Pulmonary artery diameter predicts mortality in community-acquired pneumonia.

BACKGROUND

The impact of pneumonia on pulmonary hemodynamics may be underestimated by available risk scores, such as CURB-65 and the Pneumonia Severity Index (PSI). We evaluated the prognostic utility of pulmonary artery diameter (PAD) in pneumonia.

METHODS

We retrospectively screened 1,887 CT pulmonary angiography scans. Pneumonia was defined as a pulmonary infiltrate accompanied by clinical or laboratory evidence of infection. Patients' characteristics and outcomes were extracted from medical records. PAD was measured using three methods (PAD1-3) and tested for association with mortality.

RESULTS

A total of 243 pneumonia cases were included. PAD1-3 showed strong inter-method agreement (ICC = 0.88, P < 0.0001). PAD1 showed the most consistent association with mortality and was widely applicable. PAD1 was larger in non-survivors at 30 days (29.6 versus 26.4 mm, P = 0.0003), 90 days (28.5 versus 26.4 mm, P = 0.002), and one year (28.0 versus 26.4 mm, P = 0.01). Thirty-day mortality increased stepwise across PAD1 tertiles (3.8%, 13.9%, and 22.8%, P = 0.001), as did 90-day and one-year mortality. PAD1 was an independent predictor of 30-day mortality (HR 1.11 per mm, 95% CI 1.02-1.22, P = 0.02). PAD1, CURB-65, and PSI showed comparable performance in predicting 30-day mortality (ROC-AUC = 0.70-0.73).

CONCLUSIONS

PAD is independently associated with mortality in pneumonia and demonstrates comparable predictive performance to CURB-65 and PSI for 30-day mortality. These findings support incorporating vascular imaging markers into risk stratification scores.