Cataracts - Prognosis

Prognosis

Some cataracts stop progressing after a certain point. Cataracts are never reversible, however, even after eliminating factors, such as drugs or illnesses, which might have promoted their development. If extensive and progressive cataracts are left untreated they can cause blindness. In fact, cataracts are the leading cause of blindness among adults age 55 and older. About 20.5 million Americans have at least one cataract. By 2020, that number is expected to jump to 30.1 million.

Fortunately, cataracts nearly always can be successfully removed with surgery. However, surgery is unavailable in certain parts of the world, leaving millions at risk for vision loss. Even in the U.S., where surgery has greatly reduced the risk of blindness, tens of thousands still lose their sight and millions more have poor vision because of cataracts.

Effect on Survival

In a 2001 study, cataracts were associated with a significantly higher mortality rate in older women, although not older men. These higher rates did not seem to be caused by certain health risks (for example, diabetes) that are often associated with both cataracts and lower survival rates. A 2004 study published by scientists in Italy appears to confirm the association between shortened lifespan and cataracts, especially cataracts confined to the lens nucleus and those that had already required surgery. A few other studies have also linked cataracts and vision impairment with poorer survival, regardless of accompanying health problems. One study reported that even middle-aged people with cataracts, particularly those in ethnic minority groups, had lower survival rates than their peers, perhaps because of premature aging.

Effect on Survival by Location of the Cataract. Some studies have suggested poorer survival specifically in patients with nuclear or mixed cataracts but not in those with cataracts in the cortex or capsule. Not all studies have found these differences. In any case, nuclear cataracts are highly associated with smoking and diabetes, although some studies have found lower survival rates in patients with nuclear cataract regardless of these health risks.