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liveonearth ([personal profile] liveonearth) wrote2012-05-22 02:45 pm

Coffee decreases mortality unless you have cancer

This study had a sample size of nearly 400,000 adults and lasted for 13 years. They had to adjust the findings for cigarette smoking, which is of course prevalent among coffee drinkers.

THE STUDY
Association of Coffee Drinking with Total and Cause-Specific Mortality
N Engl J Med. 2012;366:1891-1904
largest study to date, 13 years in duration (1995 - 2008)
n=229,119 men and 173,141 women in National Institutes of Health–AARP Diet and Health Study
ages at baseline 50-71 years
excluded pts c cancer, CV dz, hx of stroke
May 2012 issue of the New England Journal of Medicine. Neal Freedman, PhD.
finding: coffee consumption inversely assoc c total and cause-specific mortality
confounder: smoking. adjust for that and you get result given.
coffee preparation: not considered

Men
2-6 cups/day-->10% decrease in mortality
Women
2 to 3 cups-->13% decrease in mortality
6 cups-->15%

CV DZ
coffee increases LDL and BP
theoretical: coffee may increase the risk of heart disease
not substantiated by science so far

CAUSE SPECIFIC MORTALITY
inverse associations for deaths resulting from CV dz, CVA, DM, Resp dz, infx, injury, accident, but NOT cancer.

CANCER
"there was no significant association between coffee consumption and deaths from cancer in women" borderline positive association in men

ABSTRACT
http://www.nejm.org/doi/full/10.1056/NEJMoa1112010

METHODS
We examined the association of coffee drinking with subsequent total and cause-specific mortality among 229,119 men and 173,141 women in the National Institutes of Health–AARP Diet and Health Study who were 50 to 71 years of age at baseline. Participants with cancer, heart disease, and stroke were excluded. Coffee consumption was assessed once at baseline.

RESULTS
During 5,148,760 person-years of follow-up between 1995 and 2008, a total of 33,731 men and 18,784 women died. In age-adjusted models, the risk of death was increased among coffee drinkers. However, coffee drinkers were also more likely to smoke, and, after adjustment for tobacco-smoking status and other potential confounders, there was a significant inverse association between coffee consumption and mortality. Adjusted hazard ratios for death among men who drank coffee as compared with those who did not were as follows: 0.99 (95% confidence interval [CI], 0.95 to 1.04) for drinking less than 1 cup per day, 0.94 (95% CI, 0.90 to 0.99) for 1 cup, 0.90 (95% CI, 0.86 to 0.93) for 2 or 3 cups, 0.88 (95% CI, 0.84 to 0.93) for 4 or 5 cups, and 0.90 (95% CI, 0.85 to 0.96) for 6 or more cups of coffee per day (P<0.001 for trend); the respective hazard ratios among women were 1.01 (95% CI, 0.96 to 1.07), 0.95 (95% CI, 0.90 to 1.01), 0.87 (95% CI, 0.83 to 0.92), 0.84 (95% CI, 0.79 to 0.90), and 0.85 (95% CI, 0.78 to 0.93) (P<0.001 for trend). Inverse associations were observed for deaths due to heart disease, respiratory disease, stroke, injuries and accidents, diabetes, and infections, but not for deaths due to cancer. Results were similar in subgroups, including persons who had never smoked and persons who reported very good to excellent health at baseline.

CONCLUSIONS
In this large prospective study, coffee consumption was inversely associated with total and cause-specific mortality. Whether this was a causal or associational finding cannot be determined from our data. (Funded by the Intramural Research Program of the National Institutes of Health, National Cancer Institute, Division of Cancer Epidemiology and Genetics.)