Background: Obesity is a risk factor for the development of secondary lymphedema after axillary lymphadenectomy and radiation therapy. The purpose of this study was to determine whether obesity influences the morbidity of lymphedema in patients who have the condition.
Methods: Two cohorts of patients were compared: group 1, normal weight (body mass index ≤25 kg/m); and group 2, obese (body mass index ≥30 kg/m). Inclusion criteria were patients aged 21 years or older with lymphedema confirmed by lymphoscintigraphy. Covariates included age, sex, lymphedema type (primary or secondary), location, comorbidities, lymph node dissection, radiation therapy, lymphoscintigram result, and disease duration. Outcome variables were infection, hospitalization, and degree of limb overgrowth. The cohorts were compared using the Mann-Whitney U test, Fisher's exact test, and multivariable logistic regression.
Results: Sixty-seven patients were included: group 1, n = 33; and group 2, n = 34. Disease duration did not differ between groups (p = 0.72). Group 2 was more likely to have an infection (59 percent), hospitalization (47 percent), and moderate or severe overgrowth (79 percent), compared to group 1 (18, 6, and 40 percent, respectively; p < 0.001). Multivariable logistic regression showed that obesity was an independent risk factor for infection (OR, 7.9; 95 percent CI, 2.5 to 26.3; p < 0.001), hospitalization (OR, 30.0; 95 percent CI, 3.6 to 150.8; p < 0.001), and moderate to severe limb overgrowth (OR, 6.7; 95 percent CI, 2.1 to 23.0; p = 0.003).
Conclusions: Obesity negatively affects patients with established lymphedema. Obese individuals are more likely to have infections, hospitalizations, and larger extremities compared to subjects with a normal body mass index. Patients with lymphedema should be counseled about the negative effects of obesity on their condition.
Clinical question/level of evidence: Risk, II.