HIV carriers deficient in vitamin B12 appear to get AIDS faster, study says Hopkins research finds a link worth pursuing


WASHINGTON -- Men who are infected with the virus that causes AIDS appear to progress to the full-blown disease much more quickly if they are deficient in vitamin B12, researchers at the Johns Hopkins University said yesterday.

Scientists said a study of 310 gay and bisexual men who were infected with human immunodeficiency virus, which causes AIDS, found that those with adequate blood levels of B12 remained free of the disease for about eight years, compared with four years for those deficient in the nutrient.

The researchers, led by Dr. Alice M. Tang of the Johns Hopkins School of Hygiene and Public Health, said two other important nutrients tested, vitamin B6 and folic acid, had shown no similar link with the timing of the development of AIDS by men infected by HIV.

Tang said that even though her work and similar observational studies by other researchers did not prove that B12 deficiencies meant less favorable outcomes for HIV-infected patients, the link was strong enough to be examined more rigorously in controlled clinical trials.

"We need to do clinical trials to see if improvement in the levels of nutrients like B12, with vitamin supplements, delays disease progression or improves outcome," she said in a telephone interview. "Further studies are needed to determine the cause of low B12 levels."

But Tang said results of her study, published in the February issue of the Journal of Nutrition, suggest that HIV-infected patients should have their B12 levels monitored and take steps to maintain adequate nutrition.

The B vitamins, including B12 and folic acid, play crucial roles in protein and DNA synthesis, experts say, and deficiencies can lead to immune and cognitive problems. The chief sources of B12, a water-soluble vitamin that is not stored in the body, are animal products, including meat, milk and eggs.

In the new study, Dr. Tang and her colleagues noted that other researchers had found that serum levels of vitamins B6 and B12 tended to be low among people infected with HIV and had seen less consistent evidence of a link to some folic acid deficiencies.

It remains uncertain whether vitamin B12 concentrations are a contributing factor to HIV progression or the result of the infection, the researchers said, but evidence from their study points to the former.

The researchers studied men with an average age of 34 from the Baltimore-Washington area who had enrolled in an AIDS study in 1984. The scientists examined blood samples taken at the start of this study and examined the men periodically for nine years to look at changes in serum levels of micronutrients. They also used food questionnaires to assess food intake.

The researchers found that 12 percent of the men had low vitamin B12 levels, that 11 percent had low serum B6 and that 8 percent were deficient in folate, or folic acid.

"We found that the median AIDS-free time was four years shorter in the low serum-vitamin B12 group," they said. "However, for the other two micronutrients studied, neither low serum concentrations of vitamin B6 or low levels of folate were associated with quicker progression to AIDS."

To address the question of whether the vitamin B12 deficiency was the contributing factor, the researchers did an analysis with 217 test subjects who had shown no AIDS symptoms when they entered the study.

Looking at only the healthiest patients, Tang said, the researchers still found that low B12 levels were significantly associated with an increased risk of progression to AIDS.

Pub Date: 2/01/97

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