Low plasma zinc level and response to zinc supplement in HIV‐infected patients who have immunological discordance after antiretroviral therapy

Abstract

Purpose of the studyImmunological discordance in HIV‐infected patients is associated with the higher risk of mortality and disease progression. Zinc is an essential micronutrient for immune function. We aimed to determine plasma zinc level and immunological response after zinc supplementation in HIV‐infected patients with immunological discordance after antiretroviral therapy (ART).MethodsA pilot study of 2 phases including a cross‐sectional study to determine plasma zinc level in patients with immunological discordance and a prospective, randomized, open‐label, placebo‐controlled trial was conducted in HIV‐infected patients with immunological discordance in a medical‐school hospital. Immunological discordance was defined as patients who received ART, had complete virological response (HIV RNA<40 copies/ml), and had immunological response with CD4 cell count<200 cell/mm3 and increased less than 30% from baseline after ART with undetectable HIV RNA for at least 6 months. Plasma zinc level was measured and stratified into low (<75 µg/dL) and normal plasma zinc level. Patients were randomly assigned to receive zinc or placebo supplementation for 6 months. CD4 cell count was monitored every 3 months.Summary of resultsOf 31 patients, median (IQR) plasma zinc level was 76 (66–88) µg/dL (IQR) and 12 (38.7%) patients had low plasma zinc level. Five of 12 patients with low plasma zinc level and 8 of 19 patients with normal plasma zinc level were randomized to receive zinc supplementation. Median (IQR) change of plasma zinc level after zinc supplementation in patients with low and normal plasma zinc level were 29 (−2–50) and−8 (−17–10) µg/dL, respectively. Significant increase of CD4 cell count after zinc supplementation was observed in patients with low plasma zinc level. Median (IQR) CD4 cell count at baseline and after zinc supplementation were 176 (161–200) and 250 (192–262) cells/mm3. The effect of zinc supplementation compared to placebo on the rising of CD4 cell count was not significantly different in both patients with low and normal plasma zinc level.ConclusionsLow plasma zinc level is observed over one‐third of patients with immunological discordance. Zinc supplementation increases plasma zinc level and CD4 cell count in patients with low zinc level but the effect was not significant different from placebo. Further large‐scale study to determine long‐term benefit of zinc supplementation in patients with immunological discordance is needed.