tetano
Editor, Senior Moderator
JAMA. 2017 Jul 18;318(3):245-254. doi: 10.1001/jama.2017.8708.
[h=1]Effect of High-Dose vs Standard-Dose Wintertime Vitamin D Supplementation on Viral Upper Respiratory Tract Infections in Young Healthy Children.[/h] Aglipay M[SUP]1[/SUP], Birken CS[SUP]2[/SUP], Parkin PC[SUP]2[/SUP], Loeb MB[SUP]3[/SUP], Thorpe K[SUP]4[/SUP], Chen Y[SUP]5[/SUP], Laupacis A[SUP]6[/SUP], Mamdani M[SUP]5[/SUP], Macarthur C[SUP]2[/SUP], Hoch JS[SUP]7[/SUP], Mazzulli T[SUP]8[/SUP], Maguire JL[SUP]9[/SUP]; TARGet Kids! Collaboration.
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]Importance:[/h] Epidemiological studies support a link between low 25-hydroxyvitamin D levels and a higher risk of viral upper respiratory tract infections. However, whether winter supplementation of vitamin D reduces the risk among children is unknown.
[h=4]Objective:[/h] To determine whether high-dose vs standard-dose vitamin D supplementation reduces the incidence of wintertime upper respiratory tract infections in young children.
[h=4]Design, Setting, and Participants:[/h] A randomized clinical trial was conducted during the winter months between September 13, 2011, and June 30, 2015, among children aged 1 through 5 years enrolled in TARGet Kids!, a multisite primary care practice-based research network in Toronto, Ontario, Canada.
[h=4]Interventions:[/h] Three hundred forty-nine participants were randomized to receive 2000 IU/d of vitamin D oral supplementation (high-dose group) vs 354 participants who were randomized to receive 400 IU/d (standard-dose group) for a minimum of 4 months between September and May.
[h=4]Main Outcome Measures:[/h] The primary outcome was the number of laboratory-confirmed viral upper respiratory tract infections based on parent-collected nasal swabs over the winter months. Secondary outcomes included the number of influenza infections, noninfluenza infections, parent-reported upper respiratory tract illnesses, time to first upper respiratory tract infection, and serum 25-hydroxyvitamin D levels at study termination.
[h=4]Results:[/h] Among 703 participants who were randomized (mean age, 2.7 years, 57.7% boys), 699 (99.4%) completed the trial. The mean number of laboratory-confirmed upper respiratory tract infections per child was 1.05 (95% CI, 0.91-1.19) for the high-dose group and 1.03 (95% CI, 0.90-1.16) for the standard-dose group, for a between-group difference of 0.02 (95% CI, -0.17 to 0.21) per child. There was no statistically significant difference in number of laboratory-confirmed infections between groups (incidence rate ratio [RR], 0.97; 95% CI, 0.80-1.16). There was also no significant difference in the median time to the first laboratory-confirmed infection: 3.95 months (95% CI, 3.02-5.95 months) for the high-dose group vs 3.29 months (95% CI, 2.66-4.14 months) for the standard-dose group, or number of parent-reported upper respiratory tract illnesses between groups (625 for high-dose vs 600 for standard-dose groups, incidence RR, 1.01; 95% CI, 0.88-1.16). At study termination, serum 25-hydroxyvitamin D levels were 48.7 ng/mL (95% CI, 46.9-50.5 ng/mL) in the high-dose group and 36.8 ng/mL (95% CI, 35.4-38.2 ng/mL) in the standard-dose group.
[h=4]Conclusions and Relevance:[/h] Among healthy children aged 1 to 5 years, daily administration of 2000 IU compared with 400 IU of vitamin D supplementation did not reduce overall wintertime upper respiratory tract infections. These findings do not support the routine use of high-dose vitamin D supplementation in children for the prevention of viral upper respiratory tract infections.
[h=4]Trial Registration:[/h] clinicaltrials.gov Identifier: NCT01419262.
PMID: 28719693 DOI: 10.1001/jama.2017.8708
[h=1]Effect of High-Dose vs Standard-Dose Wintertime Vitamin D Supplementation on Viral Upper Respiratory Tract Infections in Young Healthy Children.[/h] Aglipay M[SUP]1[/SUP], Birken CS[SUP]2[/SUP], Parkin PC[SUP]2[/SUP], Loeb MB[SUP]3[/SUP], Thorpe K[SUP]4[/SUP], Chen Y[SUP]5[/SUP], Laupacis A[SUP]6[/SUP], Mamdani M[SUP]5[/SUP], Macarthur C[SUP]2[/SUP], Hoch JS[SUP]7[/SUP], Mazzulli T[SUP]8[/SUP], Maguire JL[SUP]9[/SUP]; TARGet Kids! Collaboration.
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]Importance:[/h] Epidemiological studies support a link between low 25-hydroxyvitamin D levels and a higher risk of viral upper respiratory tract infections. However, whether winter supplementation of vitamin D reduces the risk among children is unknown.
[h=4]Objective:[/h] To determine whether high-dose vs standard-dose vitamin D supplementation reduces the incidence of wintertime upper respiratory tract infections in young children.
[h=4]Design, Setting, and Participants:[/h] A randomized clinical trial was conducted during the winter months between September 13, 2011, and June 30, 2015, among children aged 1 through 5 years enrolled in TARGet Kids!, a multisite primary care practice-based research network in Toronto, Ontario, Canada.
[h=4]Interventions:[/h] Three hundred forty-nine participants were randomized to receive 2000 IU/d of vitamin D oral supplementation (high-dose group) vs 354 participants who were randomized to receive 400 IU/d (standard-dose group) for a minimum of 4 months between September and May.
[h=4]Main Outcome Measures:[/h] The primary outcome was the number of laboratory-confirmed viral upper respiratory tract infections based on parent-collected nasal swabs over the winter months. Secondary outcomes included the number of influenza infections, noninfluenza infections, parent-reported upper respiratory tract illnesses, time to first upper respiratory tract infection, and serum 25-hydroxyvitamin D levels at study termination.
[h=4]Results:[/h] Among 703 participants who were randomized (mean age, 2.7 years, 57.7% boys), 699 (99.4%) completed the trial. The mean number of laboratory-confirmed upper respiratory tract infections per child was 1.05 (95% CI, 0.91-1.19) for the high-dose group and 1.03 (95% CI, 0.90-1.16) for the standard-dose group, for a between-group difference of 0.02 (95% CI, -0.17 to 0.21) per child. There was no statistically significant difference in number of laboratory-confirmed infections between groups (incidence rate ratio [RR], 0.97; 95% CI, 0.80-1.16). There was also no significant difference in the median time to the first laboratory-confirmed infection: 3.95 months (95% CI, 3.02-5.95 months) for the high-dose group vs 3.29 months (95% CI, 2.66-4.14 months) for the standard-dose group, or number of parent-reported upper respiratory tract illnesses between groups (625 for high-dose vs 600 for standard-dose groups, incidence RR, 1.01; 95% CI, 0.88-1.16). At study termination, serum 25-hydroxyvitamin D levels were 48.7 ng/mL (95% CI, 46.9-50.5 ng/mL) in the high-dose group and 36.8 ng/mL (95% CI, 35.4-38.2 ng/mL) in the standard-dose group.
[h=4]Conclusions and Relevance:[/h] Among healthy children aged 1 to 5 years, daily administration of 2000 IU compared with 400 IU of vitamin D supplementation did not reduce overall wintertime upper respiratory tract infections. These findings do not support the routine use of high-dose vitamin D supplementation in children for the prevention of viral upper respiratory tract infections.
[h=4]Trial Registration:[/h] clinicaltrials.gov Identifier: NCT01419262.
PMID: 28719693 DOI: 10.1001/jama.2017.8708