the prognostic ability of on-admission hemoglobin levels in children with covid-19: the picu experience at a tertiary hospital in iran

Background: covid-19 can lead to hematological abnormalities, including anemia. pre-existing anemia can exacerbate the severity of the disease by increasing the peripheral tissue demand for oxygen. both conditions can contribute to hypoxia. objective: we aimed to investigate the relationship between covid-19 infection and on-admission anemia in critically ill children and assess their effects on severe outcomes. methods: this retrospective study was conducted at children’s medical center during the covid-19 pandemic. patients were divided into two groups based on the first hemoglobin level: anemic and non-anemic. for statistical analysis, we used univariate and multivariate logistic regression models in spss and stata software. results: a total of 133 patients were enrolled with a mean age of 63.2 months. fifty-eight patients had anemia for age, and 75 were non-anemic. among the patients, 53.5% of females and 35.6% of males were anemic (p = 0.04). additionally, 50.5% of anemic patients had significant prehospital comorbidities compared with 20% of previously healthy patients (p = 0.03). overall, 72.9% of patients survived, and 27.1% died. using univariate analysis, death occurred significantly more in anemic patients compared to others (or: 2.27, 95% ci: 1.042 - 4.948, p = 0.037). a logistic regression model was used to adjust the impact of potential confounders, showing that death occurred 1.82 times more often in anemic patients versus non-anemic patients (or: 1.77, 95% ci: 0.79 - 3.98, p = 0.162). furthermore, 54.9% of patients needed vasoactive agents, and 42.7% underwent mechanical ventilation (mv) (p = 0.413 and 0.155, respectively). conclusions: the mortality rate in our study was 27.1%. in the logistic regression model adjusting for comorbidity and sex, we found a small effect relationship between anemia and mortality. however, wide confidence intervals and non-significant p-values indicate the low power of the study, mostly due to the small sample size. further prospective studies with a larger sample size are recommended to determine the exact relationship between anemia and mortality.