To review the relationship between cognitive function and cataract surgery, as it is rarely addressed, and yet is becoming increasingly important as the number of elderly people in the world continues to rise.
From US Census and international data, it is expected that the predicted proportion of people over 65 years of age in a number of countries will increase drastically over a half century. Therefore, the percentage of patients with cataracts and cognitive impairment, which are both age-related diseases, will be expected to rise as well. Although there are many papers reporting on the association between visual impairments and cognitive impairments, there is a relative dearth of research supporting the hypothesis that cataract surgery can improve cognitive function in patients with cognitive impairment. This reflects some inherent problems with most cognitive tests, which include both vision-dependent and vision-independent items. There may also be an element of learning from repeated cognitive tests, which may falsely elevate test scores.
There is an increase in reports supporting the hypothesis that cataract surgery can improve cognition; however, there is still insufficient evidence for cognitive improvement after cataract surgery. As this is a growing area of research, we expect more studies to shed light on this relationship.
Shiley Eye Institute, University of California, San Diego, La Jolla, California, USA
Correspondence to Hideki Fukuoka, Shiley Eye Institute, University of California, San Diego, 9415 Campus Point Dr, La Jolla, CA 92093, USA. Tel: +1 858 822 1569; fax: +1 858 822 1514; e-mail: email@example.com