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.
The higher pressure causes swelling in the legs and feet. Congestive heart failure, a condition in which the heart can no longer pump efficiently, causes fluid buildup in the lungs and other parts of the body. Swelling is often most visible in the feet and ankles. Pregnancy can cause edema in the legs as the uterus puts pressure on the vena cava. Fluid retention during pregnancy also can be caused by a more serious condition called preeclampsia. Low protein levels in the blood caused by malnutrition, kidney and liver disease can cause edema.