Association between coffee or tea consumption and cardiovascular outcomes in patients with stable coronary artery disease: Analysis from the CLARIFY registry.

Background: Conflicting data exist on the association between consumption of coffee or tea and cardiovascular outcomes, and few focus on patients with established coronary artery disease.

Aim: To describe the association between coffee or tea consumption and cardiovascular outcomes in patients with stable coronary artery disease, using an extensive contemporary international registry, allowing the identification of multiple potential confounders.

Methods: The Prospective Observational Longitudinal Registry of Patients With Stable Coronary Artery Disease (CLARIFY) registry enrolled in 2009 and 2010 in 45 countries, with a 5-year follow-up. Patients were categorized according to daily consumption of coffee or tea, and were compared with those declaring neither. The primary composite outcome of myocardial infarction, stroke or cardiovascular death was analysed at 5years, as well as all-cause mortality. Sensitivity analyses were performed with a multivariable model.

Results: A total of 15,459 and 10,029 patients declared coffee or tea consumption, respectively. At 5years, after full adjustment, no association was found between coffee consumption and the primary outcome: hazard ratio 1.04 (95% confidence interval 0.89-1.21) for 1 cup; 0.94 (0.82-1.08) for 2-3 cups; and 1.04 (0.86-1.27) for ≥4 cups (P=0.51). Drinking tea was not associated with a different incidence of the primary outcome before or after adjustment, with fully adjusted hazard ratios of 1.08 (95% confidence interval 0.84-1.38) for 1 cup, 1.12 (0.96-1.31) for 2-3 cups and 0.95 (0.79-1.14) for ≥4 cups (P=0.30). After full adjustment, neither coffee nor tea drinking was associated with all-cause mortality.

Conclusions: In outpatients with stable coronary artery disease, there was no association between coffee or tea consumption and ischaemic outcomes or all-cause mortality.