Lipedema and Dercum's Disease: A New Application of Bioimpedance

Abstract

Background: Lipedema and Dercum's disease (DD) are incompletely characterized adipose tissue diseases, and objective measures of disease profiles are needed to aid in differential diagnosis. We hypothesized that fluid properties, quantified as tissue water bioimpedance in the upper and lower extremities, differ regionally between these conditions. Methods and Results: Women (cumulative n = 156) with lipedema (n = 110), DD (n = 25), or without an adipose disease matched for age and body mass index to early stage lipedema patients (i.e., controls n = 21) were enrolled. Bioimpedance spectroscopy (BIS) was applied to measure impedance values in the arms and legs, indicative of extracellular water levels. Impedance values were recorded for each limb, as well as the leg-to-arm impedance ratio. Regression models were applied to evaluate hypothesized relationships between impedance and clinical indicators of disease (significance criteria: two-sided p < 0.05). Higher extracellular water was indicated (i) in the legs of patients with higher compared with lower stages of lipedema (p = 0.03), (ii) in the leg-to-arm impedance ratio in patients with lipedema compared with patients with DD (p ≤ 0.001), and (iii) in the leg-to-arm impedance ratio in patients with stage 1 lipedema compared with controls (p ≤ 0.01). Conclusion: BIS is a noninvasive portable modality to assess tissue water, and this device is available in both specialized and nonspecialized centers. These findings support that regional bioimpedance measures may help to distinguish lipedema from DD, as well as to identify early stages of lipedema.

Keywords: Dercum's disease; adiposis dolorosa; bioimpedance spectroscopy; lipedema; lipoedema.

FIG. 1.

Example photos of patients with lipedema stages 1, 2, or 3 and a patient with DD reveal body shape characteristics of these adipose tissue diseases. Note the disproportionate size of the lower extremities in patients with lipedema, and the swollen appearance of the abdomen in DD. DD, Dercum's disease. Color images are available online.

FIG. 2.

Volunteers received a physical examination and bedside BIS measurement. (A) Participants were evaluated for lipedema and DD, and staging of lipedema. The texture of the skin and presence of lipomas were palpated. (B) BIS is demonstrated with application of electrodes on the hands and wrist. Additional electrodes on the feet and ankles were applied to measure impedance in the arms and legs bilaterally. BIS, bioimpedance spectroscopy. Color images are available online.

FIG. 3.

Bioimpedance (A, B) R₀ and (C, D) R_∞ values were found to decrease in the arms and legs of patients with higher compared with lower stages of lipedema. Decreasing trends for R₀ and R_∞ indicate increased extracellular water content and total limb water content, respectively. A significant relationship between R₀ and lipedema stage in the legs indicates greater extracellular water in the legs of patients with higher stages of lipedema (p = 0.03). *BIS metric demonstrates a significant relationship with disease status (p < 0.05) in a multivariable regression model also accounting for age and BMI as covariates. Model statistics are reported in Supplementary Table S1. BMI, body mass index. Color images are available online.

FIG. 4.

Bioimpedance (A) R₀ and (B) R_∞ ratios in the leg/arm were lower in patients with lipedema than in patients with DD. Lower impedance ratios indicate greater extracellular water (R₀) and total limb water (R_∞) in legs of patients with lipedema compared with those in patients with DD, and also underscore the potential systemic involvement of DD. *BIS metric demonstrates a significant relationship with disease status (p < 0.05) in a multivariable regression model also accounting for age and BMI as covariates. Model statistics are reported in Supplementary Table S2. Color images are available online.

FIG. 5.

Bioimpedance (A) R₀ and (B) R_∞ ratios in the leg/arm were lower in patients with lipedema stage 1 than in healthy female controls. This finding indicates disproportionate water distribution in patients with lipedema compared with controls matched for age and BMI. *BIS metric demonstrates a significant relationship with disease status (p < 0.05) in a multivariable regression model also accounting for age and BMI as covariates. Model statistics are reported in Supplementary Table S3. Color images are available online.