Vitamin D supplementation to patients with frequent respiratory tract infections: a post hoc analysis of a randomized and placebo-controlled trial.
BACKGROUNDVitamin D is considered to be important for a healthy immune system. The aim of this study was to test the hypothesis that vitamin D supplementation reduces number of respiratory tract infections (RTIs) and prolong the time to the first RTI in adult patients with frequent RTIs.
METHODSWe performed a post hoc analysis of a randomized, placebo-controlled and double-blinded study, where adult patients with a high burden of RTIs were randomized to placebo or vitamin D (4000 IE/day for 1 year, n = 124 in the per protocol cohort presented here).
RESULTSVitamin D supplementation increased the probability to stay free of RTI during the study year (RR 0.64, 95% CI 0.43-0.94). Further, the total number of RTIs was also reduced in the vitamin D-group (86 RTIs) versus placebo (120 RTIs; p = 0.05). Finally, the time to the first RTI was significantly extended in the vitamin D-group (HR 1.68, 95% CI 1.03-2.68, p = 0.0376).
CONCLUSIONVitamin D supplementation was found to significantly increase the probability of staying infection free during the study period. This finding further supports the notion that vitamin D-status should be monitored in adult patients with frequent RTIs and suggests that selected patients with vitamin D deficiency are supplemented. This could be a safe and cheap way to reduce RTIs and improve health in this vulnerable patient population. The original trial was registered at http://www.clinicaltrials.gov (NCT01131858).
Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital Huddinge, 141 86, Stockholm, Sweden. firstname.lastname@example.org.,
Division of Clincal Immunology, Karolinska Institutet and Karolinska University Hospital Huddinge, 141 86, Stockholm, Sweden. email@example.com.,
Infectious Disease Clinic, Karolinska University Hospital, 141 86, Stockholm, Sweden. firstname.lastname@example.org.
Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital Huddinge, 141 86, Stockholm, Sweden. email@example.com.
Respiratory Tract Infections
Pub Type(s)Journal Article
Randomized Controlled Trial
Research Support, Non-U.S. Gov't