Randomised placebo-controlled trial to evaluate the effect of vitamin A on mother-to-child transmission of HIV-1 in Bloemfontein

[摘要] English: Mother-to-child (vertical) transmission is the primary means by which young childrenacquire human immunodeficiency virus type 1 (HIV -1) infection. Anti-retrovirals such asZidovudine and nevirapine can reduce vertical transmission of HIV significantly, but thistreatment is still largely unaffordable in Africa. Maternal vitamin A deficiency issuspected to enhance vertical transmission of HIV. Furthermore, vitamin A is known toact as a coenzyme to the immune process. Therefore, a double-blind randomized placebocontrolled trial to assess the effect of vitamin A supplementation on vertical transmissionof HIV was launched in Bloemfontein in 1997.A total of 2949 pregnant women attending the antenatal clinics at Pelonomi andUniversitas hospitals and the Mangaung University Community Partnership clinic werecounselled for HIV testing, and 2543 were willing to be screened by HIV testing forpossible inclusion in the trial. Of the women screened 595 (23.4%) were HIV positive,and 303 of these were willing to participate in the trial. 152 women were randomized tovitamin A treatment and 151 to placebo treatment. Patients were seen at 2 monthlyintervals in the antenatal phase. Post-natally mother-infants pairs were seen when theinfant was 1 month old, 3 months old, and thereafter, 3 monthly till 18 months old. Atotal of 191 patients (63% of all the study participants) missed one or more visits and hadto be traced.Of the 303 patients included in the study 158 had a conclusive infant HIV test result(patients in the Intention To Treat (!TT) analysis population) and 104 patients had aconclusive infant mv test result when the baby was 3 months old (patients in the PerProtocol (PP) analysis population). Of 158 patients, in the ITT population 73 were in thevitamin A group and 85 in the placebo group. Per treatment group the baselinecharacteristics of those in the IIT population and those who are not, did not differsignificanti y.The mv transmission rates were 19.2% and 21.2% for vitamin A and placebo groupsrespectively (IIT population). There is no statistically significant difference in thetransmission rates between vitamin A and placebo groups (p=0.76). Overall, this studyprovides no evidence that vitamin A is effective in reducing vertical mv-1 transmissionrate.There was no statistically significant difference in the percentages of mv symptomsrecorded at post delivery visit 1 through to the 18 months visit between the two treatmentgroups for either mothers or infants. A similar pattern was observed for the vital signs forthe mothers. The full blood and T-cell counts were similar between the two treatmentgroups at all visits for both mothers and infants.Only 4 patients reported adverse events; these were not related to the treatment. Twenty sixinfants and one mother died during the study. The overall infant mortality rate was85.8 per 1000 infant population. The infant death rates were approximately 11% in theplacebo group and 6% in the vitamin A group (p=0.097). Thus, Vitamin A was associatedwith a reduction in infant mortality, although not statistically significant. This associationmay be worth further investigation as there is potential for a substantial impact.

[发布机构] University of the Free State