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Background and purpose: There are controversies on the association between electrolytes and Coronavirus disease 2019 (COVID-19) and its severity. Studies on these issues may help in resolving ambiguities. The purpose of this study was to assess the association between electrolyte indices and being infected with COVID-19 and developing severe symptoms using a meta-analysis.
Materials and methods: A thorough search was done in national and international electronic databases using Medical Subject Headings (MeSH) terms. Quality assessment was conducted by Newcastle-Ottawa scale (NOS) checklist. We estimated the standardized mean difference between electrolyte indices and the incident of COVID-19 infection and its severity.
Results: After screening the papers, 12 met the inclusion criteria. According to the meta-analysis results, the standardized mean differences for serum level of sodium and potassium between the dead and survived COVID-19 patients was estimated to be 0.22 (95% CI: -0.03, 0.46) and 0.14 (95% CI: -0.22, 0.50), respectively. The standardized mean differences for serum levels of sodium, calcium, and potassium between patients with severe and non-severe COVID-19 were estimated to be -0.28 (95% CI: -0.72, 0.17), -1.07(95% CI: -1.58, -0.55), and -0.10 (95% CI: -0.47, 0.27), respectively.
Conclusion: In this meta-analysis, the standardized mean difference for calcium was significantly lower in severe COVID-19 patients compared to that in patients with mild and moderate forms of the disease.