All About Cataracts

In the past, some have thought that Alzheimer’s patients would have difficulty in coping with cataract surgery and the resulting vision changes. But cognitive ability, mood and sleep patterns improved in cataract surgery patients with mild Alzheimer’s disease in a recent study.

The 38 subjects all had mild dementia and an average age of 85. They had advanced cataract in at least one eye and underwent a cataract removal operation that included implantation of artificial intraocular lenses. All but one of the patients experienced dramatic vision improvement at both near and far distances.

The ability to notice, understand and respond appropriately to their environments improved in 25 percent of the patients; also, many experienced relief from depression. Most of the patients showed improvement in sleep patterns and nighttime behavioral issues.

Brigitte Girard, MD, the lead researcher of the study, presented the findings at the annual meeting of the American Academy of Ophthalmology in late October.

If you have had cataract surgery, should you worry about your intraocular lenses eventually dislocating?

To answer this question, researchers at the Mayo Clinic checked the records of all residents of Olmsted County, Minn., who had undergone cataract extraction from Jan. 1, 1980 through May 31, 2009. In the 14,471 cataract cases studied, 16 cases of late posterior chamber IOL dislocation were identified.

The researchers calculated that at five, 10, 15, 20, and 25 years after cataract surgery, the cumulative risk of IOL dislocation was low, at 0.1%, 0.1%, 0.2%, 0.7%, and 1.7%, respectively. And the risk did not change much over the three-decade study period.

They also found that pseudoexfoliation and zonular laxity at surgery were significantly correlated with late IOL dislocation. (Pseudoexfoliation involves fluffy material appearing on the lens capsule; it can weaken the zonules, which are fibers that hold in place the chamber containing the cataract and later the intraocular lens. This weakness is called zonular laxity.)

The study report was published online in the American Journal of Ophthalmology on June 17.

A British study finds that vegetarians and vegans have a lower risk for cataracts than meat eaters. Compared with the heaviest meat eaters in the study, vegetarians had a 30 to 40 percent lower cataract risk.

Eating a diet high in vegetables may lower the risk for cataracts.

The researchers followed 27,600 non-diabetics age 40 and older for a period as long as 15 years. At the end of the study, about three in 50 meat eaters had cataracts, versus about two in 50 vegans and vegetarians.

Moderate meat eaters had a slightly lower cataract risk than that of the heaviest meat eaters, who ate more than 3.5 ounces of meat each day. Fish eaters had a 15 percent lower cataract risk than that of the heaviest meat eaters.

The results do not prove that meat consumption promotes cataracts, according to the researchers. Rather, vegetables may have protective nutrients that lower cataract risk, as suggested by other studies. In addition, vegetarians may practice other healthy lifestyle behaviors that can contribute to a lower risk for cataracts.

The study was reported in The American Journal of Clinical Nutrition.

A new study finds that people with metabolic syndrome have a higher risk for cataracts. According to the study, metabolic syndrome is having at least three of the following: a high level of bad cholesterol;  a body mass index (BMI) of 25 or more; use of blood pressure medication or blood pressure of 130/85 or higher; and diabetes mellitus.

High blood pressure is associated with three cataract types, says study.

The researchers examined the association with three cataract types: nuclear, cortical and posterior subcapsular (PSC). They found that high blood pressure was linked to all three cataract types, and diabetes was associated with cortical and PSC cataracts.

Cortical cataracts were linked to high BMI, diabetes, high blood pressure and low high-density lipoprotein cholesterol. Study participants with both diabetes and high blood pressure had a four times greater cataract risk.

The study was reported in January on the website for Investigative Ophthalmology & Visual Science.