Cardiovascular symptoms influence coffee consumption

People tend to innately control their consumption of coffee based on their blood pressure (BP) levels and heart rate, as shown in a study that provides a causal genetic evidence for cardiovascular system-driven influences on habitual coffee intakes.

Data from 390,435 European ancestry participants aged 39–73 years in the UK Biobank were used in this study. Habitual coffee consumption was self-reported, while systolic (S)BP, diastolic (D)BP, and heart rate were measured at baseline. Cardiovascular symptoms at baseline were drawn from hospital diagnoses, primary care records, or self-report.

Finally, the authors examined genetic evidence for a causal relationship between SBP, DBP, and heart rate with habitual coffee consumption using Mendelian randomization (MR).

Individuals with essential hypertension, angina, or heart arrhythmia were less likely to drink caffeinated coffee and more likely to be nonhabitual or decaffeinated coffee drinkers than those who did not report related symptoms (p≤3.5x10^-8 for all comparisons).

Higher SBP and DBP correlated with lower consumption of caffeinated coffee at baseline, with consistent genetic evidence supporting a causal explanation across all methods (per 10-mm Hg higher SBP: MR-Egger regression β, –0.21 cups/day, 95 percent confidence interval [CI], –0.34 to –0.07; per 10-mm Hg higher DBP: MR-Egger regression β, –0.33, 95 percent CI, –0.61 to –0.07).

Genetic analyses showed an association between a higher resting heart rate and a higher likelihood of being a decaffeinated coffee drinker (per 10 beats/min: MR-Egger regression odds ratio, 1.71, 95 percent CI, 1.31–2.21).

“These findings suggest that observational studies of habitual coffee intakes are prone to influences by reverse causation, and caution is required when inferred health benefits result from comparisons with coffee abstainers or decaffeinated coffee drinkers,” the authors said.