An Observational Study on the Analysis of Vitamin D Deficiency in COVID-19 Patients With No Comorbidities: A Retrospective Analysis

Introduction: Vitamin D deficiency is an important problem when facing a viral disease. Vitamin D deficiency is widely prevalent in India and plays an important role in immunoregulation. The deficiency can lead to severe viral infections.

Aims and objectives: Vitamin D deficiency should be considered an independent risk factor in assessing the severity of COVID-19 infection. This study aims to establish this link. Our study is conducted with young individuals with no comorbidities. This has been done to exclusively evaluate vitamin D deficiency as an independent risk factor.

Methods: A retrospective record-based analysis was done on all patients with COVID-19 infection admitted at Max Smart Hospital, Saket, Delhi, from 1st September 2020 to 30th April 2022. Data gathering was done from 18th May 2023 to 30th May 2023. Vitamin D assay was checked as a part of routine care for all patients. The patients were divided into two groups. They consisted of vitamin D-sufficient and vitamin D-deficient patients. The primary endpoint was evaluated based on the outcomes, duration of stay, and severity of disease in these two groups.

Results: A total of 137 patients who met the inclusion criteria were included in the study. On presentation, 75.2% of patients had mild disease, 10.9% were classified as having moderate severity, and 13.9% had severe disease. The mean duration of hospital stay was 6.94±2.96 days. Vitamin D levels were normal in 31.4% (n=43) and vitamin D deficiency was noted in 68.6% (n=94) of patients. Vitamin D deficiency was reported in 64.9% (n=61, p-value=0.011) in the age group of <50 years and 35.1% (n=33, p-value=0.011) in the >50 years group. It was more frequently seen in male patients (67%, n=63, p-value=0.023) as compared to female patients (33%, n=31, p-value=0.023). Vitamin D deficiency was found in 74.5% (n=70, p-value=0.553) of patients with mild disease, 12.8% (n=12, p-value=0.553) with moderate-severity disease, and 12.8% (n=12, p-value=0.553) with severe disease. None of the patients with normal vitamin D levels required ICU admission on presentation. In the deficient group, 2.1% (n=2, p-value=0.335) of patients required ICU admission. The mean duration of hospital stay in the deficient group was 6.72±2.96 days (p-value=0.204). There was no mortality reported in this study.

Conclusion: Our study does show an increased incidence of moderate and severe disease in patients with vitamin D deficiency. This is in line with the evidence presented by several observational studies and meta-analyses. A specific randomized controlled trial focused on evaluating vitamin deficiency and the incidence of viral illness may be warranted to further evaluate this topic. Vitamin D deficiency is an easily correctable factor.