Older adults with cataracts are more likely to have symptoms of depression, reports a study published in December by the American Academy of Optometry.

The link between cataracts and depression appears strongest among older adults with lower education, according to new research by Haifang Wang of Soochow University, China, and colleagues.

"Our study sheds further light on the complex relationship between aging, vision loss, cataract, and depression, and suggests that there may be a role for cataract surgery in improving mental health in the elderly," the researchers write.

Age-related cataracts are the leading cause of visual impairment worldwide and expected to increase as demographics shift towards advancing age. Depression is also common in older adults.

Nearly half of older adults in this large study in Chinese older adults had cataracts in at least one eye. Eight percent of subjects had depressive symptoms. Symptoms were more common in women than men (11 versus 5 percent), and more common in older age groups.

Older adults with cataracts were more likely to have depressive symptoms, independent of socioeconomic status, lifestyle factors, and visual acuity. Symptoms of depression were 33 percent more likely when cataracts were present. The odds of depressive symptoms were similar for subjects with cataracts in one eye versus both eyes.

The association between cataracts and depression was even stronger for subjects with no formal education — a 50 percent increase. After all other factors were taken into account, cataracts explained 14 percent of the variation in depression risk.

The researchers note that their study cannot show whether vision loss might cause older adults to become isolated and withdrawn, or that depression might make them less likely to seek treatment for cataracts.

"These results suggest that vision care professionals should consider the broader impact that vision loss may have on mental health and well-being," said Michael Twa, Editor-in-Chief of Optometry and Vision Science. "As a next step, it would be important to know if the associated depression in older adults is reversible following the restoration of vision after cataract surgery."