Nnoaham, K. E. & Clarke, A. Low serum vitamin D levels and tuberculosis: a systematic review and meta-analysis. Int. J. Epidemiol. 37, 113-119

Department of Public Health, Oxfordshire Primary Care Trust, Richard Building, Old Road Campus, Headington, Oxford OX3 7LG, UK.
International Journal of Epidemiology (Impact Factor: 9.18). 03/2008; 37(1):113-9. DOI: 10.1093/ije/dym247
Source: PubMed


To explore the association between low serum vitamin D and risk of active tuberculosis in humans.
Systematic review and meta-analysis.
Observational studies published between 1980 and July 2006 (identified through Medline) that examined the association between low serum vitamin D and risk of active tuberculosis.
For the review, seven papers were eligible from 151 identified in the search. The pooled effect size in random effects meta-analysis was 0.68 with 95% CI 0.43-0.93. This 'medium to large' effect represents a probability of 70% that a healthy individual would have higher serum vitamin D level than an individual with tuberculosis if both were chosen at random from a population. There was little heterogeneity between the studies.
Low serum vitamin D levels are associated with higher risk of active tuberculosis. Although more prospectively designed studies are needed to firmly establish the direction of this association, it is more likely that low body vitamin D levels increase the risk of active tuberculosis. In view of this, the potential role of vitamin D supplementation in people with tuberculosis and hypovitaminosis D-associated conditions like chronic kidney disease should be evaluated.

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Available from: Kelechi Ebere Nnoaham, Jul 12, 2014
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    • "It has been shown that vitamin D deficiency [8] (serum 25(OH)D level <20 ng/mL or <50 nmol/L) and insufficiency [8] (serum 25(OH)D level <30 ng/mL or <75 nmol/L) are associated with a higher risk of active TB [9], suggesting that low serum 25(OH)D levels may also lead to prolonged clinical course of the disease if not corrected. Therefore, it is appropriate to surmise that individuals with higher levels of circulating 25(OH)D are associated with better outcomes with regard to TB, as reported in a previously conducted systematic review and meta-analysis of seven observational studies [10]. Along those lines, it can be assumed that increasing vitamin D intake would help protect against TB, but in reality this is not always the case. "
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    ABSTRACT: Objective To investigate the impacts of vitamin D status, supplementation and vitamin D receptor (VDR) gene polymorphisms on tuberculosis (TB). Methods We conducted a systematic review of published studies pertaining to case-control and randomized-control trials from 2002 to 2014 using the PubMed database. Results and conclusion: Individuals with TB have lower vitamin D status than healthy individuals. Some VDR gene polymorphisms are associated with increased susceptibility to TB while others may not. Supplementation with vitamin D leads to improved clinical outcomes. However, further studies with a larger patient population and different ethnicities are needed to confirm these effects.
    Journal of Clinical and Translational Endocrinology 12/2014; 1(4). DOI:10.1016/j.jcte.2014.08.001
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    • "" This health claim is targeting men and women 60 years of age and older and the dose required is a daily consumption of 800 IU vitamin D, which can come from all sources. Further emerging vitamin D health relationships include physiological parameters like improved immune response (Baeke et al., 2010; Schwalfenberg, 2011; Hewison, 2012; White, 2012), improved respiratory health(Berry et al., 2011; Charan et al., 2012; Choi et al., 2013; Hirani, 2013) possibly also relate to reduced tuberculosis incidence (Nnoaham and Clarke, 2008; Martineau et al., 2011; Mitchell et al., 2011; Coussens et al., 2012; Salahuddin et al., 2013; Huaman et al., 2014); and reduced risk to develop autoimmune diseases like multiple sclerosis (Solomon and Whitham, 2010; Cantorna, 2012; Dobson et al., 2013) or type 1 diabetes (Hypponen et al., 2001; Holick, 2003; Ramos-Lopez et al., 2006; Baeke et al., 2010; De Boer et al., 2012; Dong et al., 2013; Van Belle et al., 2013). In chronic, non-communicable diseases, vitamin D deficiency is being discussed to possibly ameliorate the incidence of some neoplastic diseases like colorectal, lung, prostate, and breast cancers (Ng et al., 2008; Rosen et al., 2012; Welsh, 2012; Cheng et al., 2013); cardiovascular diseases (CVDs) including hypertension, myocardial infarction, stroke (Forman et al., 2007; Giovannucci et al., 2008; Gardner et al., 2011; Bischoff-Ferrari et al., 2012; Tamez and Thadhani, 2012; Karakas et al., 2013; Pilz et al., 2013a; Schroten et al., 2013); life-style diseases like obesity and type 2 diabetes (Pittas et al., 2007; González-Molero et al., 2012; Khan et al., 2013; Pilz et al., 2013b; Schottker et al., 2013; Tsur et al., 2013; Van Belle et al., 2013; Bouillon et al., 2014); diseases related to the decline in sight function including age-related macular degeneration (Parekh et al., 2007; Millen et al., 2011; Lee et al., 2012); and neurological disorders including Alzheimer and Parkinson disease (Buell and Dawson-Hughes, 2008; Annweiler et al., 2012; Eyles et al., 2013; Zhao et al., 2013). "
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    ABSTRACT: Vitamin D is a micronutrient that is needed for optimal health throughout the whole life. Vitamin D3 (cholecalciferol) can be either synthesized in the human skin upon exposure to the UV light of the sun, or it is obtained from the diet. If the photoconversion in the skin due to reduced sun exposure (e.g. in wintertime) is insufficient, intake of adequate vitamin D from the diet is essential to health. Severe vitamin D deficiency can lead to multitude of avoidable illnesses; among them are well known bone diseases like osteoporosis, a number of autoimmune diseases, many different cancers and some cardiovascular diseases like hypertension are being discussed. Vitamin D is found naturally in only very few foods. Foods containing vitamin D include some fatty fish, fish liver oils, and eggs from hens that have been fed vitamin D and some fortified foods in countries with respective regulations. Base on geographic location or food availability adequate vitamin D intake might not be sufficient on a global scale. The International Osteoporosis Foundation (IOF) has collected the 25-hydroxy-vitamin D plasma levels in populations of different countries using published data and developed a global vitamin D map. This map illustrates the parts of the world, where vitamin D did not reach adequate 25-hydroxyvitamin D plasma levels: 6.7 % of the papers report 25-hydroxyvitamin D plasma levels below 25 nmol/L, which indicates vitamin D deficiency, 37.3 % are below 50 nmol/Land only 11.9% found 25-hydroxy-vitamin D plasma levels above 75 nmol/L target as suggested by vitamin D experts. The vitamin D map is adding further evidence to the vitamin D insufficiency pandemic debate, which is also an issue in the developed world. Besides malnutrition, a condition where the diet does not match to provide the adequate levels of nutrients including micronutrients for growth and maintenance, we obviously have a situation where enough nutrients were consumed, but lacked to reach sufficient vitam
    Frontiers in Physiology 07/2014; 5:248. DOI:10.3389/fphys.2014.00248 · 3.53 Impact Factor
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    • "In recent years vitamin D has become a buzzword in disease prevention and treatment. There is an ever-expanding list of communicable and noncommunicable diseases being associated with vitamin D deficiency, including types 1 and 2 diabetes mellitus, rheumatoid arthritis, cardiovascular disease, osteoporosis, multiple sclerosis, depression, irritable bowel disease, asthma, colorectal, lung and breast cancers, upper respiratory tract infections, tuberculosis (TB), and HIV/AIDS progression and mortality [1–6]. No longer is vitamin D considered solely a regulator of calcium and bone homoeostasis; it is now recognized to have a diverse range of physiological functions, including cellular differentiation, proliferation, activation, and death [7]. "
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    ABSTRACT: Tuberculosis (TB) disease activation is now believed to arise due to a lack of inflammatory homeostatic control at either end of the spectrum of inflammation: either due to immunosuppression (decreased antimicrobial activity) or due to immune activation (excess/aberrant inflammation). Vitamin D metabolites can increase antimicrobial activity in innate immune cells, which, in the context of HIV-1 coinfection, have insufficient T cell-mediated help to combat Mycobacterium tuberculosis (MTB) infection. Moreover, maintaining vitamin D sufficiency prior to MTB infection enhances the innate antimicrobial response to T cell-mediated interferon- γ . Conversely, vitamin D can act to inhibit expression and secretion of a broad range of inflammatory mediators and matrix degrading enzymes driving immunopathology during active TB and antiretroviral- (ARV-) mediated immune reconstitution inflammatory syndrome (IRIS). Adjunct vitamin D therapy during treatment of active TB may therefore reduce lung pathology and TB morbidity, accelerate resolution of cavitation and thereby decrease the chance of transmission, improve lung function following therapy, prevent relapse, and prevent IRIS in those initiating ARVs. Future clinical trials of vitamin D for TB prevention and treatment must be designed to detect the most appropriate primary endpoint, which in some cases should be anti-inflammatory and not antimicrobial.
    07/2014; 2014(12):903680. DOI:10.1155/2014/903680
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