The prevalence and short-term cardiovascular consequences of recent cannabis use in patients admitted to an intensive cardiac care unit for acute coronary syndrome is not well established.

To assess the prevalence of recent cannabis use detected by prospective systematic screening, and its prognostic value in predicting the occurrence of in-hospital major adverse events in consecutive patients with acute coronary syndrome.

From 07 to 22 April 2021, all consecutive patients admitted to an intensive cardiac care unit in 39 centres throughout France were studied prospectively. Systematic recreational drug screening was performed on admission by urine assay in all patients. The primary outcome was the prevalence of recent cannabis use. The secondary outcome was in-hospital major adverse events, defined by death, resuscitated cardiac arrest and cardiogenic shock requiring medical or mechanical haemodynamic support.

A total of 772 patients were hospitalized for acute coronary syndrome (mean age 64±13years; 74% male). Among those, 86 patients (11.1%) had a positive urine test for cannabis. Patients with cannabis detected were younger (53±12 vs. 65±12years, respectively; P<0.001) and were more frequently male (88% vs. 72%, respectively; P=0.001). After a median hospitalization duration of 2days, 33 (4.3%) in-hospital major adverse events occurred. The detection of cannabis was associated with a higher rate of in-hospital major adverse events after adjustment for prior co-morbidities (odds ratio 3.28; P=0.015) and after adjustment for known predictors of severity (odds ratio 3.68; P=0.009).

The prevalence of recent cannabis use in patients hospitalized for acute coronary syndrome was 11.1%. The detection of recent cannabis use was independently associated with a higher occurrence of in-hospital major adverse events.