Sex differences in susceptibility to etiologic factors for peripheral atherosclerosis. Importance of plasma fibrinogen and blood viscosity.

Abstract

Cardiovascular risk factors in men, such as cigarette smoking, hypercholesterolemia, and hypertension, also increase risk in women, but the relative susceptibility to risk factors between the sexes is not established. Our aim was to investigate a wide range of possible etiologic factors in a single population study and identify those that were more strongly related to peripheral atherosclerosis in men or women. We studied personal factors (age and social class), lifestyle factors (smoking, exercise, alcohol intake, and dietary nutrients), and intermediary factors (obesity, diabetes, serum lipids, coagulation, and rheological factors). In the Edinburgh Artery Study in 1988 we measured cardiovascular risk factors in a random population sample of 1592 men and women aged 55 to 74 years. The ankle-brachial pressure index (ABPI), which is inversely related to the degree of peripheral atherosclerosis, was assessed in each subject. Lifetime cigarette smoking was correlated with a lower ABPI equally in men and women (r=-.27, P<.001). Dietary nutrients and alcohol intake were M en have higher rates of morbidity and mortality due to coronary heart disease than do women, although this differential diminishes with age.12 The well-established risk factors in men, such as cigarette smoking, elevated blood pressure, and hypercholesterolemia, also increase risk in women.1 Sex differences exist in the prevalence and distribution of risk factors. 17 In Scotland men smoke more and have higher blood pressures, whereas women have higher mean serum cholesterol levels. 34 However, the relative importance of etiologic factors in increasing the risk of atherosclerotic disease in men and women is not established. Sex differences in the risks of coronary heart disease appear to be related to serum lipids, but the evidence is sparse and conflicting.246 -8 Plasma glucose and fibrinogen have also been implicated. 59 The reduced risks of coronary heart disease in women who take hormone replacement therapy point to the possi- not related differently between the sexes with ABPI. However, recall of strenuous and moderate leisure time exercise during the age range of 35 to 45 years was related more strongly to a higher ABPI in men than in women (P<.05). Plasma fibrinogen, plasma viscosity, and blood viscosity were the only intermediary factors that had stronger univariate correlations with lower ABPI in men than in women. On multivariate analysis, the sex differences persisted for plasma fibrinogen (/ ) <.O5) and blood viscosity (P<.001); high-density lipoprotein cholesterol was related to ABPI in men only (sex difference, P<.1). We conclude that most lifestyle and intermediary factors were not related differently in men and women to peripheral atherosclerosis, but elevations in plasma fibrinogen and blood viscosity were each associated with a greater risk of disease in men. The aim of this study was to determine differences between men and women in the associations of several etiologic factors with peripheral atherosclerosis. MethodsThi...

Relationship of Monocyte Count and Peripheral Arterial Disease

“…45 Higher fibrinogen levels may potentially promote atherosclerosis by increasing platelet adhesion to the subendothelium as well affecting endothelial function. 46,47 Our and previous findings support the role of fibrinogen as an independent marker of generalized atherosclerotic lesions in major arterial beds.…”

Positive Association Between Plasma Fibrinogen Level and Incident Hypertension Among Men

“…7 Several plausible mechanisms could explain an observed association between elevated fibrinogen levels and hypertension, including the relation of fibrinogen to increased viscosity and peripheral vascular resistance, 20,32 hyperinsulinemia and insulin resistance, 33,34 and markers of inflammation. 34 -36 Gender differences in insulinemia and insulin resistance may also explain the observed lack of association among women.…”

“…A cross several studies, plasma fibrinogen is a consistent predictor of cardiovascular disease, 1-3 subclinical atherosclerosis, 4 -6 peripheral vascular disease, 7 and decreased survival. 3 Several 8 -17 but not all 18 -23 previous cross-sectional epidemiological studies reported a positive association between plasma fibrinogen level and elevated blood pressure and/or prevalent hypertension.…”

The Effects of Smoking on Plasma Viscosity and Related Biochemical Parameters

“…Çalışma-mızda plazma viskozite değerleri daha önce yapılan çalışmalara benzer şekilde cinsiyete göre farklılık göstermemiştir. [35][36][37] Carolla ve arkadaşlarının 38 yaptığı çalışmada, bizim sonuçlarımızla benzer bir şekilde, ilerleyen yaşla birlikte plazma viskozitesinin arttığı bildirilmektedir. Laboratuvar sonuçlarımızda ortalama hemoglobin ve hematokrit düzeyleri erkeklerde, fibrinojen değeri ise kadınlarda daha yüksek bulunmuştur.…”

“…Fibrinojen düze-yinin kadınlarda daha yüksek olduğunu gösteren başka çalışma-lar da vardır. 35,39 Çalışmamızda fibrinojen düzeyi ile yaş arasın-da Onat ve arkadaşlarının çalışmasına benzer şekilde pozitif bir korelasyon saptandı. 39 Yine yaş ve VKİ artışı ile fibrinojen, total kolesterol ve trigliserid düzeylerinde önceki çalışmalara benzer şekilde istatistiksel olarak anlamlı bir artış bulundu.…”