Abstract 1411 Prognostic importance of acute infections in patients with pulmonary embolism

Background:

Pulmonary embolism (PE) is associated with high morbidity and mortality, making it a major contributor to global disease burden. Although the prognostic relevance of aggravating conditions such as cancer and chronic heart failure is well established, the importance of acute inflammation and infections on the outcome of patients with acute PE is insufficiently studied.

Methods:

Consecutive PE patients enrolled in a prospective single-centre registry between 09/2008 and 02/2019 were studied. We excluded patients (1) without blood sampling at the time of PE diagnosis, (2) with cardiopulmonary resuscitation (CPR) as the presenting symptom, and (3) with other acute cardiopulmonary or severe infectious disease responsible for clinical presentation and symptoms. We evaluated the impact of inflammatory biomarkers (C-reactive protein [CRP] and procalcitonin [PCT]), antibiotic treatment and clinically apparent infections on adverse in-hospital outcome (treatment with catecholamines, CPR or PE-related death) and in-hospital mortality.

Results:

Data from 749 patients (51.7% female) were analysed. The mean age was 68.0 ± 16.9 years. Overall, 47 (6.3%) patients had an adverse outcome and 27 (3.6%) died during the in-hospital stay. At presentation, 509 patients (68.0%) were classified in the simplified pulmonary embolism severity index (sPESI) high-risk group; associated with an odds ratio (OR) of 5.4 (95% confidence interval [CI] 1.9-15.3) for an adverse in-hospital outcome.

A majority of patients (87.4%) had elevated levels of CRP above the upper limit of normal (5 mg/l) (median 34.8, inter quartile range [IQR] 12.3–74.2 mg/l) and only high levels associated with an adverse in-hospital outcome (Table). In contrast, already a moderate elevation of PCT >0.25 µg/l was associated with a relevantly increased risk and high specificity for an in-hospital adverse outcome (Table).

Antibiotic treatment was initiated in 346 (46.2%) patients within the first 7 days after diagnosis of PE; in the majority of cases due to pneumonia (76.6%). Antibiotic treatment and pneumonia were associated with increased risk of an adverse in-hospital outcome (Table). The impact of acute infections on in-hospital outcomes was comparable to that observed for patients with chronic heart failure (OR 3.3, 95% CI 1.7-6.4 for an adverse in-hospital outcome).

Conclusion:

Acute infections requiring antibiotic treatment or indicated by (moderate) elevation of PCT were associated with a relevantly increased risk of adverse in-hospital outcomes. Our data indicate that acute infections constitute an aggravating condition affecting prognosis in patients with PE requiring consideration in risk stratification.

Parameter	Prevalence	In-hospital adverse outcome	Sensitivity (95% CI)	Specificity (95% CI)	LR+	OR (95% CI)
CRP > 60 mg/l (Youden index optimized cut-off value)	31.1%	10.7%	53.2% (39.2-66.7)	70.4% (66.9-73.6)	1.8	2.70 (1.49-4.90)
CRP > 137 mg/l (cut-off value providing >90% specificity)	10.8%	14.8%	25.5% (15.3-39.5)	90.2% (87.8-92.2)	2.6	3.1 (1.56-6.34)
PCT >0.25 µg/l	9.9% (n=563)	21.4%	33.3% (19.1-51.5)	91.7% (88.9-93.8)	4.0	5.49 (2.57-11.72)
Antibiotic treatment (initiated within 7 days after PE)	46.2%	9.2%	68.1% (53.8-79.6)	55.3 (51.6-58.9)	1.5	2.6 (1.4-5.0)
Pneumonia (diagnosed within 7 days after PE)	35.4%	9.4%	53.2% (39.2-66.7)	65.8% (62.2-69.2)	1.6	2.2 (1.2-4.0)