Correlation between body mass index and change in inter-arm diastolic pressure difference after transient right arm ischemia in young male students

Objective  To evaluate the relationship of inter-arm diastolic pressure difference (d-IAD) after right arm ischemia with body mass index (BMI) in young males, so as to provide simple methods for assessing vascular endothelial function in young students.

Methods A total of 137 young males were selected. Based on the BMI, the participants were divided into three groups: normal group (BMI 18.5 to ＜24 kg/m², 53 cases), overweight group (24 to ＜28 kg/m², 44 cases) and obesity group (≥28 kg/m², 40 cases). After 10 min rest, the blood pressure of both arms was measured twice by two electronic blood pressure monitors, with the average taken as the baseline blood pressure. A cuff of a mercury sphygmomanometer was then placed on the right upper arm and inflated to 30 mmHg above the systolic blood pressure for 5 minutes to induce transient right-arm ischemia. Subsequently, blood pressure in both arms was measured simultaneously using an electronic device. The diastolic blood pressure differences (Δd-IAD) between the two arms were calculated at baseline and after ischemia. Correlation analysis and multiple regression analysis were used to evaluate the relationship between BMI and Δd-IAD.

Results Before ischemia, there were no significant differences in the baseline d-IAD among the three groups (H = 4.918, P = 0.086). After ischemia, ∆d-IAD decreased significantly from normal weight to overweight, whereas the change from overweight to obesity was relatively modest. The ∆d-IAD values were 7.33 (3.08, 11.42) mmHg in the normal-weight group, 3.00 (0.42, 6.79) mmHg in the overweight group, and 1.50 (–0.96, 2.83) mmHg in the obesity group. Comparison between the normal-weight and overweight groups yielded U = 637.00, P＜0.001, and between the overweight and obesity groups, U = 633.00, P = 0.027. Multivariable analysis showed that BMI was an independent negative determinant of ∆d-IAD (β = –0.362, P＜0.001).

Conclusion In young males, BMI is independently and negatively correlated with Δd-IAD after short-term ischemia in the right arm.