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.
The presence of edema means that there is more fluid than normal in the space between the cells. Usually, this extra fluid comes from the fluid inside the blood vessels. Edema of any cause is often worst in the legs and ankles. When weâre sitting or standing, gravity pulls the water inside blood vessels downward.