Is the effect of alcohol on risk of stroke confined to highly stressed persons?
BACKGROUND
Psychological stress and alcohol are both suggested as risk factors for stroke. Further, there appears to be a close relation between stress and alcohol consumption. Several experimental studies have found alcohol consumption to reduce the immediate effects of stress in a laboratory setting. We aimed to examine whether the association between alcohol and stroke depends on level of self-reported stress in a large prospective cohort.


METHODS
The 5,373 men and 6,723 women participating in the second examination of the Copenhagen City Heart Study in 1981-1983 were asked at baseline about their self-reported level of stress and their weekly alcohol consumption. The participants were followed-up until 31st of December 1997 during which 880 first ever stroke events occurred. Data were analysed by means of Cox regression modelling.


RESULTS
At a high stress level, weekly total consumption of 1-14 units of alcohol compared with no consumption seemed associated with a lower risk of stroke (adjusted RR: 0.57, 95% CI: 0.31-1.07). At lower stress levels, no clear associations were observed. Regarding subtypes, self-reported stress appeared only to modify the association between alcohol intake and ischaemic stroke events. Regarding specific types of alcoholic beverages, self-reported stress only modified the associations for intake of beer and wine.


CONCLUSIONS
This study indicates that the apparent lower risk of stroke associated with moderate alcohol consumption is confined to a group of highly stressed persons. It is suggested that alcohol consumption may play a role in reducing the risk of stroke by modifying the physiological or psychological stress response.
Nielsen
N R
NR
Centre for Alcohol Research, National Institute of Public Health, Copenhagen, Denmark. nrn@niph.dk
Truelsen
T
T
Barefoot
J C
JC
Johnsen
S P
SP
Overvad
K
K
Boysen
G
G
Schnohr
P
P
Grønbaek
M
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking / Q000523:psychology*; D000434:Alcoholic Beverages / Q000009:adverse effects*; D003718:Denmark; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D012647:Self-Assessment; D013315:Stress, Psychological / Q000523:psychology*; D020521:Stroke / Q000209:etiology*