If you're in the middle of the middle, however â not lower or upper-middle class â that would be an income range between $39,764 and $64,582, says Aaron Pacitti, an assistant professor of economics at Siena College in Loudonville, N.Y. Again, it isn't official.
Edema definition and facts. Edema is a swelling, usually of the legs, feet, and/or hands due to the accumulation of excessive fluid in the tissues. The edema that occurs in diseases of the heart, liver, and kidneys is mainly caused by salt retention, which holds the excess fluid in the body.
When blood pools in these veins, there is an increased chance that fluids will leak out into the surrounding tissues. Therefore, venous insufficiency can cause swelling in the ankles and feet. Edema due to chronic venous insufficiency can be recognized by the ulcers and color changes in the skin of the lower leg.