Calf And Forearm Venous Compliance In Older Adults

Abstract

Similar to changes in arterial compliance with aging, venous compliance in the lower extremities declines with age. There is evidence that venous compliance is lower in younger females than males but to date this potential sex difference has not been investigated in an older population. PURPOSE: To determine if there is a difference in the venous compliance of the extremities in older men and women. METHODS: Seventeen healthy adults over the age of 60 [10 male (65.4 ± 4.8 yrs, 31.5 ± 2.1 ml*kg-1*min-1), and seven female (69.1 ± 1.4 yrs, 22.4 ± 3.3 ml*kg-1*min-1) underwent submaximal graded exercise tests and assessments of calf and forearm venous compliance. Utilizing venous occlusion plethysmography, calf and forearm venous compliance was determined in both groups using the first derivative of the pressure-volume relation during cuff pressure reduction. Capacitance and capillary filtration volumes were determined from the increase in limb volume following cuff pressure inflation. Sex differences were assessed with a simple ANOVA. RESULTS: The males were significantly larger than the females (P < 0.05; BMI 28.7 ± 3.2 kg/m2 vs. 24.5 ± 2.1 kg/m2 and calf volume 44.2 ± 2.2 cm vs. 36.6 ± 3.6 cm) and were also significantly more fit than the females (P < 0.05; VO2peak estimated from submaximal test; 31.5 ± 2.1 ml*kg-1*min-1 vs. 22.4 ± 3.3 ml*kg-1*min-1). There were no differences in calf [males; DLimb Volume = 1.3229 ±.1229 +.0840 ±.0047 (Cuff Pressure) -.0007 ±.00006 (Cuff Pressure)2 vs. females; DLimb Volume = 1.4233 ±.3476 +.08658 ±.0049 (Cuff Pressure) -.0008 ±.00005 (Cuff Pressure)2] or forearm [males; DLimb Volume = 1.3811 ±.1388 +.0871 ±.0036 (Cuff Pressure) -.0006 ±.00017 (Cuff Pressure)2 vs. females; DLimb Volume = 1.4327 ±.3657 +.0850 ±.00365 (Cuff Pressure) -.0008 ±.00005 (Cuff Pressure)2] venous compliance, capacitance or capillary filtration volumes between the sexes in either limb. CONCLUSION: Sex differences that might exist in younger individuals do not exist in an older healthy population. Despite a significantly higher estimated VO2peak, the older males had similar venous characteristics in their extremities as the older females. These results suggest that males may lose venous compliance with age faster than females.