A pre-existing condition is a medical condition that an individual has prior to obtaining health insurance. Insurance companies define what conditions are classified as pre-existing.
Pre-existing conditions range from serious conditions such as cancer to milder afflictions such as asthma. Before the enactment of the Affordable Care Act, insurance companies routinely denied applicants or charge higher premiums due to pre-existing conditions. As a result of the Affordable Care Act, insurance companies may not deny applicants, charge them higher premiums, force them to undergo a waiting period before providing coverage or limit insurance benefits based on pre-existing conditions. Studies show that one in two Americans and 86 percent of elderly Americans have pre-existing conditions.