C-reactive protein levels and post-ICU mortality in nonsurgical intensive care patients.

Background: There are no data on the association between acute inflammation during critical illness and long-term mortality in ICU patients.
Methods: Nonsurgical patients with an ICU length of stay > 24 h surviving until ICU discharge were included into this prospective, observational, follow-up study. Demographics, chronic diseases, admission diagnosis, the Simplified Acute Physiology Score (SAPS) II, length of ICU stay, maximum C-reactive protein (CRP) levels during the ICU stay (CRPmax), and CRP levels at ICU discharge (CRPdis) were documented. After a follow-up time of 1.88 ± 1.16 years (range, 0.5-4 years), the survival status was determined.
Results: Seven hundred sixty-five patients were enrolled into the study protocol. One hundred fifty-eight patients (20.7%) died within 0.62 ± 0.88 years after ICU discharge. Cumulative survival rates differed between patients grouped into the CRPmax and CRPdis quartiles. Patients in the first and second CRPmax quartiles had better cumulative survival rates than those in higher CRPmax quartiles (all P < .001). Patients in the first CRPdis quartile had better cumulative survival rates than those in higher CRPdis quartiles (all P < .001). Using adjusted Cox proportional hazards models, both CRPmax and CRPdis were independently associated with post-ICU mortality (both P < .001). Furthermore, the number of chronic diseases (P < .001), age (P < .001), and the SAPS II (P = .03) were associated with post-ICU mortality in both Cox models.
Conclusions: CRP levels during critical illness seem independently associated with post-ICU survival in nonsurgical ICU patients. Future research focusing on the association between acute systemic inflammation and post-ICU outcome is warranted in order to improve long-term survival of critically ill patients.