About the data: We used the family income data from the 2013 American Community Survey. This counts only families, which the government defines as households with two or more people related by birth, marriage or adoption. The graph focuses on families living in the country's 30 most populous cities.
Diseases and conditions that may cause edema include: 1  Congestive heart failure. 2  Cirrhosis. 3  Kidney disease.  Kidney 1  damage. Weakness or damage to veins in your legs.  Inadequate lymphatic 1  system. Symptoms.  Risk factors.
Any hormone imbalance in your body could also cause edema to accumulate in your legs. Since gravity will always carry the fluid to the lowest part of your body, it is usually first becomes evident in the lower legs or feet. Vein malfunction / vein dysfunction is also another common cause of leg swelling.