Coffee and Alcohol Affect Blood Pressure

In a press briefing, the American Society of Hypertension (ASH) revealed evidence that coffee and alcohol consumption can affect blood pressure (BP) levels. Several studies, which will be presented at the organization’s 26th Annual Scientific Meeting and Exposition, examine the role of caffeine and alcohol consumption on BP. According to ASH, the findings will help physicians treat patients more effectively.

“It’s critical that we fully understand how lifestyle factors impact the ability of patients and physicians to screen, diagnosis, and treat high blood pressure," explains ASH press briefing moderator Lawrence J. Appel, MD, MPH, Professor of Medicine, Epidemiology and International Health (Human Nutrition) Director, Welch Center for Prevention, Epidemiology, and Clinical Research Johns Hopkins Medical Institutions. “As we continue to develop our understanding of how diet and exercise choices impact hypertension, including the nuances among specific patient populations, we are gathering evidence to help us best counsel and advise our patients."

One new meta-analysis shows that, among hypertensive individuals, caffeine intake of 1.5 to 2 cups of coffee produces an acute increase in BP, which lasts for at least three hours. However, evidence does not support an association between longer-term coffee consumption and increased BP or increased risk of cardiovascular disease among patients with HBP.

“These results have clinical implications for the control of hypertensive patients. Because caffeine intake acutely increases blood pressure, hypertensive patients with uncontrolled blood pressure should avoid consuming large doses of caffeine. Also, the consumption of caffeine in the hours before measuring blood pressure may elevate the reading and give the erroneous impression that blood pressure is poorly controlled," explains lead study author, Esther Lopez-Garcia, PhD, Department of Preventive Medicine and Public Health, Autonoma University of Madrid, Spain. “Finally, in well-controlled hypertensive patients, there is no evidence to justify avoidance of habitual caffeine consumption and healthcare providers should emphasize other lifestyle modifications, such as maintaining weight control, increasing physical activity, and stopping smoking."

In a study on the link between alcohol consumption and hypertension, researchers found that, in men, drinking too much alcohol can raise BP to unhealthy levels. The meta-analysis evaluated a total of 16 prospective studies, which included 158,142 men and 314,258 women. Among men, a linear dose–response relationship between alcohol intake and risk of development of hypertension was noted. As compared to non-drinkers, men consuming more than 10 grams of alcohol per day had a relative risk (RR) of 1.006, those consuming 10-20 grams per day had a RR of 1.091, and those consuming more than 30 grams per day had a RR of 1.416. Among women, the meta-analysis indicated protective effects at less than 10grams per day (RR -0.867) and 10-20 grams per day (RR – 0.904) of alcohol consumption, while the risk increased in women consuming more than 30 grams per day (RR – 1.188). The risk of hypertension significantly increases with consumption of more than 30 grams per day in men in women alike.

“For patients, especially men, it’s very important to ask about alcohol consumption and to recommend moderation when trying to maintain blood pressure control," explains Agarwal, MD, MPH, Department of Medicine, St. Luke’s-Roosevelt Hospital, Columbia University College of Physicians and Surgeons.