Homocysteine and cerebral infarction in finnish male smokers.
OBJECTIVE
Homocysteine is associated with stroke, but it is not clear whether this relationship is causal. We examined the association between total serum homocysteine concentration (tHcy) and cerebral infarction in a cohort of Finnish male smokers.


METHODS
This is a matched case-control study of 201 cases of cerebral infarction and 201 concurrently sampled age-matched controls nested in a cohort of 13 840 male smokers free of cardiovascular disease at the completion of the Alpha-Tocopherol and Beta-Carotene (ATBC) Cancer Prevention study. Conditional logistic regression was used to calculate odds ratios (ORs) and to adjust for confounding variables. An unmatched analysis was also performed.


RESULTS
The geometric mean tHcy was 13.3 micromol/L (95% CI, 12.6 to 13.9) in cases and 12.6 micromol/L (95% CI, 12.0 to 13.2) in controls (P=0.09). There was a graded increase in the OR of cerebral infarction per quartile increase in tHcy (OR, 1.0, 1.7, 1.9, 2.1; trend P=0.02; 201 case-control pairs) when adjusted for traditional risk factors. There was a similar trend in a subgroup of 120 case-control pairs for which further adjustment for lifestyle factors was possible (OR, 1.0, 1.9, 2.5, 2.2; trend P=0.07 in the matched analyses; OR, 1.0, 1.2, 1.9, 2.0; trend P=0.02 in the unmatched analyses). The adjusted OR per 1-SD increase in log-transformed tHcy (equivalent to 4.7 micromol) was 1.4 (95% CI, 1.1 to 1.7; P=0.01).


CONCLUSIONS
tHcy appears to predict cerebral infarction in Finnish male smokers.
Fallon
Una B
UB
Department of Social Medicine, University of Bristol, Canynge Hall, Whiteladies Rd, Bristol BS8 2PR, UK. una.fallon@bristol.ac.uk
Virtamo
Jarmo
J
Young
Ian
I
McMaster
Dorothy
D
Ben-Shlomo
Yoav
Y
Wood
Nigel
N
Whitehead
Alexander S
AS
Smith
George Davey
GD
D000368:Aged; D001794:Blood Pressure; D016022:Case-Control Studies; D002544:Cerebral Infarction / Q000097:blood* / Q000453:epidemiology; D015331:Cohort Studies; D015986:Confounding Factors, Epidemiologic; D005387:Finland / Q000453:epidemiology; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008019:Life Style; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D018570:Risk Assessment; D012307:Risk Factors; D012907:Smoking / Q000097:blood* / Q000453:epidemiology; D025101:Vitamin B 6 / Q000097:blood
D006710:Homocysteine; D025101:Vitamin B 6; D005492:Folic Acid