However, there were no significant associations between cognitive status and the severity of COVID-19 status experienced by patients previously, which was measured by the length of hospitalization, total oxygen requirement and need of high-flow nasal cannula (HFNC), or severity markers such as lymphocytes, C-reactive protein (CRP), ferritin, or highest recorded d-dimer level, although higher d-dimer correlates with delayed verbal recall and psychomotor speed [8]. Here, CRP is linked to COVID-19.