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Vitamin D Levels Are Reduced at the Time of Hospital Admission in Sicilian SARS-CoV-2-Positive Patients.

Take Home Message

In this cross-sectional retrospective study, the vitamin D status at the time of hospital admission was evaluated in 50 COVID-19 positive patients in Sicily, Italy and was compared to 100 people that did not have COVID-19 but were the same age and gender. Markedly low levels of serum vitamin D were found in COVID-19 patients, but vitamin D levels did not seem to be associated with inflammation markers or clinical severity. Although serum vitamin D levels were low at the time of hospital admission in Sicilian SARS-CoV-2-positive patients, it is not clear whether low vitamin D status has an impact on the how severe or the outcome of COVID-19 patients.

Purpose

This cross-sectional retrospective study evaluated the vitamin D status at the time of hospital admission of 50 COVID-19 patients who were consecutively admitted to the Infectious Diseases Unit of San Marco Hospital in Catania, Italy from March to July 2020 and compared them with 100 control subjects matched for age and sex.

Results

  • Median serum levels of 25(OH)D were significantly lower [(12.5 (31.3 nmol/l) vs. 20.5 ng/mL (51.3 nmol/l)] in COVID-19 patients than in controls.
  • In particular, 23 COVID-19 patients had values of <12 ng/mL (<30 nmol/l), 11 COVID-19 patients had values of 12–20 ng/mL (30-50 nmol/l), and only 16 COVID-19 patients had values ³20 ng/mL (50 nmol/l).
  • The number of subjects with 25(OH)D values of <12 ng/mL (<30 nmol/l) was significantly higher in COVID-19 patients than in controls.
  • There were no significant differences in 25(OH)D values as a function of ventilatory support.
  • No correlation was observed in COVID-19 patients between 25(OH)D values and the length of hospitalization or levels of IL-6, D-dimer or CRP, whereas 25(OH)D serum levels correlated positively with calcium corrected for albumin and phosphorus and negatively correlated with PTH and age.

Who

Fifty hospitalized COVID-19 positive patients (26 men, 52%; 24 women, 48%) were enrolled in this study in Catania, Italy. The median age was 65 years, ranging from 24-98 years. One-hundred hospitalized COVID-19 negative patients (44 men, 44%; 66 women, 66%) served as controls. The median age of the control group was 61 years, ranging from 22-89 years.

Things to Keep in Mind

  • The cross-sectional and retrospective design limits the study’s ability to establish the causality and temporality of the associations.
  • The study population is small, limiting the ability to generalize the findings to other clinical settings. More patients are needed to conclude with enough power from subgroup analyses and to evaluate the impact of vitamin D values on mortality.
  • Due to limited information on comorbidities for patients and controls, the low 25(OH)D levels observed may solely reflect worse overall health status.

Author’s Conclusions

In conclusion, this retrospective study shows markedly low levels of vitamin D in patients with positive PCR for SARS-CoV-2, but it does not support a causal role of vitamin D deficiency either in infection by SARS-CoV-2 or in the clinical course of COVID-19. Other studies with a larger population and a longitudinal design are necessary to understand the real role of vitamin D in the development of COVID-19.

Study Design

  • This cross-sectional retrospective study evaluated the vitamin D status at the time of hospital admission of 50 COVID-19 patients who were consecutively admitted to the Infectious Diseases Unit of San Marco Hospital in Catania, Italy from March to July 2020 and compared them with 100 control subjects matched for age and sex.
  • COVID-19 diagnosis was confirmed by SARS-CoV-2 polymerase chain reaction.
  • The clinical history of every patient was evaluated, including laboratory exams, outcome, length of hospitalization, and type of oxygen therapy or ventilation needed during hospitalization [none, nasal cannula/Venturi mask/high-flow nasal cannula (HFNC), continuous positive airway pressure (cPAP)/non-invasive ventilation (NIV) or invasive ventilation].
  • Controls were the first 100 SARS-CoV-2-negative patients matched for age and sex, who were consecutively admitted in the same period to the Unit of Internal Medicine, University Policlinic in Catania, Italy. None of the patients or controls were taking vitamin D supplements at the time of the evaluation or in the previous 3 months.
  • Body mass index (BMI) was calculated for all subjects.
  • The following biochemical parameters were measured: calcium, phosphorus, creatinine, alkaline phosphatase (ALP), 25-OH vitamin D2 (25(OH)D), parathyroid hormone (PTH), interleukin-6 (IL-6), D-dimer, and C-reactive protein (CRP).
  • According to the Institute of Medicine, vitamin D deficiency is defined as a serum 25(OH)D level of <12 ng/mL (30 nmol/l) and insufficiency as a 25(OH)D level of 12–20 ng/mL (50 nmol/l). A 25(OH)D level of >20 ng/mL (50 nmol/l) was accepted as adequate.

Reference

Gaudio A, Murabito AR, Agodi A, Montineri A, Castellino P, D O CoV Research. Vitamin D Levels Are Reduced at the Time of Hospital Admission in Sicilian SARS-CoV-2-Positive Patients. Int J Environ Res Public Health. 2021 Mar 27;18(7):3491. doi: 10.3390/ijerph18073491. PMID: 33801759; PMCID: PMC8036292.

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2021-12-09T11:50:26-05:00