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.
Swelling in the ankles and legs is called peripheral edema; it is typically caused by right-sided heart failure. This may lead to nocturnal polyuria, or frequent urination at night. Your body converts the excess fluid into urine, resulting in you waking up repeatedly during the night to urinate.