Gastric Bypass May Boost Blindness Risk
A lack of absorbed vitamin A is the link, researchers say
THURSDAY, June 15, 2006 (HealthDay News) -- A boom in gastric bypass surgery could lead to an unwelcome trend: an increase in vitamin A deficiency among patients that raises their risk for vision loss.
So conclude U.S. researchers who studied the medical histories of patients who were nearly blind or had very poor eyesight but no family history of blindness.
The study, published in the current issue of the British Journal of Ophthalmology, focused on three patients over age 65 who had been diagnosed with vitamin A deficiency. Each of the patients had also undergone major intestinal surgery in the last 20 to 35 years.
Vitamin A is needed to maintain healthy tissues and functions of the eye. Blindness or poor eyesight is one of the first symptoms of vitamin A deficiency, which results from malnutrition and is the primary cause of blindness in children in less affluent countries.
But researchers at Baylor College of Medicine in Houston note that vitamin A is absorbed through the small intestine. So, with gastric bypass surgeries on the rise, vitamin A deficiency may also increase in developed countries -- even though it's been predominantly an issue for underdeveloped countries until now.
Patients in the study had either intestinal bypass or gallbladder surgery, or surgery to remove tissue damaged by inflammatory bowel disease. Each patient had also taken vitamin A supplements, but still maintained poor eyesight. Two of the patients received intramuscular injections of vitamin A, and saw improvements in their vision within just a few days.
The Ohio State University has more information on vitamin A in the diet.