Relationship between serum lactate dehydrogenase levels and prognosis in patients infected with omicron and delta variants of COVID-19: A cross-sectional study.

Determining the prognosis of COVID-19 is crucial for understanding disease trends and developing effective treatment strategies, particularly for severe cases. However, there is currently insufficient evidence regarding the role of lactate dehydrogenase (LDH) in COVID-19 and its prognostic implications. This retrospective cross-sectional study analyzed data from all patients hospitalized at Urmia Imam Khomeini Hospital between September 2021 and March 2023 with a diagnosis of COVID-19 involving the Delta and Omicron variants. Patient information, including age, sex, duration of hospitalization, admission to the intensive care unit (ICU), strain type, and outcomes, was extracted. Exclusion criteria encompassed myocardial infarction, lung, liver, blood, skeletal muscle diseases, injury, neoplasm, pancreatitis, pregnancy, poisoning, unwillingness to participate in the study, and the use of ascorbic acid. A total of 609 patients with an average age of 54.80 years were included in this study. Among these patients, 56.3% were female, and the mortality rate was 20.7%. The serum LDH levels were significantly higher in patients who succumbed to the disease (P < 0.001), those requiring ICU admission (P < 0.001), and female patients (P = 0.02) compared to other groups. Furthermore, the LDH serum levels exhibited a strong significant correlation with the duration of hospitalization (r = -0.11, P = 0.007). The results revealed that there is a difference in the mean serum LDH levels between deceased patients and discharged patients (P < 0.001). The findings indicate that elevated serum LDH levels are associated with increased mortality, prolonged hospitalization, ICU admission, and infection with the Delta variant of COVID-19.