C-reactive protein elevation is associated with increased morbidity and mortality in elderly burned patients

C-reactive protein (CRP) is an acute-phase protein produced in response to inflammation after traumatic injury. We posit that C-reactive protein (CRP) is reliable in predicting morbidity and mortality following severe burn. In this study, we explored the relationship between serum CRP values and clinical outcomes in the severely burned.

Using the Research Network within the TriNetX database, we queried de-identified burn patient data across the United States and enrolled 36,556 burn patients with reported CRP values from 2006 to 2020.

Circulating CRP levels were elevated significantly in patients ≥60 years as well as in males and African Americans (p < 0.05). CRP levels reached the zenith on the first day after burn, and were highest when burn size reached 60% total body surface area (TBSA). After bisecting the data at 10 mg/L of CRP, we compared clinical findings between patient groups (n = 16,284/18,647 in high/low CRP levels). The risk of patient death doubled in the high CRP group from 4.687% to 9.313%, with higher incidences of sepsis, skin infection, and myocardial infarction (p < 0.05). Moreover, mortality increased from 0.9% to 1.926% in those younger than 20 years when comparing the low and high CRP groups, whereas mortality significantly increased from 8.84% to 15.818% in those ≥60 years old (p < 0.05). Both elderly and paediatric groups had significant increases in the diagnosis of sepsis-associated with increased CRP expression. However, incidences of skin infection, pneumonia, and acute kidney injury increased significantly only in the elderly group (p < 0.05).

Elevated CRP expression is common in burn patients. The factor of age influenced the association of CRP expression to clinical outcomes.