Progressive disease or progressive illness is a disease or physical ailment whose course in most cases is the worsening, growth, or spread of the disease. This may happen until death, serious debility, or organ failure occurs. Some progressive diseases can be halted and reversed by treatment. Many can be slowed by medical therapy. Some cannot be altered by current treatments.
Though the time distinctions are imprecise, diseases can be rapidly progressive (typically days to weeks) or slowly progressive (months to years). Virtually all slowly progressive diseases are also chronic diseases in terms of time course; many of these are also referred to as degenerative diseases. Not all chronic diseases are progressive: a chronic, non-progressive disease may be referred to as a static condition.
Progressive disease can also be a clinical endpoint i.e. an endpoint in a clinical trial.
Examples
There are examples of slowly and rapidly progressive diseases affecting all organ systems and parts of the body. The following are some examples of rapidly and slowly progressive diseases affecting various organ systems: