Abstract
INTRODUCTION: Coffee is a popular beverage and the most used psychostimulant worldwide. Habitual coffee consumption has been linked to a growing list of health benefits; however, coffee consumption has been a source of longstanding debate. Recent observational studies have challenged the misconception of caffeine and reported the safety and beneficial effects of coffee intake on a range of cardiovascular (CV) conditions, including coronary artery disease, arrhythmias, heart failure, and stroke, leading to a decreased risk of CVD, all-cause and CVD mortality, and being associated with favorable CV outcomes. However, the mechanisms underlying the protective effects of caffeine remain speculative, and there is a lack of dedicated studies aimed at addressing the impact of different coffee subtypes on clinical outcomes such as CVD, arrhythmia, and mortality. Study and Results: The study included 449,563 UK Biobank participants, free of cardiovascular problems at enrollment (median age 58 years; 55.3% females). The median follow-up time was 12.5 years. Drinking 4 to 5 cups/day of ground (HR 0.83; 95% CI [0.76-0.91]; P < .0001) or 2 to 3 cups/day of instant (HR, 0.88; 95% CI [0.85-0.92]; P < .0001) coffee (but not decaffeinated coffee) was associated with a significant reduction in incident arrhythmia, including AF. Habitual coffee intake of up to 5 cups/day was associated with significant reductions in the risk of incident CVD, CHD (HR 0.89, CI [0.86-0.91], P < 0.0001), CCF (HR 0.83, CI [0.79-0.87], P < 0.0001), and ischemic stroke (HR 0.84, CI [0.78-0.90], P < 0.0001). Coffee consumption led to significant reductions in all-cause mortality (HR 0.86, CI [0.83-0.89], P < 0.0001) and CV mortality (HR 0.82, CI [0.74-0.90], P < 0.0001). Consumption of ground coffee at all levels significantly reduced the risk of all-cause and CV mortality. There was no significant difference in the incidence of CVD among all intake categories or across all coffee subtypes. LESSONS LEARNED: The results from the UK Biobank indicate that mild-to-moderate consumption of all types of coffee is linked to improved CV outcomes and a lower risk of cardiovascular disease and death, with caffeinated coffee significantly reducing the risk of arrhythmias, including AF. Daily coffee intake should not be discouraged by physicians, even in the presence of a newly developed cardiovascular disease. Whether coffee will be prescribed in the future to prevent CVD and improve cardiovascular health depends on further evaluation of the physiological mechanisms and elucidation of the specific protective effects of coffee consumption.