Increased coffee intake was linked to a reduced risk of developing heart failure and stroke later in life, according to an analysis of 3 large epidemiologic studies published in Circulation: Heart Failure.1 In one of those studies – the Framingham Heart Study (FHS) – each extra cup of coffee per day reduced the risk of heart failure by 5% and stroke by 6%.1
Senior author David P. Kao, MD, called the findings “surprising” given that coffee and caffeine have been linked to palpitations and high blood pressure.2 Dr. Kao is assistant professor of medicine in the Divisions of Cardiology and Biomedical Informatics/Personalized Medicine at the University of Colorado School of Medicine and is medical director of the Colorado Center for Personalized Medicine.
“The consistent relationship between increasing caffeine consumption and decreasing heart failure risk turns that assumption on its head,” Dr Kao said in a news release.2 “However, there is not yet enough clear evidence to recommend increasing coffee consumption to decrease the risk of heart disease with the same strength and certainty as stopping smoking, losing weight, or exercising.”
Additionally, “this analysis suggests that there is no reason to decrease coffee consumption on purpose for the sake of your heart health,” Dr. Kao told Clinician Advisor in an interview.
Study Rationale and Design
While there are many well-known risk factors for heart failure and cardiovascular disease, many unidentified risk factors remain. The objective of this study was to use machine learning to identify other potential risk factors for incident coronary heart disease, stroke, and heart failure using data from the FHS in a “hypothesis-free, data-driven manner,” according to the researchers.
The significance of associations between identified variables and cardiovascular disease were adjusted for known risk factors and were validated using data from the Atherosclerosis Risk in Communities (ARIC) study and Cardiovascular Health Study (CHS) — the other 2 studies used in the analysis. Each study included at least 10 years of follow-up, and provided data on more than 21,000 US adults in total.
Coffee Correlated With Heart Failure Risk
As expected, the analysis confirmed well-known risk factors including high blood pressure, high cholesterol, marital status, and smoking. Of the dietary factors identified as among the top 20% of variables selected for further evaluation (including whole milk, eggs, alcohol, cheese, coffee, and decaffeinated coffee), only increasing caffeinated coffee consumption remained significantly associated with reduced long-term risk of heart failure in the FHS with a hazard ratio (HR) of 0.95 per cup per day (95% CI, 0.91-0.99; P =.02).
The link between coffee intake and heart failure risk was validated in the ARIC study and CHS. The mechanisms behind these associations are unclear, the study authors noted.
A dose-response analysis (Figure) using all 3 studies found that the risk of heart failure was similar among participants drinking 0 or 1 cup per day, but decreased significantly in those who drank 2 cups per day (HR, 0.69 [95% CI, 0.55–0.87]; P <.001) and ≥3 cups/day (HR, 0.71 [95% CI, 0.58–0.89]; P <.001) compared with no coffee consumption.
Coffee consumption also was linked to a reduced risk of stroke (HR, 0.94 per cup/day [95% CI, 0.89-0.99]; P =0.02) but not coronary heart disease or cardiovascular disease (P =.21 and .59, respectively).
Decaffeinated Coffee Associated With Increased Heart Failure Risk
Decaffeinated coffee intake, on the other hand, was linked to a significantly increased risk of heart failure in the FHS (HR, 1.10 per cup/day [95% CI, 1.03-1.17]; P =.004) but not in CHS study (P =.63). Data on decaffeinated coffee from ARIC study was not included in this study.
The correlation between coffee and heart failure does not establish causality, the researchers noted. The findings also conflict with those of a prospective study of 20,433 middle-aged and older men enrolled in the Physicians’ Health Study, which found no association between coffee consumption or dietary caffeine intake and heart failure risk.3
Study limitations include the observational and retrospective nature of the data, reliance on patient self-report of coffee intake, and the inability to distinguish between the type of coffee consumed (drip vs espresso), use of sugar and cream or other additives, brewing method (filtered vs unfiltered), and time of consumption (morning vs evening), which could affect the association between coffee and clinical outcomes, according to the study authors.
Take Your Coffee Black
“While unable to prove causality, it is intriguing that these 3 studies suggest that drinking coffee is associated with a decreased risk of heart failure and that coffee can be part of a healthy dietary pattern if consumed plain, without added sugar and high-fat dairy products such as cream,” commented Penny M. Kris-Etherton, PhD, RDN, immediate past chairperson of the American Heart Association’s Lifestyle and Cardiometabolic Health Council Leadership Committee in a news release.2
However, because caffeine is a stimulant, consuming too much may cause jitteriness and sleep problems, added Dr Kris-Etherton, who is also Evan Pugh University Professor of Nutritional Sciences, and distinguished professor of nutrition at The Pennsylvania State University, College of Health and Human Development in University Park.
1. Stevens LM, Linstead E, Hall JL, Kao DP. Association between coffee intake and incident heart failure risk: a machine learning analysis of the FHS, the ARIC Study, and the CHS. Circ Heart Fail. 2021;14(2):e006799. doi:10.1161/CIRCHEARTFAILURE.119.006799
2. Coffee lovers, rejoice! Drinking more coffee associated with decreased heart failure risk. News Release. American Heart Association. February 09, 2021. Accessed February 23, 2021. https://newsroom.heart.org/news/coffee-lovers-rejoice-drinking-more-coffee-associated-with-decreased-heart-failure-risk
3. Bodar V, Chen J, Sesso HD, Gaziano JM, Djoussé L. Coffee consumption and risk of heart failure in the Physicians’ Health Study. Clin Nutr ESPEN. 2020;40:133-137. doi:10.1016/j.clnesp.2020.09.216