Understanding COVID-19-related Acute Renal Injury in Elderly Individuals: Preexisting Systemic Inflammation before COVID-19 (SIC).

In this study, we examined preexisting systemic inflammation before COVID-19 (SIC), as assessed through C-reactive protein (CRP) levels, to gain insights into the origins of acute kidney injury (AKI) in adults with comorbidities affected by COVID-19. Although aging is not categorized as a disease, it is characterized by chronic inflammation, and older individuals typically exhibit higher circulating levels of inflammatory molecules, particularly CRP, compared to younger individuals. Conversely, elevated CRP concentrations in older adults have been linked with the development of comorbidities. Simultaneously, these comorbidities contribute to the production of inflammatory molecules, including CRP. Consequently, older adults with comorbidities have higher CRP concentrations than their counterparts without comorbidities or those with fewer comorbidities. Given that CRP levels are correlated with the development and severity of AKI in non-COVID-19 patients, we hypothesized that individuals with greater SIC are more likely to develop AKI during SARS-CoV-2 infection than those with less SIC.