Early detection of arterial stiffness is useful in primary and secondary prevention of a series of major CVD like coronary artery disease and hypertension. Several studies have shown that PWV was an independent predictor of future development of CVD [12, 13]. The baPWV measurement is noninvasive and convenient, and has been used for cardiovascular risk stratification . For the first time, the present study investigated the prevalence of arterial stiffness in North China on the basis of a 23-community-based study population, and explored the association between high baPWV and CVD risk factors based on general population other than highly characteristic cohorts. Also, the age-specific cut-off points of baPWV were determined and evaluated in terms of its associations with increased arterial stiffness defined by high baPWV in male and female northern Chinese population.
The present data indicated that males had a higher average and upper limit baPWV values than females. In the healthy reference aged 50–59 years, women had a higher age-specific cut-off value of arterial stiffness than men did. Previous researches have indicated that estrogen have beneficial effects on arterial stiffness. A Japanese study reported that the menopause augments the age-related increase in arterial stiffness during the early postmenopausal phase and that this augmentation is probably related, at least in part, to estrogen deficiency . Also, Sztejnsznajd and et al. claimed that long-term administration of oral estrogens leads to an improvement in arterial distensibility in postmenopausal women . The mean age of natural menopause in China was 48.7 years according to a recent study . Therefore, we may infer that decrease of estrogen in menopause might take effect on the arterial stiffness.
The male participants in 50–59 years age group had the greatest prevalence of arterial stiffness, while it was the case in 60–69 years age group of female participants. Considering that arterial stiffness had been associated with the risk of CVD, the present result may suggest that the burden of CVD associated to arterial stiffness rise to the greatest extent in middle-age population. It should be pointed out that, were the cut-off points for high PWV defined irrespectively of age group, the prevalence of “high baPWV” would have gone up sharply with increasing age in both genders. However, results in this circumstance would be invalid due to the confounding effects of age. Two recent studies showed that higher baPWV was associated with an increased risk total mortality [18, 19], and inferred that healthiest people with lower baPWV are more likely to survive past 60 years. This might contribute to a greater prevalence of high baPWV in middle-aged group. Follow-up of the present study is expected to further the interpretation.
In this study, the identified potential risk factors of arterial stiffness based on baPWV measurement were faster HR, higher SBP, higher fasting glucose level, and smoking in men, while were HR, SBP, TC level, and diabetes in women. Two previous studies observed the presence of increased arterial stiffness in patients with hypertension, dyslipidemia and/or diabetes [20, 21]. The present data suggested that SBP should be an important clinical indicator of increased arterial stiffness both in men and in women.
Smoking is another major risk factor in the development and progression of CVD . This study indicated that it may also be responsible for greater arterial stiffness, especially in men. Alterations in hemostatic factors and injury to the vascular endothelial function may play an important role in increasing arterial stiffness . The reason why no significant association was found between smoking and baPWV in women is probably due to the fact that the small number of female smokers could not yield statistical significance.
The present data showed that the higher HR was significantly associated with the high baPWV in men and in women. HR changes can influence arterial distensibility . An epidemiological study assessed the relationship between HR and PWV and demonstrated that there was a statistically significant positive link between the higher HR and the higher arterial stiffness . It is worth further investigation that whether lowering HR therapy using β-blockers or other methods benefits patients with increased arterial stiffness or not. Obesity is also an established risk factor of CVD and arterial stiffness . However, we found no significant relation between BMI and baPWV in multivariable models. This is partly due to the low prevalence of obesity in the population, which limits power to detect a relation.
The strength of this study is a multi-community-based general population with the large sample size, which makes it possible to stratify subjects by age group, and results generalizable to individuals in different ages. However, the present study has limitations. Firstly, response rate was 53.6%. A low response rate may give rise to sampling bias if the nonresponse is unequal among the participants regarding exposure and/or outcome. Though the most common reason was refusal of examinations, it was unclear that whether other reasons not to participate related to factors associated with arterial stiffness. Secondly, the present study did not examine markers of inflammation and renal function, and therefore, could not evaluate this particular relationship. Besides, the limitation of the cross-sectional design was also a fact in this study. The prognostic significance of the baPWV could not be evaluated. Finally, the population was from North China, and may not suitable applied for south areas of China and other countries. Longitudinal studies with a large sample size and a follow-up of the present study are expected to further explore these questions.