Association Between Leg Venous Reflux and Fluid Accumulation Assessed by Bioelectrical Impedance Analysis: A Generalized Estimating Equation Analysis.

PURPOSE: Leg edema is common in chronic venous disease, but its relationship with venous reflux remains unclear. This study investigated the association between the venous filling index (VFI) and the extracellular water-to-total body water ratio (ECW/TBW).

METHODS

We analyzed 140 patients with saphenous varicose veins (280 limbs). ECW/TBW was measured using bioelectrical impedance analysis and VFI using air plethysmography. Generalized estimating equations (GEE) were used to account for within-patient correlation. The primary outcome was ECW/TBW (%) analyzed using GEE linear regression, and the secondary outcome was edema (ECW/TBW ≥0.390) analyzed using GEE logistic regression.

RESULTS

The mean age was 64.0 years, and 58.6% of patients were female. Mean ECW/TBW was 0.392 and mean VFI was 2.94 mL/s. In multivariable GEE linear regression, VFI was independently associated with higher ECW/TBW (%) (β=0.045 percentage points per 1 mL/s increase; 95% CI, 0.018-0.072; P<0.001). In multivariable GEE logistic regression, VFI was independently associated with edema (OR, 1.47; 95% CI, 1.22-1.76; P<0.001).

CONCLUSION

Greater venous reflux was independently associated with fluid accumulation and edema. ECW/TBW may provide an objective measure of venous-related fluid accumulation.