Female sex was associated with lower venous compliance at low transmural pressures and greater net capillary fluid filtration compared to men during lower body negative pressure (P<0.05).
Observational (n=28)
Are there sex-related differences in venous compliance and capillary filtration in the lower limb during lower body negative pressure?
Sex differences in lower limb venous compliance are confounded by capillary fluid filtration, which is greater in women and must be corrected for in physiological assessments.
p-value: p=<0.05
Recent studies in humans have suggested sex differences in venous compliance of the lower limb, with lower compliance in women. Capillary fluid filtration could, however, be a confounder in the evaluation of venous compliance. The venous capacitance and capillary filtration response in the calves of 12 women (23.2 +/- 0.5 years) and 16 men (22.9 +/- 0.5 years) were studied during 8 min lower body negative pressure (LBNP) of 11, 22, and 44 mmHg. Calf venous compliance is dependent on pressure and was determined using the first derivative of a quadratic regression equation that described the capacitance-pressure relationship compliance = beta1 + (2 x beta2 x transmural pressure). We found a lower venous compliance in women at low transmural pressures, and the venous capacitance in men was increased (P < 0.05). However, the difference in compliance between sexes was reduced and not seen at higher transmural pressures. Net capillary fluid filtration and capillary filtration coefficient (CFC) were greater in women than in men during LBNP (P < 0.05). Furthermore, calf volume increase (capacitance response + total capillary filtration) during LBNP was equivalent in both sexes. When total capillary filtration was not subtracted from the calf capacitance response in the calculation of venous compliance, the sex differences disappeared, emphasizing that venous compliance measurement should be corrected for the contribution of CFC.
Lindenberger et al. (2006) reported an observational. Female sex vs. Male sex was evaluated on Venous compliance and capillary filtration response (p=<0.05). Female sex was associated with lower venous compliance at low transmural pressures and greater net capillary fluid filtration compared to men during lower body negative pressure (P<0.05).