Pulse wave velocity is decreased with obesity in an elderly Chinese population.

Abstract

Obesity is generally considered an undesirable risk factor for cardiovascular disease; however, obese subjects with heart failure paradoxically can have better outcomes than their lean counterparts. This study aimed to investigate this characteristic in an elderly Chinese population. Elderly participants (N=414, age 77±11years, 211 males) were recruited from a Chinese community-dwelling elderly population. Subjects were divided into 3 groups according to body mass index (BMI≤25, normal; 25-28, overweight; and ≥28, obese). Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV), and the atherosclerosis status was evaluated with the ankle brachial index (ABI). Brachial systolic blood pressure (BSBP) was significantly higher as BMI increased (135±18.4, 138±18.3, 147±17.6mmHg; P=.003) adjusted for age, sex, and heart rate. However, baPWV was significantly lower as BMI increased (baPWV 1830±18, 1793±25, 1704±36cm/s; P=.008) in the three groups, even with additional adjustment for BSBP. BMI showed a significant negative correlation with baPWV (r=-.170, P=.001) after adjusting for confounding factors. Using multiple linear regression, BMI was negatively and independently associated with baPWV (β=-.190, P<.001) especially for age <80years. Arterial stiffness, as measured by baPWV, is lower in overweight subjects in a Chinese elderly population compared to those with normal body weight. ABI showed no relationship with BMI. These findings suggest that reduced arterial stiffness in the overweight population, independent of confounding factors, may contribute to the explanation of the "obesity paradox."