Vitamin D in Moderation Reduces Risk of Acute Respiratory Infections

Sarfaroj Khan 

Disclosures

April 07, 2021

Takeaway

  • This meta-analysis found a small but significant protective effect of vitamin D supplementation on the risk of having ≥1 acute respiratory infections (ARIs) vs placebo, but there was evidence of significant heterogeneity of effect across trials.

  • Protection was associated with administration of daily doses of 400-1000 international units (IU) for up to 12 months and age at enrolment of 1.00-15.99 years.

Why this matters

  • A 2017 meta-analysis of data from 25 randomised controlled trials (RCTs) of vitamin D supplementation for the prevention of ARIs showed a protective effect of this intervention.

  • The relevance of these findings to COVID-19 is not known and requires further investigation.

Study design

  • Meta-analysis of 43 RCTs including 49,419 participants.

  • Funding: None.

Key results

  • A significantly lower proportion of participants in the vitamin D supplementation group had ≥1 ARIs vs placebo group (61.3% vs 62.3%; OR, 0.92; 95% CI, 0.86-0.99; 37 studies; I²=35.6%; Pheterogeneity=.018).

  • No significant effect of vitamin D supplementation on the risk of having ≥1 ARIs was seen for any of the subgroups defined by baseline 25(OH)D concentration.

  • A significant protective effect of vitamin D supplementation was seen in trials in which vitamin D was given (OR; 95% CI):

    • in a daily dosing regimen (0.78; 0.65-0.94; 19 studies; I²=53.5%, Pheterogeneity=.003);

    • at daily dose equivalents of 400-1000 IU (0.70; 0.55-0.89; 10 studies; I²=31.2%, Pheterogeneity=.16);

    • for a duration of ≤12 months (0.82; 0.72-0.93; 29 studies; I²=38.1%; Pheterogeneity=.021); and

    • to participants aged 1.00-15.99 years at enrolment (0.71; 0.57-0.90; 15 studies; I²=46.0%; Pheterogeneity=.027).

  • No significant interaction was seen between allocation to the vitamin D
    supplementation group vs the placebo group and dose, dose frequency, study duration, or age.

Limitations

  • Heterogeneity across trials.

  • Risk of bias.

 

Jolliffe DA, Camargo CA, Sluyter JD, Aglipay M, Aloia JF, Ganmaa D, Bergman P, Bischoff-Ferrari HA, Borzutzky A, Damsgaard CT, Dubnov-Raz G, Esposito S, Gilham C, Ginde AA, Golan-Tripto I, Goodall EC, Grant CC, Griffiths CJ, Hibbs AM, Janssens W, Khadilkar AV, Laaksi I, Lee MT, Loeb M, Maguire JL, Majak P, Mauger DT, Manaseki-Holland S, Murdoch DR, Nakashima A, Neale RE, Pham H, Rake C, Rees JR, Rosendahl J, Scragg R, Shah D, Shimizu Y, Simpson-Yap S, Trilok-Kumar G, Urashima M, Martineau AR. Vitamin D supplementation to prevent acute respiratory infections: a systematic review and meta-analysis of aggregate data from randomised controlled trials. Lancet Diabetes Endocrinol. 2021 Mar 30 [Epub ahead of print]. doi: 10.1016/S2213-8587(21)00051-6. PMID: 33798465.  View full text 

This clinical summary originally appeared on Univadis, part of the Medscape Professional Network.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....