Randomized Trial of Vitamin D Supplementation to Prevent Seasonal Influenza and Upper Respiratory Infection in Patients With Inflammatory Bowel Disease

Abstract

Background We evaluated whether oral vitamin D supplementation during the winter and early spring reduces the incidence of influenza and upper respiratory infections in patients with inflammatory bowel disease (IBD). Methods A randomized, double-blind, controlled trial was conducted to compare the effects of vitamin D supplementation (500 IU/day) and a placebo. The primary outcome was the incidence of influenza; the secondary outcome was the incidence of upper respiratory infection. Prespecified subgroup analyses were performed according to 25-hydroxyvitamin D (25-OHD) levels (low <20 ng/mL or high ≥20 ng/mL) and whether ulcerative colitis (UC) or Crohn’s disease (CD) was present. We also used the Lichtiger clinical activity index for patients with UC and the Crohn’s Disease Activity Index (CDAI) for patients with CD before and after interventions. Results We included 223 patients with IBD and randomized them into 2 groups: vitamin D supplementation (n = 108) and placebo (n = 115). The incidence of influenza did not differ between the groups. However, the incidence of upper respiratory infection was significantly lower in the vitamin D group (relative risk [RR], 0.59; 95% confidence interval (CI), 0.35–0.98; P = 0.042). This effect was enhanced in the low 25-OHD level subgroup (RR, 0.36; 95% CI, 0.14–0.90; P = 0.02). With respect to adverse events, the Lichtiger clinical activity index score was significantly worse in the vitamin D group ( P = 0.002) and remained significant only in the high 25-OHD level subgroup. Conclusions Vitamin D supplementation may have a preventative effect against upper respiratory infection in patients with IBD but may worsen the symptoms of UC.

The Role of Vitamin D in Combination Treatment for Patients With Rheumatoid Arthritis

“…A prior study suggested that the overall infection rate increased significantly during RA onset, and the antibacterial defense mechanism was defective (33). Recently, authors reported that VitD supplementation effectively reduced the incidence of acute cellular rejection and infection (34,35), upper respiratory infection (36,37) and acute respiratory infections (36,38). However, we obtained different results compared with the above studies.…”

25-Hydroxyvitamin D Concentrations Are Lower in Patients with Positive PCR for SARS-CoV-2

“…Despite the relatively low numbers, this evidence is particularly strong, since the group of PCR-negative patients had a risk of infection and symptoms of respiratory tract infections as indications for the PCR testing. Since the risk of symptomatic upper respiratory tract infection is suggested to be associated with low 25(OH)D levels [7], its concentration is expected to be quite low in PCR-negative patients (partially confirmed by the trend of a difference with the 2019 cohort, p = 0.076), making this control group even more stringent. Therefore, the significantly lower 25(OH)D concentrations in the PCR-positive group could indicate that the risk of SARS-CoV-2 infection has a stronger relationship with the 25(OH)D concentration, rather than other respiratory tract infections.…”

Impact of Serum 25(OH) Vitamin D Level on Mortality in Patients with COVID-19 in Turkey

“…We should take the effects of the lockdown and avoidance of sun exposure into account on the already insufficient 25(OH) vitamin D levels. Hypothesis regarding the potential deleterious roles of vitamin D deficiency on COVID-19 patients initially originated from the studies in which 25(OH) vitamin D was shown to be related to increased susceptibility to infection (25,26). However, some studies did not show the beneficial effects of vitamin D supplementation on the prevention and treatment of viral respiratory infections (27,28).…”