Association between Brachial-Ankle Pulse Wave Velocity as a Marker of Arterial Stiffness and Body Mass Index in a Chinese Population

Abstract

Objectives: Arterial stiffness is widely accepted as an important predictor of cardiovascular disease (CVD) development. While obesity is generally associated with increased CVD risk, there is evidence that overweight patients with existing CVD may have better clinical outcomes than their lean counterparts. Our study sought to observe any potential association between brachial−ankle pulse wave velocity (BAPWV), a marker of arterial stiffness related to CVD risk, and Body Mass Index (BMI), a crude and widely used measure of obesity. Methods: Adult individuals (n = 857) assessed for routine CV risk were included and grouped according to their BMI (<25 kg/m2: normal; 25−30 kg/m2: overweight, ≥30 kg/m2: obese). Their anthropometric parameters, brachial cuff pressures, and BAPWV were measured. Results: Brachial pressure was significantly higher as BMI increased. BAPWV showed a positive linear association with systolic (r = 0.66, p < 0.01), mean (r = 0.60, p < 0.01), diastolic (r = 0.51, p < 0.01), and pulse (r = 0.53, p < 0.01) pressures. However, a linear relationship between BMI and BAPWV was only apparent in males aged <50 years (p = 0.01) and in females aged ≥50 years (p < 0.01). In individuals with similar brachial systolic pressure, BAPWV was higher in normal-weight subjects compared to overweight−obese ones. Conclusions: This conflicting finding is attributed to an overestimation of the degree of arterial stiffness as a measure of CVD risk in individuals with a less ‘healthy’ BMI. This suggests that BMI may not the appropriate obesity indicator to assess CV risk. Our finding emphasizes the importance of establishing a non-linear relationship between CVD risk, age, and BMI, taking into account apparent sex differences, to predict future CV events. While this finding may suggest a lower degree of stiffness in large arteries of overweight−obese subjects compared to their normal-weight counterparts, the potential implications for individuals with higher BMI need be explored further.

Keywords: age; arterial stiffness; blood pressure; body mass index; cardiovascular disease; sex.

Figure 1

Relationship between BAPWV and BMI (black open triangles, females; black closed circles, males). The correlation between BAPWV and BMI was significantly stronger in females compared to males.

Figure 2

Relationship between ABI and BMI (black open triangles, females; black closed circles, males). There was a small correlation between ABI and BMI for both males and females.

Figure 3

Relationship between brachial SP and BAPWV between normal-weight (LW = lean weight) (black open circles, females; black closed circles, males) and overweight (OW)/obese (OB) groups (black open triangles, females; black closed triangles, males). A linear relationship (solid line for LW, dashed line for OW + OB) between BMI class and BAPWV was only apparent for males aged ≤50 years (p = 0.01) and females aged >50 years (p < 0.01). The increase in arterial stiffness (measured as baPWV) in the normal group appeared to be greater with similar brachial SP values when these subjects were compared to individuals in the overweight and obese groups.