Patients with especially high blood pressure may want to limit how much coffee they drink

Anyone with severe high blood pressure who drinks more than one cup of coffee per day may double their risk of death from cardiovascular disease (CVD), according to new research published in the Journal of the American Heart Association.[1] The study defined severe high blood pressure as 160/100 mm Hg or higher.

The relationship between drinking coffee and a person’s heart health has been a popular topic among researchers in recent years. One recent study, for example, found that mild to moderate coffee consumption was linked to a lower risk of CVD. A separate study found a potential connection between coffee and coronary heart disease.  

For this latest analysis, a team of specialists from Japan examined data from more than 6,000 men and more than 12,000 women who were originally recruited to participate in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk. All participants were between the ages of 40 and 79 years old at the start of that study and came from one of 45 different Japanese communities. They documented their eating and drinking habits, as well as other details about their lives, using self-administered questionnaires and health examinations.

Overall, after a follow-up period of nearly 19 years, participants with severe high blood pressure who said they drink at least two cups of coffee each day were twice as likely to experience a cardiovascular death than other participants with severe high blood pressure. This same trend was not seen among participants with severe high blood pressure who drink just one cup of coffee per day. Also, drinking green tea was not linked to cardiovascular deaths in any capacity.

”These findings may support the assertion that people with severe high blood pressure should avoid drinking excessive coffee,” senior author Hiroyasu Iso, MD, PhD, MPH, director of the Institute for Global Health Policy Research in Tokyo and professor emeritus at Osaka University, said in a prepared statement. “Because people with severe hypertension are more susceptible to the effects of caffeine, caffeine’s harmful effects may outweigh its protective effects and may increase the risk of death.”

The team did note that its work had certain limitations. Coffee and tea consumption were self-reported by participants, for instance, and blood pressure measurements were not taken “at a single point, which did not account for changes over time.”

Additional information from the American Heart Association on the potential impact of drinking caffeine is available here.

Michael Walter
Michael Walter, Managing Editor

Michael has more than 18 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.

Around the web

Several key trends were evident at the Radiological Society of North America 2024 meeting, including new CT and MR technology and evolving adoption of artificial intelligence.

Ron Blankstein, MD, professor of radiology, Harvard Medical School, explains the use of artificial intelligence to detect heart disease in non-cardiac CT exams.

Eleven medical societies have signed on to a consensus statement aimed at standardizing imaging for suspected cardiovascular infections.