Duration of disability
Your impairment/injury must be severe enough to disable you (as per the SSA’s medical criteria) for at least 12 continuous months or result in your death. This does not mean that you have to be severely ill for a year, just that it can be expected to last for at least one year. This is on the SSA’s presumption that if an impairment/injury will last for a year, if, there is no improvement in three months.
There is an SSA’s official “Listing of Impairments” for all major body parts that describes medical conditions that are considered severe to automatically classify your impairment as disability. Many of them are anticipated to eventually result in death.