI, 1.14–5.23).