Background Studies on coronary risk factors in men and women are
mainly based on mortality data and few compare results of both sexes with
consistent study design and diagnostic criteria. This study assesses the major
risk factors for coronary events in men and women from the Reykjavik Study.
Design Within a prospective, population-based cohort study
individuals without history of myocardial infarction were identified and the
relative risk of baseline variables was assessed in relation to verified
myocardial infarction or coronary death during follow-up.
Methods Of the 9681 women and 8888 men who attended risk assessment
from 1967–1991, with follow-up period of up to 28 years, 706 women
and 1700 men suffered a non-fatal myocardial infarction or coronary death.
Results Serum cholesterol was a significant risk factor for both
sexes, with hazard ratios (HR) decreasing with age. Systolic blood pressure was
a stronger risk factor for women as was ECG-confirmed left ventricular
hypertrophy (women HR 2.89, 95% confidence interval [CI]
1.67–5.01; men HR 1.11 [CI 0.86–1.43]). Fasting blood
glucose ≥6.7 mmol/L identified significantly higher risk for women
(HR 2.65) than men (HR 2.08) as did self-reported diabetes. Triglyceride risk
was significantly higher for women and decreased significantly with age. Smoking
increased risk two- to five-fold, increasing with dose, for women, which was
significantly higher than the doubling in risk for men.
Conclusions This large study of the major risk factors compared
between the sexes demonstrates similar relative risk of myocardial infarction
associated with cholesterol for both sexes, however, the relative risk is higher
in women for many other risk factors such as smoking, diabetes, elevated
triglycerides and left ventricular hypertrophy.
Barrett-ConnorE.Sex differences in coronary heart disease. Why are women so
superior? The 1995 Ancel Keys Lecture.
Circulation1997;
95:252–264.
2.
WexlerLF.Studies of acute coronary syndromes in women: Lessons for
everyone. N Engl J Med1999;
341:275–276.
3.
VaccarinoVParsonsLEveryNRBarronHVKrumholzHM.Sex-based differences in early mortality after myocardial
infarction. N Engl J Med1999;
341:217–225.
4.
HochmanJSTamisJEThompsonTDWeaverWDWhiteHDVan De WerfFSex, clinical presentation, and outcome in patients with acute
coronary syndromes. N Engl J Med1999;
341:226–232.
5.
Tunstall-PedoeHKuulasmaaKAmouyelPArveilerDRajakangasAPajakA.Myocardial infarction and coronary deaths in the World Health
Organization MONICA project. Circulation1994;
90:583–612.
6.
SorliePDCooperLSchreinerPJRosamondWSzkloM.Repeatability, and validity of the Rose questionnaire for angina
pectoris in the Atherosclerosis Risk in Communities Study.
J Clin Epidemiol1996;
49:719–725.
7.
JonsdottirLSSigfussonNSigvaldasonHThorgeirssonG.Incidence, and prevalence of recognised and unrecognised
myocardial infarction in women. The Reykjavik Study.
Eur Heart J1998;
19:1011–1018.
8.
RoseGMcCartneyPReidDD.Self-administration of questionnaire on chest pain and
intermittent claudication. Brit J Soc Med1977;
31:42–48.
9.
RoseGABlackburnH.Cardiovascular survey methods,
Geneva: World Health
Organization, 1968.
10.
BjörnssonOJDavidssonDOlafssonOSigfussonNThorsteinssonT.Survey of serum lipid levels in Icelandic men aged
34–61 years. An epidemiological and statistical
evaluation. Acta Med Scand1977; 203 (Suppl
616):1–150.
11.
SigfussonNSigvaldasonHSteingrimsdottirLGuđmundsdottirIIStefansdottirIThorsteinnTDecline in ischaemic heart disease in Iceland and change in risk
factor levels. Brit Med J1991;
302:1371–1375.
12.
SigfussonN.Hypertension in middle-aged men. The effect of repeated screening
and referral to community physicians on hypertension
control. Acta Med Scand1986; 220 (Suppl
710):1–131.
13.
World Health Organization Study Group on
Prevention of Diabetes Mellitus.Prevention of diabetes mellitus.
Technical report series 844, World Health
Organization, Geneva,
1994.
14.
SigurdssonGGottskalkssonGThorsteinssonTDavidsonDOlafssonOSamuelssonSCommunity screening for glucose intolerance in middle-aged
Icelandic men. Deterioration to diabetes over a period of 7.5
years. Acta Med Scand1981;
210:21–26.
15.
GebskyVLeungOMcNeilDLunnD.SPIDA User's Manual, version 6, New
South Wales, Australia; Statistical
Computing Laboratory MacQuarie University;
1992.
16.
TuliniusHSigfussonNSigvaldasonHBjarnadottirKTryggvadottirL.Risk factors for malignant diseases: A cohort study on a
population of 22,946 Icelanders. Cancer Epidemiol
Biomarkers Prev1997;
6:863–873.
17.
LernerDJKannelWB.Patterns of coronary heart disease morbidity and mortality in the
sexes: A 26-year follow-up of the Framingham population.
Am Heart J1986;
111:383–390.
18.
VilbergssonSSigurdssonGSigvaldasonHSigfussonN.Coronary heart disease mortality amongst non-insulin dependent
diabetic subjects in Iceland: The independent effect of diabetes. The
Reykjavik Study 17-year follow-up. J Intern Med1998;
244:309–316.
19.
ElíassonJHTryggvadóttirLTuliniusHGuđmundssonJA.Hormone replacement therapy in Iceland.
Icelandic Medical Journal
(Læknablađiđ)1998; 84:
25–31 (In Icelandic, English abstract
and figures).
20.
VartiainenEJousilahtiPPekkanenJTuomilehtoJPuskaP.Predicting ischemic heart disease mortality with the classical
risk factors. In: PuskaPTuomilehtoJNissinenA, eds. The North Karelia Project: 20-year results and
experiences. Helsinki,
Helsinki University Printing House1995; 233–240.
21.
StamlerJDyerARShekelleRBNeatonJStamlerR.Relationship of baseline major risk factors to coronary and
all-cause mortality and to longevity: Findings from long-term follow-up of
Chicago cohorts. Cardiology1993;
82:191–222.
22.
PsatyBMFurbergCDKullerLHBildDERautaharjuPMPolakJFTraditional risk factors and sub-clinical disease measures as
predictors of first myocardial infarction in older adults. The
Cardiovascular Study. Arch Intern Med1999;
159:1339–1347.
23.
Medical Research Council Working Party.MRC trial of treatment of mild hypertension: Principal
results. BMJ1985;
291:97–104.
24.
KitlerME.Differences in men and women in coronary artery disease, systemic
hypertension, and their treatment. Am J Cardiol1992;
70:1077–1080.
25.
AnastosKCharneyPCharonRACohenEJonesCYMarteCHypertension in women: What is really
known?. Ann Intern Med1991;
115:287–293.
26.
ChambersJ.Left ventricular hypertrophy. An under-appreciated coronary risk
factor. BMJ1995;
311:273–274.
27.
KannelWBAbbottRD.A prognostic comparison of asymptomatic left ventricular
hypertrophy and unrecognised myocardial infarction: The Framingham
Study. Am Heart J1986;
111:391–397.
28.
De BacquerDMartinsPereira LSDe BackerGDe HenauwSKornitzerM.The predictive value of electrocardiographic abnormalities for
total and cardiovascular disease mortality in men and women.
Eur Heart J1994;
15:1604–1610.
29.
LaRosaJCHunninghakeDBushDCriquiMHGetzGSGottoAMThe cholesterol facts. A summary of the evidence relating dietary
fats, serum cholesterol, and coronary heart disease.
Circulation1990;
81:1721–1733.
30.
CastelliWP.Lipids, risk factors, and ischaemic heart
disease. Atherosclerosis1996;
124:S1–S9.
31.
ShipleyMJPocockSJMarmotMG.Does plasma cholesterol concentration predict mortality from
coronary heart disease in elderly people? 18-year follow-up in
Whitehall study. BMJ1991;
303:89–92.
32.
HowardGManolioTABurkeGLWolfsonSKO'LearyDH.Does the association of risk factors and atherosclerosis change
with age? Stroke1997;
28:1693–1701.
33.
AustinMAHokansonJEEdwardsKL.Hypertriglyceridemia as a cardiovascular risk
factor. Am J Cardiol1998;
81:7B–12B.
34.
GottoAM.JrTriglyceride as a risk factor for coronary artery
disease. Am J Cardiol1998;
82:22Q–25Q.
35.
BellDSH.Diabetes mellitus and coronary artery disease.
Coron Artery Dis1996;
7:715–722.
36.
Barrett-ConnorELCohnBAWingardDLEdelsteinSL.Why is diabetes mellitus a stronger risk factor for fatal
ischemic heart disease in women than in men? The Rancho Bernardo
Study. JAMA1991;
265:627–631.
37.
NjölstadIArnesenELund-LarsenPG.Smoking, serum lipids, blood pressure, and sex differences in
myocardial infarction. A 12-year follow-up of the Finnmark
Study. Circulation1996;
93:450–456.
38.
WillettWCGreenAStampferMJSpeizerFEColditzGARosnerBRelative and absolute excess risk of coronary heart disease among
women who smoke cigarettes. N Engl J Med1987;
317:1303–1309.
