Association of the Cumulative Inflammatory Index and Long-Term Mortality in Stroke-Associated Pneumonia

Stroke-associated pneumonia (SAP) represents a common complication that increases the mortality risk in individuals who have experienced a stroke. We aimed to explore the relationship between the cumulative inflammatory index (IIC) and long-term mortality in patients with SAP.

This study sourced participants with SAP from the Nanjing Stroke Registry Program. The IIC was computed using the formula: (mean corpuscular volume × red cell distribution width × neutrophils) divided by (lymphocytes × 1000). To gauge the diagnostic utility of inflammatory markers, time-dependent receiver operating characteristic curves were plotted. Furthermore, to elucidate the connection between IIC and long-term mortality, survival analysis was conducted via Cox proportional hazard regression models.

The analysis enrolled a total of 557 SAP patients, with a median age of 66 years and 391 males accounting for 70.2% of the cohort. The predictive accuracy of the IIC for mortality was 0.697 (95% confidence interval [CI]: 0.637-0.757). In Cox proportional hazard regression models, the IIC was significantly related to mortality (continuous: hazard ratio [HR]: 1.04; 95% CI: 1.02-1.06; P <0.001; tertile 3 versus tertile 1: HR: 3.03; 95% CI: 1.75-5.25; P <0.001). Restricted cubic spline analysis demonstrated a progressively escalating association between IIC and mortality among SAP patients, with statistical significance (P = 0.003).

This research revealed that elevated IIC levels were linked to a heightened long-term mortality risk among individuals with SAP. IIC may emerge as a feasible and robust biomarker for mortality prediction in SAP patients.