Breath-print analysis by e-nose may refine risk stratification for adverse outcomes in cirrhotic patients

Background & Aims: The spectrum of volatile organic compounds in the exhaledbreath (breath-print,BP) has been shown to characterize patients with cirrhosis andwith worse hepatic function. However, the association of different BPs with clinicallyrelevant outcomes has not been described yet. Hence, we aimed to evaluate the associationbetween BPs, mortality and hospitalization in cirrhotic patients and to compareit with that of the “classical” prognostic indices (Child-PughClassification [CPC]and MELD).Methods: Eighty-ninecirrhotic patients (M/F 59/30, mean age 64.8 ± 11.3, CPCA/B/C 37/33/19) were recruited and followed up for a median time of 23 months.Clinical and biochemical data were collected. Breath collection and analysis were obtainedthrough Pneumopipe® and BIONOTE e-noserespectively.Results: Four different BP clusters (A, B, C, D) were identified. BP clusters A and Dwere associated with a significantly increased risk of mortality (HR 2.9, 95% confidenceintervals [CI] 1.5–5.6) and hospitalization (HR 2.6, 95% CI 1.4–4.6), even inmultiple adjusted models including CPC and MELD score (adjusted [a]HR 2.8, 95% CI1.1–7.0 for mortality and aHR 2.2, 95% CI 1.1–4.2 for hospitalization). CPC C maintainedthe strongest association with both mortality (aHR 17.6, 95% CI 1.8–174.0) andhospitalization (aHR 12.4, 95% CI 2.0–75.8).Conclusions: This pilot study demonstrates that BP clusters are associated with significantclinical endpoints (mortality and hospitalization) even independently from “classical”prognostic indices. Even though further studies are warranted on this topic, ourfindings suggest that the e-nosemay become an adjunctive aid to stratify the risk ofadverse outcomes in cirrhotic patients