Higher serum 25(OH)D concentration is associated with lower risk of chronic otitis media with effusion: a case-control study

Association Between Vitamin D and Novel SARS-CoV-2 Respiratory Dysfunction - A Scoping Review of Current Evidence and Its Implication for COVID-19 Pandemic

OBJECTIVES

To assess the association between vitamin D deficiency and increased morbidity/mortality with COVID-19 respiratory dysfunction.

DESIGN

Scoping review.

DATA SOURCES

Ovid MEDLINE (1946 to 24 of April 2020) and PubMed (2020 to 17 of September 2020).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

A search using the search terms: [(cholecalciferol or ergocalciferol or vitamin D2 or vitamin D3 or vitamin D or 25OHD) and (SARS-CoV-2 or coronavirus or COVID or betacoronavirus or MERS-CoV or SARS-CoV or respiratory infection or acute respiratory distress syndrome or ARDS)]m.p. was conducted on the 24/04/2020 (Search A) and 17/09/2020 (Search B).

RESULTS

91 studies were identified as being concerned with Acute Respiratory Infection (ARI)/Acute Respiratory Distress Syndrome (ARDS) and vitamin D, and 25 publications specifically explored the role of vitamin D deficiency in the development and progression of SARS-CoV-2/COVID-19 related ARDS. Search "A" identified three main themes of indirect evidence supporting such an association. Consistent epidemiological evidence exists linking low vitamin D levels to increased risk and severity of respiratory tract infections. We also report on plausible biological processes supporting such an association; and present weaker evidence supporting the benefit of vitamin D supplementation in reducing the risk and severity of ARIs. Uncertainty remains about what constitutes an appropriate dosing regimen in relation to reducing risk/severity of ARI/ARDS. More recent evidence (Search B) provided new insights into some direct links between vitamin D and COVID-19; with a number of cohort and ecological studies supporting an association with PCR-positivity for SARS-CoV-2 and vitamin D deficiency. The exact efficacy of the vitamin D supplementation for prevention of, or as an adjunct treatment for COVID-19 remains to be determined; but a number of randomized control trials (RCTs) currently underway are actively investigating these potential benefits.

CONCLUSION

Our rapid review of literature supports the need for observational studies with COVID-19 infected populations to measure and assess vitamin D levels in relation to risk/severity and outcomes; alongside RCTs designed to evaluate the efficacy of supplementation both in preventive and therapeutic contexts. The overlap in the vitamin D associated biological pathways with the dysregulation reported to drive COVID-19 outcomes warrants further investigation.

The association between vitamin D status and infectious diseases of the respiratory system in infancy and childhood

PURPOSE

Respiratory tract infections (RTIs) are a major cause of illness worldwide and the most common cause of hospitalization for pneumonia and bronchiolitis. These two diseases are the leading causes of morbidity and mortality among children under 5 years of age. Vitamin D is believed to have immunomodulatory effects on the innate and adaptive immune systems by modulating the expression of antimicrobial peptides, like cathelicidin, in response to both viral and bacterial stimuli. The aim of this review is to summarize the more recently published data with regard to potential associations of 25-hydroxyvitamin D [25(OH)D] with infectious respiratory tract diseases of childhood and the possible health benefits from vitamin D supplementation.

METHODS

The literature search was conducted by using the PubMed, Scopus, and Google Scholar databases, with the following keywords: vitamin D, respiratory tract infection, tuberculosis, influenza, infancy, and childhood.

RESULTS

Several studies have identified links between inadequate 25(OH)D concentrations and the development of upper or lower respiratory tract infections in infants and young children. Some of them also suggest that intervention with vitamin D supplements could decrease both child morbidity and mortality from such causes.

CONCLUSIONS

Most studies agree in that decreased vitamin D concentrations are prevalent among most infants and children with RTIs. Also, normal to high-serum 25(OH)D appears to have some beneficial influence on the incidence and severity of some, but not all, types of these infections. However, studies with vitamin D supplementation revealed conflicting results as to whether supplementation may be of benefit, and at what doses.

Vitamin D and Otitis Media

PURPOSE OF REVIEW

To examine the relationship between vitamin D and otitis media.

RECENT FINDINGS

Vitamin D deficiency has been associated with several respiratory diseases, including otitis media. Vitamin D supplementation may reduce the risk of otitis media. This relationship may be explained by vitamin D supporting the immune system by upregulating antimicrobial peptides which are effective against otopathogens and biofilm formation, supporting a less inflammatory immune response, or promoting beneficial commensal bacteria. This review will explore risk factors of both otitis media and vitamin D deficiency, the evidence of vitamin D being beneficial for various forms of otitis media, and possible mechanisms of action.

Is there an association between vitamin D deficiency and adenotonsillar hypertrophy in children with sleep-disordered breathing?

BACKGROUND

Low vitamin D levels have been linked to the risk of sleep-disordered breathing (SDB) in children. Although adenotonsillar hypertrophy (ATH) is the major contributor to childhood SDB, the relationship between ATH and serum vitamin D is uncertain. We therefore investigated the relationship between vitamin D levels and associated factors in children with ATH.

METHODS

We reviewed data from all children with SDB symptoms who were treated from December 2013 to February 2014. Of these, 88 children whose serum vitamin D levels were measured were enrolled in the study. We divided the children into four groups based on adenoidal and/or tonsillar hypertrophy. We conducted a retrospective chart review to analyze demographic data, the sizes of tonsils and adenoids, serum 25-hydroxy-vitamin D [25(OH)D] level, body mass index (BMI), and allergen sensitization patterns.

RESULTS

Children in the ATH group had a lower mean 25(OH)D level than did those in the control group (p < 0.05). Children with vitamin D deficiencies exhibited markedly higher frequencies of adenoidal and/or tonsillar hypertrophy than did those with sufficient vitamin D (p < 0.05). Spearman's correlation analysis identified an inverse correlation between serum 25(OH)D levels and age, tonsil and adenoid size, and height (all p < 0.05). In a multiple regression analysis, tonsil and adenoid size as well as BMI-z score, were associated with 25(OH)D levels after controlling for age, sex, height, and mite sensitization (p < 0.05).

CONCLUSIONS

Our results suggest that low vitamin D levels are linked to ATH. Both the sizes of the adenoids and tonsils and the BMI-z score were associated with the 25(OH)D level. Therefore, measurement of the serum 25(OH)D level should be considered in children with ATH and SDB symptoms.

Influence of Vitamin D Deficiency on Progression of Experimental Otitis Media in Rats

BACKGROUND

Vitamin D plays an important role in the immune response against infection. The purpose of the present study was to investigate the influence of vitamin D deficiency on the progression of otitis media (OM) using an experimental rat model.

METHODS

Four-week-old male Sprague-Dawley rats (n=72) were divided into two groups based on their diet: a control diet group (n=36) and a vitamin D-deficient diet group (n=36). After 8 weeks of diet, experimental OM was induced by inoculation of non-typeable Haemophilus influenzae in the middle ear cavity. The rats were evaluated with otomicroscopy to determine the inflammation in the middle ear mucosa on days 1, 2, 4, 7, and 14 post-inoculation. Bullae from sacrificed rats were collected and analyzed histologically.

RESULTS

The middle ear mucosa from rats with vitamin D deficiency showed a significantly higher thickness than that of controls during the course of OM. The maximum mucosal thickness was 56.0±9.1 μm in the vitamin D deficiency group, and 43.9±9.8 μm in the control group, although there was no significant difference in the tympanic membrane score between the two groups evaluated with otomicroscopy. An immunohistochemical study showed increased expression of interleukin 6 (IL-6) and tumor necrosis factor α in rats manifesting vitamin D deficiency and decreased expression of IL-10 compared with controls.

CONCLUSION

Our results showed that vitamin D deficiency may exacerbate the pathophysiological changes of OM via altered cytokine production. Therefore, maintaining vitamin D status in the optimal range may be beneficial for proper management of OM.

Clinical role of vitamin D in prognosis of otitis media with effusion

OBJECTIVE

To investigate the clinical role of Vitamin D in prognosis of Otitis media with effusion.

METHODS

This prospective-controlled study was conducted at otolaryngology department in Duzce University, Turkey. The study group comprised children who were diagnosed with Otitis media with effusion between September 2016 and February 2017. Control group was conducted with children underwent circumcision or inguinal hernia repair operations that confirmed with ENT examination they do not have any sign of otitis media. After 3 months of follow-up without any treatment, unresolved cases who were accepted as chronic otitis media with effusion were operated under general anesthesia for ventilation tube application. Study and control groups were assessed depending on the serum 25(OH)Vitamin D levels at the end of 3 months; < 15 ng/mL was accepted as vitamin D deficiency. The results were compared with the control group in terms of vitamin D levels. Also, subgroup analysis was performed addressing to the complete recovery otitis media with effusion and chronic otitis media with effusion.

RESULTS

One-hundred-seventy-four children with otitis media with effusion and 80 control patients were included to the study. One-hundred-eight (62%) out of 174 patients with otitis media with effusion was completely recovered after a 3-months follow up. Of those 66 out of 174 children, they had persistent diseases, underwent ventilation tube insertion after a 3-months follow-up. The mean 25(OH)Vitamin D level was 18.98 ± 10.60 in otitis media with effusion group and 28.07 ± 14.10 in control group and the difference was statistically significant between the study and control group (p < 0.001). Vitamin D deficiency was observed in 33 out of 66 patients (50.0%) in chronic otitis media with effusion group whilst 35 out of 108 patients (32.4%) in complete recovery otitis media with effusion group (p = 0.021). The rate of 25(OH)Vitamin D deficiency was 25% in control group which was statistically different from chronic otitis media with effusion and recovery chronic otitis media with effusion groups (p = 0.006).

CONCLUSIONS

This study not only shows the relationship between Vitamin D and otitis media with effusion development, but also demonstrates the effects of Vitamin D on otitis media with effusion prognosis. There is a significant association between 25(OH)Vitamin D deficiency and follow-up outcomes of otitis media with effusion.