Vitamin D supplementation improves well-being in patients with frequent respiratory tract infections: a post hoc analysis of a randomized, placebo-controlled trial.
BMC Res Notes. 2015 Sep 29;8:498. doi: 10.1186/s13104-015-1504-2.
Bergman P1, Norlin AC2, Hansen S3, Björkhem-Bergman L4.
1Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Huddinge, 141 86, Stockholm, Sweden. peter.bergman at ki.se.
2Division of Clincal Immunology, Karolinska Institutet, Karolinska University Hospital Huddinge, 141 86, Stockholm, Sweden. anna-carin.norlin at karolinska.se.
3Infectious Disease Clinic, Karolinska University Hospital, 141 86, Stockholm, Sweden. susanne.hansen at karolinska.se.
4Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Huddinge, 141 86, Stockholm, Sweden. linda.bjorkhem-bergman at ki.se.
RCT with 4,000 IU of vitamin D daily for a year
It appears that the study found (compared to placebo)
43% more likely to feel better if > 40 ng
30% more likely to feel better independent of vitamin D level achieved
22% more likely to feel better if < 40 ng
This study, like most vitamin D studies, did not look at the interaction with genes.
Rather than a 2X increase associated with Vitamin D level ,might expect > 4X increase associated with a gene or 2
See also VitaminDWiki
- Respiratory tract infections in childhood – vitamin D is needed, no consensus of how much – Oct 2015
- Respiratory Tract visits 2.5 less likely with vitamin D: Pregnancy 2000 IU, Infant 800 IU – RCT Oct 2014 Why not eliminate the RTI by taking vitamin D ahead of time?
- Respiratory infections cut in half by 20,000 IU weekly vitamin D if initially deficient – RCT March 2015
- Respiratory tract infection eliminated in 36 percent of people by 4000 IU of Vitamin D – RCT Sept 2015 Previous analysis of data by the authors
- Search "Respiratory Tract Infection" 413 items as of July 2017
The aim of this study was to test the hypothesis that vitamin D supplementation improves well-being in patients with frequent respiratory tract infections (RTIs). We performed a post hoc analysis of a randomized, placebo-controlled and double-blind study in which patients with frequent RTIs were randomized to placebo or vitamin D (4000 IE/day for 1 year, n = 124). At the last visit of the study, patients were asked to perform a general assessment of their well-being during the study.
The majority of patients, both placebo- and vitamin D treated, stated that they had felt 'better' during the study; 52% in the placebo group and 70% in the vitamin D group, relative risk 1.3 (95% CI 1.0-1.8; p = 0.06, Fisher's exact test). Statement of better well-being was associated with an increase in 25-hydroxyvitamin D (25-OHD) levels (p < 0.001). In contrast, worse well-being was associated with unchanged 25-OHD levels. Notably, a 25-OHD level above 100 nmol/L at the study end was associated with a higher chance of having a better well-being (p < 0.01). Four patients on anti-depressive treatment could terminate their antidepressant medication during the study. These patients had a significant increase in 25-OHD levels from low levels at study-start.
Vitamin D supplementation to patients with frequent RTIs might be beneficial, not only for infections, but also for their general well-being. However, given the post hoc design of this study, these findings need to be confirmed in additional clinical trials before firm conclusions can be drawn.
http://www.clinicaltrials.gov (NCT01131858), registered March 22, 2010.