Serum zinc levels in pediatric patients with COVID-19

Abstract

Zinc has potent immunoregulatory and antiviral effects that are critical for growth, immunity, and neurologic development. The aim of this study was to determine the clinical significance of serum zinc levels in pediatric patients with COVID-19 and to demonstrate its association with disease severity. This prospective observational study was conducted between August 3 and November 15, 2020, in pediatric patients aged 1 month to 18 years with confirmed COVID-19 using reverse transcription-polymerase chain reaction. We defined a control group whose serum zinc levels were determined 1 year ago at the same time as those of patients with COVID-19. We used 70 μg/dL as the cut-off zinc value to define zinc deficiency. Statistical analyses were performed using the SPSS for Windows statistics package program. One hundred children with confirmed COVID-19 and 269 children in the control group participated in the study. The median age was 13.3 (IQR: 8–15.4) years in patients with confirmed COVID-19, 11 patients had low serum zinc levels, and 89 patients had normal serum zinc levels. Patients in the group with low zinc levels had a significantly higher hospitalization rate than the group with normal zinc levels (5 (45.5%) and 10 patients (11.2%), respectively) ( p = 0.011). The median serum zinc level in patients with COVID-19 was 88.5 mcg/dL (IQR 77.2–100), which was significantly lower than the median level in the control group, which was 98 mcg/dL (IQR 84–111) ( p = 0.001). There was no association between the severity of COVID-19 and the serum zinc levels of the children. Conclusion : Serum zinc levels may be influenced by many factors such as fasting status, diurnal variation, exercise, and sex, and may give an impression of the zinc status of the population rather than reflecting the individual. The fact that the incidence of hospitalization was significantly higher in patients with both COVID-19 and low serum zinc levels suggests that these patients require a detailed assessment of their living environment. What is Known: • Serum zinc levels have been found to be low in adult patients diagnosed with COVID-19. • There was a correlation between the severity of COVID-19 and serum zinc levels in adults. What is New: • Children with low serum zinc levels were found to have a higher number of hospitalizations. • No association was found between the severity of COVID-19 disease and serum zinc levels in children.

Free Zinc as a Predictive Marker for COVID-19 Mortality Risk

“…In previous studies, COVID-19 was characterized by a marked decrease in total serum zinc, and clinical data so far indicate that the individual zinc status affects susceptibility, severity, and mortality related to the infection [ 13 , 14 , 15 , 16 , 17 , 20 , 21 ]. The current study adds novel and relevant information on zinc status, and demonstrates that COVID-19 is also associated with a severe decrease in the readily available free zinc pool in serum.…”

“…Regarding its role in SARS-CoV-2, zinc was found to not only improve the antiviral immune response, but also (i) prevent interaction of SARS-CoV-2 with the angiotensin-converting enzyme 2 (ACE2) on the cell membrane, (ii) affect cellular expression of ACE2, and (iii) impair viral replication (reviewed in [ 9 , 12 ]). Observational studies mostly comparing total serum zinc in mild, moderate, and/or severe COVID-19 patients provided strong indications that disease severity is associated with very low serum zinc levels [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ].…”

The Association Between Antioxidants and COVID-19 Outcomes: a Systematic Review on Observational Studies

“…Out of 38 studies, 22 of them were cohort, 5 of them used case–control design, and 11 were cross-sectional. Investigations were conducted in different countries: 9 studies were conducted in Iran [ 3 , 4 , 6 , 9 , 15 , 18 – 21 ], while the remaining were performed in Turkey [ 22 – 26 ], China [ 7 , 10 , 27 , 28 ], Spain [ 14 , 29 , 30 ], Saudi Arabia [ 1 , 5 , 31 ], France [ 12 , 32 ], Belgium [ 33 ], Korea [ 34 ], Nigeria [ 8 ], India [ 35 , 36 ] Brazil [ 2 ], and Japan [ 37 ]. Twenty-one studies just analyzed the association between Zn and COVID-19 outcomes [ 2 , 4 , 5 , 9 , 12 , 13 , 15 , 18 – 20 , 22 , 26 , 29 , 30 , 32 , 33 , 35 – 38 ], three studies analyzed the association between Se and COVID-19 outcomes [ 8 , 39 ], one analyzed the association between vitamin A and COVID-19 outcomes [ 40 ], eight studies analyzed the association between vitamin C and COVID-19 outcomes [ 1 , 7 , 10 , 23 – 25 , 27 , 28 ], and eight studies investigated the association between mixed antioxidant vitamins, Se, and Zn with COVID-19 [ 3 , 8 , 9 , 14 …”

“…Another case–control study in Iran [ 19 ] indicated that the median of Zn levels in the cases was lower than the controls (median; IQR 56 ng/ml; 23 vs. 110 ng/ml; 27; respectively) ( P < 0.01). Another case–control study in Turkey [ 22 ] found that serum Zn level was significantly lower among COVID-19 patients (median serum Zn level, 88.5; IQR, 77.2–100 µg/d) compared to the control group (median serum Zn level, 98; IQR, 84–111 µg/dl). Another case–control study in Iran [ 20 ] found that 52% of patients had Zn deficiency, and serum Zn levels of patients were lower than the healthy individuals (67.61 ± 15.10 µg/dl vs. 86.66 ± 11.76 µg/dl; P < 0.001).…”

“…The findings demonstrated that there was no variation in CRP between groups (median; IQR 104.95 mg/l; 51.1–158.69 vs. 108.13 mg/l; 53–157.11; P = 0.958). Also, another case–control study [ 22 ] was conducted in Turkey. The findings demonstrated that serum Zn levels and CRP did not correlate (median; IQR, 2.6 mg/l; 0.80–8.80 vs. 2.2 mg/l; 0.80–5.50; P = 1.000).…”