Prevalence, presentation and factors associated with low serum vitamin b-12 levels in ART-naïve HIV positive patients attending two outpatient HIV Care Clinics in Mulago Hospital

Abstract

Introduction: The extent of vitamin B-12 depletion among HIV positive patients in Uganda and Sub Saharan Africa is unknown. We describe serum vitamin B-12 levels and factors associated with suboptimal vitamin B-12 among HIV positive ART-naïve adults at two ambulatory HIV care centres in Kampala, Uganda. Methods: A cross-sectional study of ART-naive HIV positive patients at Mulago-Mbarara teaching hospitals’ Joint AIDS Program (MJAP) and the Infectious Diseases Institute (IDI) clinics, in Kampala was done. Demographic characteristics and clinical parameters were evaluated and blood samples were tested for serum vitamin B-12, CD4+ T cell counts, complete blood count and thin films. Results: The mean age of all the 204 patients was 34.4 (S.D. 9.4) years. The mean vitamin B-12 level was 384 pg/ml, normal range (200-900). Suboptimal vitamin B-12 levels (<300pg/ml) were found in 75/204 (36.8%). Up to 21/204 (10.3%) had vitamin B-12 deficiency (<200pg/ml) and 54/204 (26.5%) had marginal depletion (200-300 pg/ml). Median CD4+ T cells count was 418 (IQR 323-576) cells/µl and mean haemoglobin was 12.8 (S.D. 2.2) g/dl. Of the 75 patients with suboptimal vitamin B-12, 57 were female (76 %). Patients with suboptimal vitamin B-12 levels were more likely to be from northern Uganda (9.3% vs. 4.7%; P<0.001), have irritable mood (25.3% vs. 13.3%; P=0.034) and WHO Stage I (52% vs. 33.6%; P=0.01) relative to the patients with normal vitamin B-12 levels. Compared to those with normal vitamin B-12 levels, patients with vitamin B-12 deficiency had a longer mean duration from HIV diagnosis, at 42.2 months (S.D 27.1) vs. 29.4 (S.D 23.8; P=0.021). Reported use of a vitamin supplement in the previous year was 39.9% (59/148). Conclusions: The prevalence of suboptimal vitamin B-12 in this HIV positive ambulatory patient population in urban Uganda is as high as that described in developed countries. We recommend studies to assess the associated factors and explore the role of vitamin B-12 supplementation in this population.