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

Abstract

Background: Because of the lack of sufficient data, we aimed to investigate the role of serum 25(OH) vitamin D level on COVID severity and related mortality. Methods: This was a retrospective observational study. Data, including sociodemographic features, clinical characteristics, and laboratory data, and 25(OH) vitamin D levels were recorded for each study participant. Patients were stratified into different vitamin D groups; Normal (Serum 25(OH) vitamin D level >30 ng/mL), Vitamin D insufficiency (21-29 ng/mL), and deficiency (<20 ng/ mL). The severity of COVID was classified according to the Chinese Clinical Guideline for classification of COVID-19 severity. Mortality data were determined for participants. Univariate and multivariate Logistic regression analysis was performed to determine independent predictors of in-hospital mortality. Results: Overall, 149 COVID-19 patients (females 45.6%, mean age 63.5 ± 15.3 (range 24-90 years) years) were included. Fortyseven patients (31.5%) had moderate COVID-19, whereas 102 patients (68.5%) had severe-critical COVID-19. The mean 25(OH) vitamin D level was 15.2 ± 10.3 ng/mL. Thirty-four (22.8%) and 103 (69.1%) patients had vitamin D insufficiency and deficiency, respectively. Mean serum 25(OH) vitamin D level was significantly lower in patients with severe-critical COVID-19 compared with moderate COVID-19 (10.1 ± 6.2 vs. 26.3 ± 8.4 ng/mL, respectively, p<0.001). Vitamin D insufficiency was present in 93.1% of the patients with severe-critical COVID-19. Multivariate logistic regression analysis revealed that only lymphocyte count, white blood cell count, serum albumin and, 25(OH) vitamin D level were independent predictors of mortality. Conclusion: Serum 25(OH) vitamin D was independently associated with mortality in COVID-19 patients.

Association of Vitamin D Status with SARS-CoV-2 Infection or COVID-19 Severity: A Systematic Review and Meta-analysis

“…In contrast, D-dimer concentrations were moderately associated with 25(OH)D concentrations ( r = 0.437, P < 0.05) ( 61 ). Karahan and Katkat ( 54 ) in their retrospective study in 149 COVID-19 patients found a significant negative relation between serum 25(OH)D concentration and CRP ( r = −0.253, P = 0.002). Kerget et al ( 50 ) found a significant negative correlation only with CRP ( r = −0.297, P = 0.01), but not IL-6, ferritin, and D-dimer.…”

“…Among 15 studies that assessed the relation between mortality and VDD, 13 studies were included in the analysis. Pooled analysis of 4 adjusted studies that used the Cox survival method ( 13 , 51 , 56 , 60 ) (HR: 2.35; 95% CI: 1.22, 4.52; I 2 : 84%; Figure 4 A ) and 5 studies ( 44 , 47 , 53 , 55 , 62 ) with crude OR (OR: 2.62; 95% CI: 1.13, 6.05; I 2 : 47.8%; Figure 4B ) indicated a significant association of VDD with mortality, while in adjusted studies that used logistic regression ( 54 , 59 , 65 ), no relation was observed (OR: 1.05; 95% CI: 0.63, 1.75; I 2 : 76.6%). Two studies were not included in the analysis since 1 study had an RCT design ( 36 ) and another one used different statistical methods ( 64 ).…”

“…Moreover, 6 studies compared serum concentrations of 25(OH)D between deceased patients and those who survived ( 50 , 54 , 55 , 60 , 63 , 66 ); pooled analysis of studies indicated lower concentrations of 25(OH)D in patients who died compared with those who survived (WMD: −9.05 ng/mL; 95% CI: −13.86, −4.23; I 2 : 87.8%; Supplemental Figure 3 ). Results of studies are summarized in Supplemental Table 10 .…”

“…In 2 studies peak CRP and CRP >40 mg/L were evaluated in related to VDD ( 38 , 47 ). In 1 study, only IL-6 was measured, and in the other 2 studies, the relation was examined using Pearson correlation coefficients ( 50 , 54 ). Four studies failed to detect a significant relation ( 14 , 44 , 64 , 61 ); among them, the highest-quality study was a clinical trial that failed to discern the effect of cholecalciferol supplementation on CRP and D-dimer ( 14 ), although it does not appear that 25(OH)D concentration is correlated with inflammation in nonacute phases, given that the evidence is currently not sufficient.…”

Vitamin D deficiency is associated with COVID‐19 positivity and severity of the disease

“…Besides this, it has crucial regulatory roles in the adaptive and innate immune systems 4 . It was shown that vitamin D deficiency is quite common among COVID‐19 patients 5 . A recent clinical study showed that COVID‐19 patients supplemented with vitamin D had less severe symptoms of the disease 6 …”