Carotid atherosclerosis is a stronger predictor of myocardial infarction in women than in men: a 6-year follow-up study of 6226 persons: the Tromsø Study.
OBJECTIVE
Ultrasound of carotid arteries provides measures of intima media thickness (IMT) and plaque, both widely used as surrogate measures of cardiovascular disease. Although IMT and plaques are highly intercorrelated, the relationship between carotid plaque and IMT and cardiovascular disease has been conflicting. In this prospective, population-based study, we measured carotid IMT, total plaque area, and plaque echogenicity as predictors for first-ever myocardial infarction (MI).


METHODS
IMT, total plaque area, and plaque echogenicity were measured in 6226 men and women aged 25 to 84 years with no previous MI. The subjects were followed for 6 years and incident MI was registered.


RESULTS
During follow-up, MI occurred in 6.6% of men and 3.0% of women. The adjusted relative risk (RR; 95% CI) between the highest plaque area tertile versus no plaque was 1.56 (1.04 to 2.36) in men and 3.95 (2.16 to 7.19) in women. In women, there was a significant trend toward a higher MI risk with more echolucent plaque. The adjusted RR (95% CI) in the highest versus lowest IMT quartile was 1.73 (0.98 to 3.06) in men and 2.86 (1.07 to 7.65) in women. When we excluded bulb IMT from analyses, IMT did not predict MI in either sex.


CONCLUSIONS
In a general population, carotid plaque area was a stronger predictor of first-ever MI than was IMT. Carotid atherosclerosis was a stronger risk factor for MI in women than in men. In women, the risk of MI increased with plaque echolucency.
Johnsen
Stein Harald
SH
Department of Neurology, University Hospital North-Norway, N-9038 Tromsø, Norway. Stein.Johnsen@ism.uit.no
Mathiesen
Ellisiv B
EB
Joakimsen
Oddmund
O
Stensland
Eva
E
Wilsgaard
Tom
T
Løchen
Maja-Lisa
ML
Njølstad
Inger
I
Arnesen
Egil
E
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002339:Carotid Arteries / Q000000981:diagnostic imaging* / Q000473:pathology*; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000473:pathology; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000473:pathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology; D008076:Cholesterol, HDL; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology*; D009664:Norway / Q000453:epidemiology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D012737:Sex Factors; D017539:Tunica Intima / Q000000981:diagnostic imaging / Q000473:pathology; D014463:Ultrasonography
D008076:Cholesterol, HDL