The effect of at-birth vitamin A supplementation on differential leucocyte counts and in vitro cytokine production: an immunological study nested within a randomised trial in Guinea-Bissau.

Vitamin A supplementation (VAS) at birth was not associated with improved survival in a randomised, placebo-controlled trial in Guinea-Bissau. However, a negative sex-differential effect, which became evident after diphtheria-tetanus-pertussis (DTP) vaccination, was noted; among girls who had received DTP, VAS at birth was associated with two-fold higher mortality than placebo. The objective of the present study was to investigate the immunological effects of VAS at birth within a subgroup of participants in the randomised trial. Guided by the mortality results, we further explored whether VAS had a differential effect according to sex and DTP status. At 6 weeks after randomisation and supplementation, we measured differential leucocyte counts and TNF-α, interferon-γ, IL-10, IL-13 and IL-5 production in a whole-blood culture assay. A total of 471 children were included. VAS compared with placebo at birth was associated with a higher proportion of monocytes (relative risk ratio 1·26, 95 % CI 1·07, 1·49, P=0·04), while spontaneous TNF-α production was lower in the VAS group (geometric mean ratio 0·54, 95 % CI, 0·37, 0·78, P=0·001). Stratified analysis showed that VAS was associated with lower TNF-α and IL-10 production for girls without DTP and boys with DTP, resulting in significant three-way interactions between VAS, sex and DTP vaccination status (P=0·03 and P=0·04, respectively) for spontaneous TNF-α and IL-10 production. The results substantiate the potential role of VAS as an immunomodulatory intervention, which has different effects depending on concomitant health interventions and the sex of the recipient.

Non-specific effects of standard measles vaccine at 4.5 and 9 months of age on childhood mortality: randomised controlled trial.

OBJECTIVE: To examine in a randomised trial whether a 25% difference in mortality exists between 4.5 months and 3 years of age for children given two standard doses of Edmonston-Zagreb measles vaccines at 4.5 and 9 months of age compared with those given one dose of measles vaccine at 9 months of age (current policy). DESIGN: Randomised controlled trial. SETTING: The Bandim Health Project, Guinea-Bissau, which maintains a health and demographic surveillance system in an urban area. PARTICIPANTS: 6648 children aged 4.5 months of age who had received three doses of diphtheria-tetanus-pertussis vaccine at least four weeks before enrolment. A large proportion of the children (80%) had previously taken part in randomised trials of neonatal vitamin A supplementation. INTERVENTION: Children were randomised to receive Edmonston-Zagreb measles vaccine at 4.5 and 9 months of age (group A), no vaccine at 4.5 months and Edmonston-Zagreb measles vaccine at 9 months of age (group B), or no vaccine at 4.5 months and Schwarz measles vaccine at 9 months of age (group C). Main outcome measure Mortality rate ratio between 4.5 and 36 months of age for group A compared with groups B and C. Secondary outcomes tested the hypothesis that the beneficial effect was stronger in the 4.5 to 9 months age group, in girls, and in the dry season, but the study was not powered to test whether effects differed significantly between subgroups. RESULTS: In the intention to treat analysis of mortality between 4.5 and 36 months of age the mortality rate ratio of children who received two doses of Edmonston-Zagreb vaccine at 4.5 and 9 months of age compared with those who received a single dose of Edmonston-Zagreb vaccine or Schwarz vaccine at 9 months of age was 0.78 (95% confidence interval 0.59 to 1.05). In the analyses of secondary outcomes, the intention to treat mortality rate ratio was 0.67 (0.38 to 1.19) between 4.5 and 9 months and 0.83 (0.83 to 1.16) between 9 and 36 months of age. The effect on mortality between 4.5 and 36 months of age was significant for girls (intention to treat mortality rate ratio 0.64 (0.42 to 0.98)), although this was not significantly different from the effect in boys (0.95 (0.64 to 1.42)) (interaction test, P=0.18). The effect did not differ between the dry season and the rainy season. As neonatal vitamin A supplementation is not WHO policy, the analyses were done separately for the 3402 children who did not receive neonatal vitamin A. In these children, the two dose Edmonston-Zagreb measles vaccine schedule was associated with a significantly lower mortality between 4.5 and 36 months of age (intention to treat mortality rate ratio 0.59 (0.39 to 0.89)). The effect was again significant for girls but not statistically significant from the effect in boys. When measles cases were censored, the intention to treat mortality rate ratio was 0.65 (0.43 to 0.99). CONCLUSIONS: Although the overall effect did not reach statistical significance, the results may indicate that a two dose schedule with Edmonston-Zagreb measles vaccine given at 4.5 and 9 months of age has beneficial non-specific effects on children's survival, particularly for girls and for children who have not received neonatal vitamin A. This should be tested in future studies in different locations. TRIAL REGISTRATION: Clinical trials NCT00168558.

Vitamin D as supplementary treatment for tuberculosis: a double-blind, randomized, placebo-controlled trial.

RATIONALE: Vitamin D has been shown to be involved in the host immune response toward Mycobacterium tuberculosis. OBJECTIVES: To test whether vitamin D supplementation of patients with tuberculosis (TB) improved clinical outcome and reduced mortality. METHODS: We conducted a randomized, double-blind, placebo-controlled trial in TB clinics at a demographic surveillance site in Guinea-Bissau. We included 365 adult patients with TB starting antituberculosis treatment; 281 completed the 12-month follow-up. The intervention was 100,000 IU of cholecalciferol or placebo at inclusion and again 5 and 8 months after the start of treatment. MEASUREMENTS AND MAIN RESULTS: The primary outcome was reduction in a clinical severity score (TBscore) for all patients with pulmonary TB. The secondary outcome was 12-month mortality. No serious adverse effects were reported; mild hypercalcemia was rare and present in both arms. Reduction in TBscore and sputum smear conversion rates did not differ among patients treated with vitamin D or placebo. Overall mortality was 15% (54 of 365) at 1 year of follow-up and similar in both arms (30 of 187 for vitamin D treated and 24 of 178 for placebo; relative risk, 1.19 [0.58-1.95]). HIV infection was seen in 36% (131 of 359): 21% (76 of 359) HIV-1, 10% (36 of 359) HIV-2, and 5% (19 of 357) HIV-1+2. CONCLUSIONS: Vitamin D does not improve clinical outcome among patients with TB and the trial showed no overall effect on mortality in patients with TB; it is possible that the dose used was insufficient. Clinical trial registered with www.controlled-trials.com/isrctn (ISRCTN35212132).

Effect of vitamin A supplementation with BCG vaccine at birth on vitamin A status at 6 wk and 4 mo of age.

BACKGROUND: The effect of vitamin A supplementation (VAS) at birth on subsequent vitamin A status has not been studied. OBJECTIVE: The objective was to study the effect of 50,000 IU vitamin A administered with BCG vaccine at birth on vitamin A status in both sexes. DESIGN: Within a randomized placebo-controlled trial of VAS, we obtained blood from 614 children at 6 wk of age and from 369 mother-infant pairs at 4 mo of age. We assessed vitamin A status on the basis of serum retinol-binding protein (RBP) and measured serum C-reactive protein to monitor for concurrent infections. RESULTS: RBP concentrations indicated vitamin A deficiency in 32% of the children at age 6 wk and in 16% at age 4 mo. VAS was not associated with higher RBP concentrations overall or in either sex. However, the effect of VAS varied with maternal education (P for interaction = 0.004): At age 6 wk, VAS was associated with higher (9%; 95% CI: 2, 17%) RBP concentrations in children of noneducated mothers but not in children of educated mothers. Overall, RBP concentrations increased between 6 wk and 4 mo of age. The increase correlated inversely with the number of diphtheria-tetanus-pertussis (DTP) vaccines received in the interval (P = 0.009), particularly in girls (P for interaction = 0.01) and in vitamin A recipients (P = 0.01). CONCLUSIONS: Overall, VAS at birth had no effect on vitamin A status. However VAS may temporarily improve vitamin A status in the subgroup of children of noneducated mothers. In vitamin A recipients, subsequent DTP vaccines affected vitamin A status negatively. The main trial was registered at clinicaltrials.gov as NCT00168597.

Effect of high-dose vitamin A supplementation on the immune response to Bacille Calmette-Guerin vaccine.

BACKGROUND: Vitamin A supplementation (VAS) at birth has been associated with decreased mortality in Asia. Bacille Calmette-Guérin (BCG) vaccine is given at birth in tuberculosis-endemic countries. Previous studies suggest that VAS may influence the immune response to vaccines. OBJECTIVE: Our objective was to examine whether VAS influences the immune response to simultaneously administered BCG vaccine. DESIGN: Within a randomized trial of 50,000 IU vitamin A or placebo given with BCG vaccine at birth in Guinea-Bissau, 2710 infants were examined for BCG scar formation and delayed-type hypersensitivity (DTH) to purified protein derivative of Mycobacterium tuberculosis (PPD) at 2 and 6 mo of age. The ex vivo cytokine response to PPD was measured in 607 infants. RESULTS: At 2 mo of age, 39% (43% of the boys and 34% of the girls) responded to PPD. The prevalence ratio of a measurable PPD reaction for VAS compared with placebo recipients was 0.90 (95% CI: 0.80, 1.02) for all infants, 0.81 (95% CI: 0.69, 0.95) for boys, and 1.04 (95% CI: 0.86, 1.26) for girls. At 6 mo of age, 42% of the infants responded to PPD. No difference was observed between VAS and placebo recipients. The prevalence of BCG scar was not affected by VAS. The ex vivo interferon-gamma response to PPD was increased by VAS (means ratio: 1.40; 95% CI: 1.03, 1.91). CONCLUSIONS: VAS with BCG vaccination does not appear to interfere with the long-term immune response to BCG. However, VAS temporarily altered the DTH reaction to PPD in boys at 2 mo of age, suggesting sex differences in the immunologic response to VAS given with BCG. This trial was registered at www.clinicaltrials.gov as #NCT00168597.