Cannabis use linked with pacemaker-requiring AV block risk

BACKGROUND: Recent studies focused on atrial fibrillation have demonstrated that the etiology of cardiac arrhythmias may be influenced by modifiable risk factors. It remains unknown if similar predictors are relevant to bradyarrhythmias, the most severe form being atrioventricular (AV) block warranting a pacemaker. This study aimed to identify predictors of AV block warranting a pacemaker. METHODS: We used the California Health Care Access and Information databases to identify Californians ≥18 years who received care in an emergency department, outpatient surgery facility, or hospital in 2005-2020. We examined demographics, comorbidities, lifestyle factors, and air pollution levels as potential predictors. Outcome and covariates were identified using ICD-9, ICD-10, and CPT codes. We used multivariable adjusted Cox proportional models to identify predictors of pacemaker implantation for AV block. RESULTS: Among 28,640,453 patients, the mean age was 44.2 ± 19.3 years, 54% were female, and 0.3% received a pacemaker for AV block over a mean follow-up of 9.8 ± 4.8 years. In the fully adjusted model, 19 predictors were associated with an increased risk of pacemaker implantation for AV block, including older age, male sex, and cardiovascular comorbidities; modifiable lifestyle factors included heavy alcohol use, use of tobacco, cannabis consumption, and obesity. Asian and Pacific Islanders and Blacks were at lower risk compared to Whites. CONCLUSIONS: This large cohort study identified several modifiable risk factors that may be the focus of future strategies to reduce the risk of AV block warranting a pacemaker.