An investigation of the correlation of vitamin D status and management outcomes in patients with severe COVID-19 at a South African tertiary hospital

Thumeka P Jalavu; Lovemore N Sigwadhi; Maritha J Kotze; Anteneh Yalew; Vera Ngah; Jacques L Tamuzi; Zivanai C Chapanduka; Brian W Allwood; Coenraad F Koegelenberg; Elvis M Irusen; Usha Lalla; Tandi E Matsha; Rajiv T Erasmus; Ali Zumla; Annalise E Zemlin; Peter S Nyasulu

doi:10.1016/j.ijregi.2023.05.007

An investigation of the correlation of vitamin D status and management outcomes in patients with severe COVID-19 at a South African tertiary hospital

IJID Reg. 2023 Jun 1:8:121-128. doi: 10.1016/j.ijregi.2023.05.007. Online ahead of print.

Authors

Thumeka P Jalavu¹, Lovemore N Sigwadhi², Maritha J Kotze¹, Anteneh Yalew², Vera Ngah², Jacques L Tamuzi², Zivanai C Chapanduka³, Brian W Allwood⁴, Coenraad F Koegelenberg⁴, Elvis M Irusen⁴, Usha Lalla⁴, Tandi E Matsha^{5

6}, Rajiv T Erasmus¹, Ali Zumla⁷, Annalise E Zemlin¹, Peter S Nyasulu^{2

8}

Affiliations

¹ Division of Chemical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University & NHLS Tygerberg Hospital, Cape Town, South Africa.
² Division of Epidemiology and Biostatistics, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
³ Division of Haematological Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University & NHLS Tygerberg Hospital, Cape Town, South Africa.
⁴ Division of Pulmonology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University and Tygerberg Hospital, Cape Town, South Africa.
⁵ Sefako Makgatho Health Sciences University, Ga-Rankuwa, Pretoria, South Africa.
⁶ SAMRC/CPUT/Cardiometabolic Health Research Unit, Cape Peninsula University of Technology, Cape Town, South Africa.
⁷ Center for Clinical Microbiology, Division of Infection and Immunity, University College London, NIHR Biomedical Research Centre, UCL Hospitals NHS Foundation Trust, London, United Kingdom.
⁸ Division of Epidemiology and Biostatistics, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.

Abstract

Background: Severe COVID-19 has a poor prognosis, and biomarkers may predict disease severity. This study aimed to assess the effect of baseline Vitamin D (VitD) inadequacy on outcome of patients with severe COVID-19 admitted to intensive care unit (ICU) in a tertiary hospital in South Africa.

Methods: Patients with confirmed SARS-CoV-2 were recruited during wave II of the pandemic in Cape Town. Eighty-six patients were included in the study. They were categorized into three groups "VitD deficient, VitD insufficient and VitD sufficient". We combined the VitD deficient with insufficient group to form "VitD inadequate'' group. Cox regression analysis was done to assess the association between VitD status and mortality. Factors with p< 0.05 in adjusted multivariable cox regression were considered statistically significant.

Results: The proportion of VitD inadequacy was 64% (55/86), with significantly higher proportion of hypertension (66%; p 0.012). Kaplan Meir curve showed no significant difference in the probability of survival among the COVID-19 patients admitted in the ICU with or without VitD inadequacy. However, patients with elevated serum creatinine were significantly more at risk of dying (Adjusted Hazard Ratio 1.008 (1.002 - 1.030, p<0.017).

Conclusion: Our study found a high prevalence of VitD inadequacy (combined deficiency and insufficiency) in COVID-19 patients admitted to the ICU. This may indicate a possible risk of severe disease. Whilst there was no statistically significant relationship between VitD status and mortality in this cohort, baseline VitD may be an important prognostic biomarker in COVID-19 patients admitted to the ICU, particularly in those with comorbidities that predispose to VitD deficiency.

Keywords: COVID-19; ICU; Vitamin D; outcomes; prognosis.