Caution for High-Dose Multivitamin Use in HIV

CHICAGOAfter research had found high-dose multivitamin use in HIV patients not receiving  highly active antiretroviral therapy (HAART) increased immune function and limited HIV disease progression, follow-up study has shown high-dose multivitamin use in combination with HAART can contribute to potentially negative changes in liver function in HIV patients. Results of the trial were published in the Oct. 17 issue of JAMA (308(15):1535-1544).

The Harvard-run study involved seven clinics in Tanzania, Africa, and compared high-does to regular-dose multivitamins in HIV patients on HAART therapy. The randomized, double-blind, controlled trial included 3,418 patients and ran for 24 months between November 2006 and November 2008. The multivitamin was in the form of an oral supplement containing vitamin B complex, vitamin C, and vitamin E.

Researchers halted the study in March 2009 after finding patients in the high-dose group had increased levels of alanine transaminase (ALT), a liver enzymeelevated levels of ALT can indicate liver injury or malfunction. After processing the data from the abbreviated trial, researchers also noted there was no difference between the high- and regular-dose groups in terms of disease progression.

"Further investigation is required to understand how micronutrient supplements can be best positioned alongside antiretroviral drugs to reduce morbidity and mortality due to HIV," the authors wrote, acknowledging the mechanism behind the increased ALT side effect in this trial in not known. "As different doses may have different effects, dose-finding trials with a placebo control are warranted to confirm the potential benefits of multivitamin supplementation on clinical outcomes, and to identify the lowest safe and effective dose in the context of HAART."

As the main processing organ for toxins, drugs and other compounds, the liver can be overtaxedsometimes the combination of medicines and supplements can overwork the liver and result in elevated liver enzyme levels. The researchers found elevated ALT in the high-dose group, not the standard group.

Duffy MacKay, N.D., vice president of science and regulatory affairs for the Council for Responsible Nutrition (CRN), said the study opens up the question of what the optimal dose of multivitamins is in this population and treatment combination, taking into account the effect of nutrients from the diet. He explained the standard-dose multivitamin may fill in nutritional gaps HIV patients commonly suffer. "Physicians should monitor liver enzymes whenever new therapeutic agents are added to treatment regimens," he cautioned, noting there is always the possibility new treatments, even if normally beneficial and safe, could tax the liver, especially in cases such as HIV that feature multiple treatments.

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