Correlation of Lactate Dehydrogenase Level with Severity of Disease and In-hospital Outcome in Individuals Diagnosed with COVID-19: A Retrospective Study

Introduction: The presence of tissue damage in the lungs, kidneys, heart, or other organs can be detected by monitoring the level of Lactate Dehydrogenase (LDH) in the blood and considered a reliable biomarker in early prediction of patients' prognosis. Aim: To determine extent of correlation between LDH level with the spectrum and in-hospital outcome of Coronavirus Disease -2019 (COVID-19) infected patients. Materials and Methods: This retrospective research was undertaken during March 2020 to May 2020, based on the data of 205 COVID-19 infected patients, reported at Dammam Medical Complex, Dammam, Eastern Province, Saudi Arabia. Patients' records were retrieved and the following data were recorded-age, gender, nationality, co-morbidities, lactate dehydrogenase level, number of days since the patient tested positive (Up to 7,14 and > 14 days), COVID-19 symptoms [mild, moderate, or severe as per British Thoracic Society guidelines (CURB (Confusion, Blood Urea Nitrogen, Respiratory Rate, Blood Pressure)-65)]. The data was collected and tabulated as mean +/- SD, frequency and percentages. Analysis was carried out using specialized software of Statistical Package for Social Sciences (SPSS) version 20.0. Results: On analysis of the collected data of all 205 included patients, the LDH level was found significantly high among males, 46-60 years old, and among non-Saudi patients. The severity of COVID-19 symptoms and LDH levels were found to have a strong relationship (p-value < 0.001). Patients between the ages of 46 and 60 were more likely (4.3 times) to have poor outcomes, and diabetes mellitus was predicted to be 2.32 times more likely to be associated with poor COVID-19 outcomes. Raised LDH levels were > 5 times more likely to lead to in-hospital poor outcomes compared to those with borderline LDH levels. Conclusion: LDH level is a reliable predictor for the cause of COVID-19. The results of the present study suggest that patients aged 46-60 years, diabetic patients, or those suffering from severe symptoms of COVID-19 have raised levels of LDH.