Transient exposure to coffee as a trigger of a first nonfatal myocardial infarction.
BACKGROUND
The effects of coffee on myocardial infarction are uncertain. We hypothesize that coffee in the presence of predisposing factors can induce a cascade of events that, through sympathetic nervous activation, can induce the onset of myocardial infarction.


METHODS
We recruited 503 incident cases of nonfatal myocardial infarction between 1994 and 1998 in Costa Rica. We used a case-crossover design to calculate relative risks (RRs) and 95% confidence intervals (95% CIs).


RESULTS
The RR of myocardial infarction in the hour after coffee intake was 1.49 (95% CI = 1.17-1.89). Occasional coffee drinkers (< or =1 cup/day, n = 103) had a RR of myocardial infarction of 4.14 (2.03-8.42), moderate coffee drinkers (2-3 cups/day, n = 280) had a RR of 1.60 (1.16-2.21), and heavy coffee drinkers (> or =4 cups/d, n = 120) had a RR of 1.06 (0.69-1.63; P = 0.006, test of homogeneity). Patients with 3 or more risk factors (n = 101) had a RR of myocardial infarction of 2.10 (1.30-3.39), whereas patients with fewer than 3 risk factors (n = 396) had a RR of 1.39 (1.04-1.82; P = 0.15, test of homogeneity); and RR was 1.72 (1.30-2.30) among sedentary patients compared with 1.07 (0.66-1.72) among nonsedentary (P = 0.10, test of homogeneity).


CONCLUSIONS
The findings indicate that coffee intake may trigger myocardial infarction. The association is particularly strong among people with light/occasional intake of coffee (< or =1 cup/day), with sedentary lifestyle, or with 3 or more risk factors for coronary heart disease.
Baylin
Ana
A
Department of Community Health, Brown University, Providence, RI 02912, USA. Ana_Baylin@btrown.edu
Hernandez-Diaz
Sonia
S
Kabagambe
Edmond K
EK
Siles
Xinia
X
Campos
Hannia
H
D000208:Acute Disease; D000368:Aged; D002110:Caffeine / Q000009:adverse effects*; D000697:Central Nervous System Stimulants / Q000009:adverse effects*; D003069:Coffee / Q000009:adverse effects*; D003364:Costa Rica / Q000453:epidemiology; D018592:Cross-Over Studies; D005247:Feeding Behavior / Q000502:physiology; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000139:chemically induced / Q000453:epidemiology*; D012306:Risk; D011795:Surveys and Questionnaires
D000697:Central Nervous System Stimulants; D003069:Coffee; D002110:Caffeine