Background: Data on the association between coffee consumption and risk of stroke are sparse. We assessed the association between coffee consumption and the risk of stroke over 24 years of follow-up in women.
Methods and Results: We analyzed data from a prospective cohort of 83,076 women in the Nurses' Health Study without history of stroke, coronary heart disease, diabetes, or cancer at baseline.
Coffee consumption was assessed first in 1980 and then repeatedly every 2 to 4 years, with follow-up through 2004.
We documented 2,280 strokes, of which 426 were hemorrhagic, 1,224 were ischemic, and 630 were undetermined.
In multivariable Cox regression models with adjustment for age, smoking status, body mass index, physical activity, alcohol intake, menopausal status, hormone replacement therapy, aspirin use, and dietary factors, the relative risks (RRs) of stroke across categories of coffee consumption (less than 1 cup per month, 1 per month to 4 per week, 5 to 7 per week, 2 to 3 per day, and 4 or more cups per day) were 1, 0.98 (95% CI, 0.84 to 1.15), 0.88 (95% CI, 0.77 to 1.02), 0.81 (95% CI, 0.70 to 0.95), and 0.80 (95% CI, 0.64 to 0.98) (P for trend=0.003). [Note: A relative risk of 1.0 would mean no difference in stroke incidence from those drinking less than 1 cup a month. An RR of 0.81 for those drinking 2-3 cups a day would mean the average risk of stroke is 19% less than for those drinking less than 1 cup a month, for example.]
After further adjustment for high blood pressure, hypercholesterolemia, and type 2 diabetes, the inverse association remained significant. The association was stronger among never and past smokers (RR for 4 or more cups a day versus <1 cup a month, 0.57; 95% CI, 0.39 to 0.84) than among current smokers (RR for 4 or more cups a day versus <1 cup a month, 0.97; 95% CI, 0.63 to 1.48).
Other drinks containing caffeine such as tea and caffeinated soft drinks were not associated with stroke.
Decaffeinated coffee was associated with a trend toward lower risk of stroke after adjustment for caffeinated coffee consumption (RR for 2 cups a day versus <1 cup a month, 0.89; 95% CI, 0.73 to 1.08; P for trend=0.05).
Conclusions: Long-term coffee consumption was not associated with an increased risk of stroke in women. In contrast, our data suggest that coffee consumption may modestly reduce risk of stroke.
Source: Circulation, Feb 16, 2009. Lopez-Garcia E, Rodriguez-Artalejo F, Rexrode KM, Logroscino G, Hu FB, van Dam RM. Departments of Nutrition and Epidemiology, Harvard School of Public Health, Boston, Mass; Department of Preventive Medicine and Public Health, School of Medicine, Universidad Autonoma de Madrid, Madrid, Spain; CIBER of Epidemiology and Public Health, Barcelona, Spain; Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass; Division of Preventive Medicine, Harvard Medical School, Boston, Mass. [E-mail: firstname.lastname@example.org]