Thread by @DrSubhasree

#VitaminD and Respiratory illness: Why D is crucial in #COVID19 management?

Evidence on Vitamin D physiology has revealed that Vitamin D not just plays a role in calcium homeostasis but a crucial component to prevent respiratory illnesses.

Thread with 12 studies.

1. Respiratory Tract Infection:

A. A study from India involving 80 cases & 70 controls, aged 2-60 months concluded that subclinical D def. & nonexclusive breastfeeding were significant risk factors for severe Acute Lower Respiratory Tract Infection.
nature.com/articles/16018…

1.B. Epidemic Influenza: Hope-Simpson hypothesized that solar radiation produced a ‘seasonal stimulus’ that profoundly affected the pathogenesis of influenza A.
ncbi.nlm.nih.gov/pmc/articles/P…

1.C. A study with 800 young Finnish military men revealed that 24 men with serum 25(OH)D concentrations < 40 nmol/L had significantly (P = 0.004) more days of absence from duty due to respiratory infection than did control subjects (n = 628).
pubmed.ncbi.nlm.nih.gov/17823437/

1.D. A survey to find out the association between Vit-D level & UTRI in 18883 12 yrs & older participants, revealed 24% of participants with 25(OH)D levels <10 ng/mL, 20% with levels of 10 to <30 ng/mL, & 17% with levels of 30 ng/mL or more (P<.001).
jamanetwork.com/journals/jamai…

2. Tuberculosis:

A. A hospital-based case-control analysis of Asians of Gujarati origin, a mainly vegetarian immigrant population with a high rate of tuberculosis reported 25(OH)D deficiency was associated with active tuberculosis (p=0.008).
thelancet.com/journals/lance…

2.B. Vitamin D receptor (VDR) gene polymorphisms have been implicated in susceptibility to TB. FokI, BsmI, ApaI, and TaqI polymorphism in 1139 case-patients & control subjects & 382 families from Africa reported a significant association between SNPs & TB.
academic.oup.com/jid/article/19…

2.C. 1α,25 dihydroxyvitamin D3 (1α,25(OH)2D3), modulates the immune response to Mycobacterium tuberculosis (MTB). A study by Martineau et al describes “nonclassical” mechanisms of Vit-D protection, including the induction of antimicrobial peptides.
jimmunol.org/content/178/11…

2.D. An RCT involving 192 healthy adult TB contacts in London, received a single oral dose of 2.5 (n=96) mg D or placebo (n=96) reported significantly enhanced ability in D group's whole blood to restrict BCG-lux luminescence in compared to the placebo.
pubmed.ncbi.nlm.nih.gov/17463418/

3. Asthma and COPD:

A. Chronic obstructive pulmonary disease (COPD) is a candidate disease for which vitamin D supplementation might be beneficial.
atsjournals.org/doi/abs/10.116…

3.B. Forli and colleagues found vitamin D deficiency (<20 ng/ml) in more than 50% of a cohort waiting for lung transplantation.
onlinelibrary.wiley.com/doi/full/10.11…

3.C. An observational study involving 1024 children with mild-to-moderate persistent asthma at the time of enrollment find that 35% were vitamin D insufficient with a higher odds of any hospitalization or emergency department visit (p=0.01).
pubmed.ncbi.nlm.nih.gov/20538327/

3.D. A study with 54 non-smoking adults with asthma reported higher vitamin D levels were associated with greater lung function. Participants with vitamin D insufficiency (<30 ng/ml) demonstrated increased airway hyperresponsiveness.
pubmed.ncbi.nlm.nih.gov/20075384/

This thread is inspired by @Tweet_Nutrition. She shared an excellent review day before yesterday. Thank you.

@NickdeCusa @deNutrients @deboraha_rd @chitguppi @Thinkerks @DonaldJ48630478 @AndrewJacksonV3