Assessment of Surrogate Markers/Indices of Systemic Inflammation Among COVID-19 Patients with and Without Comorbid Conditions

Abstract

Background: As widely reported, comorbid conditions are a significant risk for severe COVID-19 infection which is characterized by heightened adverse consequences. Since cytokine-induced inflammatory processes define COVID-19 severity, this study was aimed to evaluate the burden of COVID-19-induced inflammatory episodes, assessed using surrogate markers/indices of inflammation, among COVID-19 patients with and without comorbid conditions in Nigeria. Methods: This was a retrospective analysis of data obtained from treatment-naive real-time polymerase chain reaction (RT-PCR) confirmed COVID-19 patients at the Eleme COVID-19 treatment center in Port Harcourt within the southern region of Nigeria. All relevant data was acquired from case notes, medical review charts, nurses’ charts, and laboratory records by trained research assistants using data acquisition templates. All the data acquired were analyzed and compared between the COVID-19 patients with and without comorbid conditions using standard descriptive and comparative statistical tools. Results: Among those studied (n=604), 31.8% (n=192) had at least one pre-existing comorbid condition while 68.2% (n=412) had no comorbid conditions before COVID-19 diagnosis/subsequent presentation. The comorbid positive subgroup were mostly males and had higher mean age, BMI, body temperature, SBP, DBP, and higher proportions of elderly patients, high-risk occupational status (health workers) and social behavior (cigarette smoking), obesity, severe disease, and worse disease outcome, but lower oxygen saturation compared to the comorbid negative subjects at presentation. Additionally, the comorbid positive subjects also had higher mean levels of blood urea, creatinine, pro-calcitonin, CRP, ferritin, Glasgow prognostic scores, fibrinogen, D-Dimer, and the fibrinogen-albumin ratio, total white cell counts, isolated neutrophil counts, neutrophil-lymphocyte count ratio, and the platelet-lymphocyte count ratio but lower levels of potassium, albumin, isolated lymphocyte count and isolated platelet count compared to the comorbid negative subjects (p<0.05). The inflammatory markers/indices were significantly associated with obesity, age ≥65 years, hypertension, past/current cigarette smoking, diabetes, and cardiovascular disease. Conclusion: Comorbidities are significantly associated with amplified systemic inflammatory markers and indices among COVID-19 subjects. This may indicate the pathophysiologic link between various comorbidities and the COVID-19 severity among Nigerians. However, further studies are recommended to substantiate the findings of the current study.