The results of this study demonstrate that associations between obesity-related parameters and high baPWV differed between sexes and age groups. In the 2 age groups of women, WC and WHtR showed positive associations with baPWV; in middle-aged men, BMI and FTI showed positive associations, while FFTI, FFTI/FTI, and RTFFM showed negative associations. The correlation coefficients of WHtR and WC were higher than that of other parameters. WHtR and baPWV in women showed the highest correlation in the binary logistic regression analysis adjusted for covariates. However, previous studies on the association between obesity-related parameters and baPWV, arteriosclerosis, or hypertension have reported conflicting findings. BMI showed the strongest association in adults [18] or only in one sex [10, 17, 18]. However, others have reported results similar to ours [21, 24–28], including a cohort study in which subjects in the highest quartile of WHtR were 4.51 times more likely to have hypertension [29]. A systematic review also found that WHtR was the best parameter for predicting cardiometabolic risk factors, including hypertension [30]. Notably, those results showed a significant association in both sexes while our findings in men were nonsignificant, which is consistent with a previous study [5]. Few studies have examined the relationship between body composition parameters and baPWV, with only one in the last 5 years demonstrating a positive correlation between FFMI and baPWV; nonetheless, this provides evidence for the value of FFMI as a predictor of arteriosclerosis [31].
In the present work, WHtR and WC had similarly modest capacities for predicting baPWV occurrence in men, and BMI had no predictive value. WHtR, WC, and BMI had similar predictive capacities in women of both age groups, whereas WHtR had slightly stronger predictive power in elderly women. Significant sex differences were observed, with lower predictive capacities in men, especially those who were middle-aged. In contrast, BMI or WC was shown to have predictive value for the occurrence of hypertension [17, 32–34]. There were no significant differences in the predictive capacities of WC, BMI, and WHtR between men and women [32]; and the predictive values of BMI, WC, and WHtR were found to differ significantly between men and women [5], with a better performance in the latter [35]. WHtR has also been proposed as the best predictor of baPWV or hypertension [26, 36–38].
The results of studies can vary according to whether the analysis is stratified by age or sex. BMI was shown to be more closely correlated with baPWV in younger subjects than in older ones [10]. Our study population included a large number of subjects aged > 40 years, with those > 60 years constituting the majority. Sex differences can also explain the discrepancies across reports. Because of metabolic adaptations during menopause, women are at greater risk than men for elevation of total and high low-density lipoprotein cholesterol after the age of 50, and are more likely to accumulate visceral fat [21]; thus, various indicators in women could show a strong association with baPWV or hypertension. Additionally, study design, statistical methods, or selection of variables for adjustment can influence the degree of association.
The cutoff values with the best predictive capacity for high baPWV in the present work based on sensitivity and specificity differed from those reported in studies of hypertension in Asian populations; the ranges were 82.70–85.2 for men and 77.5–83.5 for women [17, 32, 33, 36, 37]. The World Health Organization Working Group on Obesity recommends WC cutoff values of 85 cm for men and 80 cm for women, which are lower than those determined here (95.5 and 88.5 cm for middle-aged and elderly men, respectively; and 83.5 and 83.5 cm for middle-aged and elderly women, respectively). Our BMI ranges (23.86–24.01 for men and 24.08–23.57 for women) were similar to those in previous studies (22.65–24.12 for men and 23.53–27.7 for women) [17, 32, 33, 36], and the same was true for WHtR (0.54–0.55 for men and 0.51–0.52 for women in the present study vs 0.47–0.54 and 0.47–0.54, respectively, in previous reports) [17, 25, 32, 33, 36, 37, 39–41]. Notably, values obtained in a study conducted in Spain (WC, 90.5 cm; BMI, 26.6; WHtR, 0.54 for both sexes) [35] were much higher than those in Asian cohorts. Thus, different countries/regions should develop their own WC and WHtR cutoff values based on local epidemiologic status.
This study had several limitations. Firstly, it had a cross-sectional design and did not evaluate changes in the measured parameters. Secondly, the total number of participants was small, particularly the proportion of men aged 40–59. Finally, the results may not be generalizable to populations outside of Anhui.