C-Reactive Protein - A Promising Marker for Patients with Ischemic Heart Disease along with Covid-19 among South Indian Population

BACKGROUND New corona virus respiratory syndrome is a health emergency due to high infectivity and high case fatality in patients with comorbid conditions like ischemic heart disease. The diagnostic methods of corona virus disease (Covid-19) are still in experimental stage. Hence, a sensitive and specific disease progression marker of Covid-19 is needed. CRP (C-reactive protein) is synthesised by liver. It is elevated in infection and inflammatory conditions as it is an acute phase protein. The purpose of this study was to evaluate CRP as a promising marker for predicting severity of Covid-19 in ischemic heart disease patients and to correlate the impact of CRP with other circulating cardiac biomarkers in different age groups and both sexes. METHODS This is a cross sectional study done among south Indian population mostly from Tamil Nadu and Andhra Pradesh. 232 cases were selected and divided into two groups based on age, sex and confirmed Covid-19 positive cases by RT-PCR (Reverse transcription-polymerase chain reaction), admitted and treated in Rajiv Gandhi Government General Hospital, Chennai. RESULTS In this study, CRP levels were elevated in the age group of 50 - 70 years (66.96 ± 70.09 mg/dL) than CRP levels of age group 30 - 50 years (82.31 ± 90.23 mg/dL) and P value was found to be significant in the age group of 50 - 70 years. Lactate dehydrogenase (LDH) levels were elevated in the age group of 30 - 50 years (380.77 ± 252.23 U/L) than the LDH levels of age group 50 - 70 years (393.53 ± 206.83 U/L) and P value was found to be significant in the age group of 30 - 50 years. Aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatine kinase (CK) levels are the additional cardiac enzymes found to be elevated in this study. CRP showed a positive correlation with LDH (r = 0.221 P < 0.001) in both males (r = 0.06 and P < 0.001) and females (r = 0.45 and P < 0.001) with a significant P value. Receiver operating characteristics (ROC) curves for CRP Vs age group shows a sensitivity of 91.15 % and specificity of 92.52 % and area under curve of 0.556. CONCLUSIONS CRP can be used as a promising marker for early detection and timely intervention of ischemic heart disease in Covid-19 patients especially in the age group of 50 - 70 years and thereby reduces the mortality. KEYWORDS Biomarkers, Heart Disease, Mortality, Prognosis