Association of caffeine consumption with all‐cause and cause‐specific mortality in adult Americans with hypertension

Abstract

Coffee is an important beverage that is widely consumed, of which caffeine is the main active ingredient. However, the long‐term relationship between caffeine consumption and mortality in hypertensive patients has rarely been studied. This study analyzed a cohort of 12,093 US adults from the National Health and Nutrition Examination Survey from 1999 to 2018. Caffeine consumption was divided into five groups: no intake, >0 to ≤100, >100 to ≤300, >300 to ≤400 and >400 mg/day. Using multivariable‐adjusted Cox proportional hazards models, this study performed a 20‐year follow‐up analysis (1999–2018). In the fully adjusted model, all caffeine consumers had lower all‐cause mortality compared with no intake, especially in the >300 to ≤400 mg/day group (hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.60–0.84). The result of restricted cubic spline also showed a nonlinear association between caffeine consumption and all‐cause mortality. For cardiovascular disease, mortality decreased only at >400 mg/day (HR 0.63, 95% CI 0.47–0.85). For cancer, diabetes, and kidney disease, only >300 to ≤400 mg/day was significantly associated with decreased mortality: (HR 0.60, 95% CI 0.42–0.67), (HR 0.22, 95% CI 0.07–0.75), and (HR 0.32, 95% CI 0.10–0.96), respectively. Lower all‐cause mortality was observed in non‐Hispanic White, African American, population aged 40 or above, and people with a body mass index <25 kg/m2. Our findings indicate a nonlinear association between average caffeine consumption and all‐cause mortality, suggesting that hypertensive patients may benefit from moderate caffeine intake.