Association of coffee consumption and caffeine metabolism with arrhythmias and cardiac morphology: an observational, genetic and Mendelian Randomization study

Abstract

The association of coffee intake and caffeine metabolism with arrhythmias and cardiac structure is not fully understood. We aim to explore the associations of coffee intake and caffeine metabolism with the risk of certain types of arrhythmias, a broad range of cardiovascular imaging phenotypes, and potential gene-coffee interaction. Based on the UK Biobank imaging study, heart metrics were extracted via cardiovascular magnetic resonance (CMR) utilizing machine learning. Caffeine metabolism was determined by cytochrome P4501A2 gene (CYP1A2) or a polygenetic score of different genetic variants influencing caffeine metabolism. Genome-wide association data for two-sample Mendelian Randomization (MR) originated predominantly from individuals of European descent. A total of 34,992 individuals (mean [SD] age, 63.5 [7.5] years; 52.9% female) were assessed in the principal imaging analysis. Higher daily consumption of coffee was independently associated with higher left ventricular mass, larger global ventricular volume, higher ventricle stroke volume and larger atrial volume. The results were further supported by MR analysis. CYP1A2 and genetic score for caffeine metabolism were not associated with cardiovascular measurements (P>0.053 for all test). Coffee consumption was associated with a lower risk of sinus rhythm with short PR (per cup increase: Odds ratio, 0.90; 95%CI 0.82-0.99) and atrial fibrillation (0.89; 0.84-0.93). Coffee consumption was associated with a lower risk of atrial fibrillation, increased LV mass, elevated ventricle and larger atrial volume. Caffeine metabolism didn't significantly alter the association. Our results suggest that customary caffeine consumption limitations aimed at arrhythmia risk reduction might be unnecessary.