The association between circulating white blood cell count, triglyceride level and cardiovascular and all-cause mortality: Population-based cohort study
Introduction
The pathogenesis of cardiovascular disease is multifactorial and involves interactions between genetic and various traditional and non-traditional environmental factors [1], [2]. Increasing evidence supports a role for inflammation in the atherosclerotic process [3]. Several prospective studies have shown that elevated circulating white blood cell (WBC) count, a widely available marker of systemic inflammation, is related to cardiovascular disease (CVD) and mortality, independent of the traditional risk factors [4], [5], [6], [7], [8], [9], [10], [11], [12]. To our knowledge, the relationship between WBC count and cardiovascular mortality has not been examined in a population-based study from Australia.
Triglyceride levels are related to markers of inflammation [13], [14]. Elevated triglyceride levels are found to be independently predictive of CVD in some [15], [16], [17], but not all studies [18], [19], [20]. The relationship between elevated WBC count, triglyceride levels and their relationship to CVD has not been compared simultaneously in a population-based study before.
We examined the relationship between WBC count, triglyceride levels and cardiovascular and all-cause mortality in an older Australian population, after adjusting for several main confounding variables.
Section snippets
Study population
The Blue Mountains Eye Study (BMES) is a population-based cohort study of age-related eye diseases and other health outcomes in an urban Australian population. Study details were described previously [21]. After a door-to-door census of residents living in two postcodes in the Blue Mountains region, west of Sydney, Australia, persons born before 1 January 1943, were invited to attend a detailed examination at a local hospital. Baseline examination was performed on 3654 of 4433 (82.4%) eligible
Results
Baseline characteristics of the cohort according to WBC count quartiles are shown in Table 1. Individuals with higher WBC count were more likely to be male, current smokers, physically inactive, have higher hematocrit, BMI, more likely to have diabetes, higher systolic blood pressure, total cholesterol and triglyceride level, lower HDL-C level, and less likely to have self-rated health as “excellent”.
There were 242 cardiovascular (n = 179 ischemic heart disease, n = 63 stroke) deaths and 575
Discussion
In the Blue Mountains cohort of older Australians, we found that elevated WBC count was associated with cardiovascular and all-cause mortality, independent of smoking, diabetes, hypertension, lipid levels and other related factors. Compared to individuals in the first quartile (4.8 × 109 cells/L and below), individuals in the fourth quartile (6.8 × 109 cells/L and above) of WBC count had over two-fold risk of cardiovascular mortality. Plasma triglyceride levels were also found to be independently
References (32)
- et al.
White blood cell count: an independent predictor of coronary heart disease mortality among a national cohort
J Clin Epidemiol
(2001) - et al.
Leukocytes as a coronary risk factor in a dyslipidemic male population
Am Heart J
(1992) - et al.
Visual acuity and the causes of visual loss in Australia. The Blue Mountains Eye Study
Ophthalmology
(1996) - et al.
Prevalence of age-related maculopathy in Australia. The Blue Mountains Eye Study
Ophthalmology
(1995) - et al.
Accuracy of the Australian National Death Index: comparison with adjudicated fatal outcomes among Australian participants in the Long-term Intervention with Pravastatin in Ischaemic Disease (LIPID) study
Aust N Z J Public Health
(2003) - et al.
Effectiveness of the National Death Index for establishing the vital status of older women in the Australian Longitudinal Study on Women's Health
Aust N Z J Public Health
(2000) - et al.
Relation between insulin resistance and hematological parameters in elderly Koreans-Southwest Seoul (SWS) Study
Diabetes Res Clin Pract
(2003) - et al.
Postprandial leukocyte increase in healthy subjects
Metabolism
(2003) - et al.
Future of biomarkers in acute coronary syndromes: moving toward a multimarker strategy
Circulation
(2003) - et al.
Gene: environment interactions and coronary heart disease risk
World Rev Nutr Diet
(2004)