Definition1 & Origin
The word “lipedema” comes from the Greek word “lip/o” (meaning fat) & “edema” (meaning swelling). Lipedema is an abnormal proliferation of fat cells & swelling. It may also be called lipoedema. A chronic & progressive condition, this disorder is typically associated with hormonal changes or genetic predisposition & often co-exists with venous disorders & other vascular diseases.
Characteristics
It is found primarily in women & manifests as a symmetrical shape with an increase in fat tissue (similar to the shape of riding breeches) beginning near the waist (the iliac crest region) & extending to the ankles. There are two types: column-shaped & lobular.
Symptoms typically include swelling in the evening or in standing (i.e. orthostatic edema), increased sensitivity to pain, easy bruising, difficulty walking (due to the increased fat tissue), reduced elasticity & increased expandability of the skin & pituitary-thyroid or pituitary-ovarian hormone disturbances.
Pathology2
The proliferation of fat tissue compresses lymph collectors of the superficial lymph system. In lymphangiographic images (i.e. X-ray images), lymph collectors within the fat tissue have a coiled appearance (as opposed to being fairly straight in their path toward the lymph nodes where fluid continues to drain as in normal tissue). This coiled appearance reduces the flow of lymph fluid which causes fluid to “back up” in the affected area. In imaging, malformations are seen in the precursory vessels (lymph capillaries may have bulging areas & initial lymph channels are widened). Lipedema usually has loose connective tissue, so because there is not a lot of skin support, the pressure in the tissues is low which allows fluid to accumulate.3
According to Foldi, the initial cause of lipedema progression is microangiopathy within the area of fat tissue (i.e. a disease of the smallest blood vessels, the capillaries). As a result, blood capillary walls become thick & weak. Consequently, the capillaries become more permeable. They bleed, leak protein & slow the flow of blood. More fluid & proteins enter the tissue space (resulting in edema – as a result of increased hydrostatic pressure – &, ultimately, a greater demand on the lymphatic system). This leads to hypersensitivity of the tissue (people are usually very sensitive to touch). The blood capillaries are also more fragile which leads to bruising with mild trauma.
As lipedema progresses, the constant overload causes lymphatic vessels to develop additional structural changes. Mast cells in the tissue activate fibroblasts which results in interstitial fibrosis & development of lymphedema progression.
Diagnosis
As stated in the 2014 blog, lipedema is often misdiagnosed as obesity. Sometimes it is diagnosed as lymphedema as well. Imaging can be used (indirect lymphography would likely show prelymphatic channels to be large pools among other changes) but it is not necessary.7
Psych-social Effects
Lipedema is underdiagnosed4 & usually misdiagnosed as obesity. Patients are generally told they are fat & need to lose weight. Unfortunately, because lipedema cannot be “dieted away,” efforts to lose weight are unsuccessful. Some people may develop obesity as well due to frustration of unsuccessful dieting attempts & eventually develop a more sedentary lifestyle.3 It is interesting to note, some studies suggest not only does obesity contribute to the development of lymphedema but lymphedema can contribute to the development of fat tissue. 5, 6
Note: Dyslipidemia is not the same thing as lipedema. Dyslipidemia is an abnormal amount of lipids (like cholesterol &/or fat) in the blood & is frequently a result of diet & lifestyle.
References
1 Medical Terminology
2 Foldi, M, Foldi, E. (2006). Foldi’s Textbook of Lymphology (2nd ed.), p. 374-376. Germany: Urban & Fisher.
3 Lymphedema Management Comprehesive Guide (location 8661)
4 www.lipomacdoc.org/lipedema.html
5 Zampell JC, Aschen S, Weitman ES, et al. Regulation of adipogensis by lymphatic fluid stasis: Part I. Adipogeneis, fibrosis, and inflammation. Plast Reconstr Surg. 2012;129:825-834. (Vodder Review article)
6 Aschen S, Zampell JC, Elhadad S, Weitman E, De Brot M, Mehrara BJ. Regulation of adipogenesis by lymphaic fluid stasis: Part II. Expression of adipose differentiation genes. Plast Reconstr Surg. 2012; 129:838-847.
7 Foldi, M, Foldi, E. (2006). Foldi’s Textbook of Lymphology (2nd ed.), p. 423. Germany: Urban & Fisher.
