Current Overview of Obesity-Induced Lymphedema.

Significance: Obesity affects one-third of the U.S. population and lymphedema is a chronic disorder without a cure. The relationship between obesity and lymphedema has important implications for public health. Recent Advances: Extreme obesity can cause lower extremity lymphedema, termed "obesity-induced lymphedema (OIL)." OIL is a form of secondary lymphedema that may occur once an individual's body mass index (BMI) exceeds 40. The risk of lymphatic dysfunction increases with elevated BMI and is almost universal once BMI exceeds 60. Patients with OIL also may develop areas of massive localized lymphedema (MLL). Critical Issues: Individuals with OIL are in an unfavorable cycle of weight gain and lymphatic injury. As BMI increases lymphedema worsens, ambulation becomes more difficult, and BMI further rises. The fundamental treatment for OIL is weight loss. Resection of areas of MLL and lower extremity volume reduction are performed when the BMI is lowered to <40 to reduce complications and recurrence. Future Directions: The mechanisms by which obesity causes lymphedema are still being elucidated. Although lymphatic function can improve following weight loss, it is unclear whether lymphedema may be completely reversed.