The authors have declared that no competing interests exist.
Conceived and designed the experiments: GC HS. Analyzed the data: GMC MA MJ. Wrote the paper: GC MA MJ DI AE SB HS. Database searches: GC KS. Data abstraction: GC KS MA. Statistical analyses: MJ.
Approximately 28.5 million people living with HIV are eligible for treatment (CD4<500), but currently have no access to antiretroviral therapy. Reduced serum level of micronutrients is common in HIV disease. Micronutrient supplementation (MNS) may mitigate disease progression and mortality.
We synthesized evidence on the effect of micronutrient supplementation on mortality and rate of disease progression in HIV disease.
We searched MEDLINE, EMBASE, the Cochrane Central, AMED and CINAHL databases through December 2014, without language restriction, for studies of greater than 3 micronutrients versus any or no comparator. We built a hierarchical Bayesian random effects model to synthesize results. Inferences are based on the posterior distribution of the population effects; posterior distributions were approximated by Markov chain Monte Carlo in OpenBugs.
From 2166 initial references, we selected 49 studies for full review and identified eight reporting on disease progression and/or mortality. Bayesian synthesis of data from 2,249 adults in three studies estimated the relative risk of disease progression in subjects on MNS vs. control as 0.62 (95% credible interval, 0.37, 0.96). Median number needed to treat is 8.4 (4.8, 29.9) and the Bayes Factor 53.4. Based on data reporting on 4,095 adults reporting mortality in 7 randomized controlled studies, the RR was 0.84 (0.38, 1.85), NNT is 25 (4.3, ∞).
MNS significantly and substantially slows disease progression in HIV+ adults not on ARV, and possibly reduces mortality. Micronutrient supplements are effective in reducing progression with a posterior probability of 97.9%. Considering MNS low cost and lack of adverse effects, MNS should be standard of care for HIV+ adults not yet on ARV.
Antiretroviral therapy (ARV) has revolutionized care and outcomes for HIV infected individuals. However, it remains out of reach for many, due to cost and other barriers.[
Vitamins and certain minerals (micronutrients) are essential for metabolic and immunologic functions. Micronutrient (MN) deficiencies arise due in part to inflammatory and immunological effects of HIV infection in the gut, which impairs absorption. In addition concurrent infections, antibiotic and other drug treatment may contribute to deficiencies.[
A prior metaanalysis was unable to make conclusive findings with regard to an effect on disease progression rate or mortality.[
Our objective was to synthesize the evidence of the effects of multiple micronutrient supplementation (MNS) reporting on the effects of MNS on mortality and the rate of disease progression among HIV+ adults not on ARV.
Our protocol was registered with PROSPERO[
We included clinical trials of individuals of any age with documented HIV infection with or without concurrent or active opportunistic or other infection and not on antiretroviral therapy. Most overthecounter MNS contain more than three ingredients. We included studies that investigated more than 3 micronutrients, as in other studies,[
We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (The Cochrane Library), AMED and CINAHL.
Databases were queried with the same search terms, tailored to the particular database. Our search terms are described in the Prospero protocol. Searches were conducted from database inception through December 2014. Review articles were assessed for additional references.
Two reviewers independently screened citations and abstracts of all publications obtained by the search strategies. Disagreements were resolved by consensus.
For eligible trials, we obtained full articles and assessed their relevance based on the preplanned criteria for inclusion in the systematic review.
We extracted data on study design, intervention, site, number of participants, inclusion and exclusion criteria, duration, toxicity/adverse events, primary endpoint, secondary endpoint, findings, baseline differences, conclusions, efficacy and safety.
We evaluated methodological quality based on the Jadad score,[
We built a hierarchical Bayesian random effects model to synthesize results. Inferences are based on the posterior distribution of the population effects; posterior distributions were approximated by Markov chain Monte Carlo in OpenBugs.[
The hierarchical Bayesian model for the progression data synthesizes the reported hazard rates from the studies, and their associated standard errors. Because we did not have sufficient information to develop a model of the standard errors, we assume they represent the true variation of the estimated relative risk around its true value. That is, we assume
The likelihood for our Bayesian hierarchical model of the mortality data assumes a probit regression model, where the observed fatalities in each arm of each study are assumed to be binomial random variables. The rate of fatalities in the control arm of study
The number needed to treat (NNT) is defined as
We undertook an assessment of heterogeneity and calculated a Bayes Factor for the likelihood of a 0 value for betweenstudy heterogeneity.[
We searched for evidence of selective reporting and for conflicts of interests, including eliciting the funding source of included studies. We attempted to assess publication bias.[
We reviewed studies for adverse events and summarized those studies excluded from our formal metaanalysis. Frequentist analyses were conducted for sensitivity (
Two reviewers extracted data from 49 of the initial 2,166 studies identified (
Reference  Location  Duration  Participants  Intervention  Control  Design  Jadad  Conclusions 

Abrams, 8100273; 1993  San Francisco, CA  72 months  San Francisco Men’s Health Study n = 296 HIV+ 25–50 yo gay men not on ARV  Each participant asked to record brand, frequency and amount of each supplement taken  None  Prospective, observational study  NA  High nutrient intake at baseline in HIV+ men was assoc. w/higher CD4 count and a reduced risk of AIDS; hazard ratio (HR) = 0.7; 95% CI = 0.5, 1.0 
Baum, 24281460; 2013  Botswana  24 months  N = 875 HIV+ adults not on ARV, CD4>350  B120 mg; B220 mg; B625 mg; Niacin100 mg; B1250 μg; C500 mg; E30 mg; Folic acid0.8 mg; Se200 μg  Placebo  RCT, factorial design  5  Long term MVI was safe and significantly prolonged time to CD4 <250; HR = 0.46, 95%CI: 0.25, 0.85, p = 0.01; 
Fawzi, 15229304; 2004  Tanzania  71 months  n = 1,078 pregnant women; placebo267; MV only271; MV+A 268; A only272  Placebo  RCT, 2x2 factorial design; Placebo vs. Vit A alone vs. MVs w/o Vit A  5  Progression reduced to stage 4; higher CD4 and lower viral load in MVI arm; RR 0.50 (0.28–0.90) p<0.02 over mean 61.4 months; 

Jiamton, 14600517; 2003  Thailand  11 months  HIV+ adults with CD4 of 50–550; n = 481  A3000 μg; Betacarotene6 mg; D320 μg; E80 mg; K80 μg; C400 mg; B124 mg; B215 mg; B640 mg; B1230 μg; Folacin100 μg; Pantothenic acid40 mg; Fe10 mg; Mg200 mg; Mn8 mg; Zn30 mg; I300 μg; Cu3 mg; Se400 μg; Cr150 μg; Cystine66 mg  Placebo  RCT  5  
Kelly, 18842788; 2008  Zambia  40 months  HIV/HIV+ adults: n = 500 (total); n = 148 (HIV+)  A10,500 IU; C300 mg; E300 mg; Se150 μg; Zn200 mg  Placebo  RCT, cluster randomized; midpoint crossover  5  
Range, 
Tanzania  8 months  Adults w/ TB, mixed HIV status: n = 499 (total); n = 213 (HIV+)  Placebo  RCT, 2x2; MNS +placebo vs. MNS+Zn vs. Zn+plac. vs. placebo/placebo  5  
Semba, 
Malawi  24 months  Adults w/ TB, mixed HIV status: n = 1402 (total); n = 829 (HIV+)  A 8000 IU; C500 mg; D400 IU; E200 IU; B62 mg; B126 μg; B11.5 mg; B21.7 mg; Niacin20 mg; Folate0.4 mg; Zn10 mg; I175 μg; Se65 μg  Placebo  RCT  5  
Villamor, 
Tanzania  43 months  Adults with TB: n = 887 (total); n = 471 (HIV+)  Retinol5000 IU; B120 mg; B220 mg; B625 mg; B1250 μg; Niacin100 mg; Folic acid0.8 mg; C500 mg; E500 mg; Se100μg  Placebo  RCT  5 
The Jadad scale (a score ranging from 1 to 5) was used to assess bias within studies.[
Synthesis of data from 2,249 participants in 3 trials shows that MNS reduces the risk of disease progression.[
Bayesian random effects analysis (favors treatment on the left of 1.0); density plots on the figure on the left represent combined data; on the right accounts for individual study arms and the impact of adding selenium or vitamin A to MNS [
When we used a very flat, uninformative and highly conservative parameter modeling a large between study variability with OR differences between studies of around 3[
Further, a sensitivity analysis employing frequentist methodology yielded a similar 40% reduction in the rate of progression to clinical disease stages (RR = 0.60; 0.46, 0.78; p = 0.00008) for subjects on MNS (
We identified seven pertinent RCTs with data (see
Bayesian random effects analysis (favors treatment on the left of 1.0); density plots on the figure on the left represent combined data; on the right accounts for individual study arms and the impact of adding selenium, vitamin A or zinc to MNS.
We performed a studylevel sensitivity stratified analysis controlling for TB coinfection. In a frequentist analysis, we estimated a RR of 0.70 (0.53, 0.93; p = 0.02) for the studies not including patients with TB (
Our Bayesian analysis, which assumed a nonzero between study variability, found that the posterior probability that micronutrients reduce mortality rates in the nonTB population is 96%; the estimate of the risk ratio is 0.73 (0.47, 1.10; p = 0.04). The estimate for the studies including patients with TB at baseline is RR 0.93 (0.59, 1.32; p = 0.29). The Bayesian approach led to wider credible intervals, because of the assumption of a nonzero between study variability.
6 of 8 studies explicitly reported on adverse events. Of these, none reported any serious side effects from MNS, with minor events being reported in one study more frequently among placebo recipients.[
Our evidence synthesis demonstrates that micronutrient supplementation substantially and significantly reduces the risk of HIV disease progression by 38% in adults not on ARV therapy. For disease progression, the NNT is 9.7. The probability that MNS slow HIV disease progression is 98.2%. The slowed rate of progression offers individuals not yet on ARV a potentially lifeextending stopgap as the goal of ARV access for all remains elusive. Other clinical benefits may additionally accrue (discussed below), with little evidence of risk of harm or excessive cost.
For mortality, the NNT was 25 (credible interval, 4.3—∞), with a 91% probability that MN supplement reduces mortality. This is particularly evident among individuals with low CD4 counts, although clearly such individuals should be on ARV therapy. With the current dataset, we cannot definitively assert an effect of MNS on mortality.
In our stratified analysis controlling for opportunistic coinfection, we found a stronger effect in studies that did not include patients with TB at baseline, both in the frequentist and the Bayesian analysis. We hypothesize that micronutrients may moderately reduce mortality risk among adults without concurrent opportunistic infection. However, we caution that this was an
Our Bayesian analysis included a positive value for between study variability, estimated to be 0.02 (0.0006, 0.15), i.e., about 2% of the observed variation could be said to be between study variation.
Our analyses demonstrate a significant and marked clinical benefit for adults with HIV not yet on ARV. However, benefits of MNS for those not on ARV should not serve as a rationale for delaying[
The annual cost per patient of MNS reported ranged from about $12 to $40/patient/year. One of the least costly ($12/pt/year) yet most comprehensive MVM formulae was the one clinically evaluated by Jiamton’s group.[
Future studies might assess optimized formulae and dosages. In the Fawzi study, increasing the dosage of the vitamin A may have blunted the impact on progression rate.[
Others have noted numerous clinical benefits of MNS were reported, including improved birth outcomes and gastrointestinal function, reduction in hospital stay, improvement in hematology and quality of life.[
MNS formulae that include a comprehensive array of vitamins and minerals (such as potassium, calcium, magnesium and selenium) may be more biologically relevant in the context of gut damage, mitochondrial toxicity, increased resting energy expenditure and oxidative stress observed in HIV infection and with chronic ARV treatment.[
The strongest effect on mortality among those with CD4<200 used a formula with a range of micronutrients including vitamin D3, zinc, copper and selenium, which also happened to be one of the least expensive.[
Use of MN supplements in the context of ARV therapy should be further assessed. While one study using a comprehensive intervention with high dosages showed increased CD4 among North Americans on ARV [
Certainly, addressing food and clean water needs is paramount. Food insecurity increases HIV+ individuals’ vulnerability in developing and developed countries, even in the United States.[
Our findings are robust to the statistical approach chosen: both Bayesian and frequentist analyses give similar estimates. Typical for a metaanalysis, our findings are sensitive to assumptions regarding the variability between studies. The effects are significant in spite of our very conservative estimate of the between studyvariability in our Bayesian model.
Bayesian evidence synthesis produces a posterior distribution of the probability for each possible value of the summary statistic, in our case the NNT. This gives an intuitive representation of likely effect sizes. Bayesian credible intervals provide evidence in favor of the null hypothesis instead of just a rejection of the null hypothesis. To reflect this difference we present the Bayesian estimates with posterior density strips.[
The included studies were conducted in different settings (industrialized versus developing countries). On one hand, the populations studied in the included trials differ, not only in gender but also in racial, ethnic or genetic factors and, to some degree, nutritional status. On the other hand, the baseline BMI in the gay men in California was around 24 versus 23 kg/m^{2} among the Tanzanian women, suggesting similar nutritional status, as other data support.[
The MNS interventions varied in content and strength. Some included minerals such as iron, zinc and selenium while others did not. However, for the progression analysis, there were greater similarities in the intervention used, including in terms of dosage.
Our conclusions are somewhat weakened by the small number of included studies; metaanalysis of only few studies may exaggerate the effect estimate.[
We recommend micronutrient supplementation among HIV+ adults not on ARV therapy. Some 35 million people are living with HIV, millions of whom despite clinical eligibility, are yet to be treated. While food and clean water as well as access to ARV remain priorities, potentially costeffective micronutrient supplementation to slow disease progression and reduce mortality is compelling. Further studies of optimal micronutrient formulae among individuals receiving ARV are warranted.
A frequentist analysis yielded a similar 40% reduction in the rate of progression to clinical disease stages (RR 0.60, 95% CI 0.46, 0.78; p = 0.00008) for subjects on MNS, when including supplement arms that included a MNS alone or MNS plus either zinc or selenium.
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Frequentist analysis of mortality across studies yielded a RR of 0.87 (0.73, 1.04; p = 0.12).
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A study level sensitivity analysis excluding studies that included TB and HIV coinfected patients at baseline under frequentist analysis yielded a RR of mortality of 0.70 (0.53, 0.93; p = 0.02).
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In studies with patients with TB at baseline, the impact of MNS on mortality was a RR of 0.91 (0.64, 1.31, p = 0.62).
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We gratefully acknowledge the assistance of Maud Dupuy, Margaret Smirnoff, RN, FNP, MPH; Qian Zuo, PhD (Chinese translator), and Kirti Dasu.