RT Journal Article
SR Electronic
T1 Long-term reproducibility of exhaled nitric oxide and exhaled breath temperature in healthy children
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P1088
VO 42
IS Suppl 57
A1 Francesca Ruggeri
A1 Mario Barreto
A1 Lorenza Chiossi
A1 Carlotta Bianchini
A1 Ilaria Caiazzo
A1 Maria Chiara Supino
A1 Susy Martella
A1 Maria Pia Villa
YR 2013
UL http://erj.ersjournals.com/content/42/Suppl_57/P1088.abstract
AB BackgroundMeasurements of the fractional concentration of exhaled nitric oxide (FENO) and exhaled breath temperature (EBT) are easy to perform, non-invasive and considered reproducible at short-term; data on their long term reproducibility is needed.AimsTo assess reproducibility of FENO and EBT in healthy children one-year apart and their relationship with lung function and anthropometric changes.MethodsIn 41 healthy children (24 males) aged 9.8±1.6 yr, range 8.0-13.8, we obtained duplicated measurements of FENO and EBT in two sessions one-year apart (2011 and 2012). Subjects did also spirometry in both sessions. The intraclass coefficient correlation (ICC) and the coefficient of repeatability (CR=2 SD) were assessed. Overtime changes in variables (“D” prefix) were calculated.ResultsIntra-session reproducibility of duplicate measurements was high in both sessions [(ICC >0.94 for both FENO and EBT); (CR: FENO 5.2 ppb and 3.0 ppb, EBT 1.8 and 1.2 °C)]. Geometric means (95% confidence interval) did not change significantly from the 2011 to the 2012 sessions [FENO: 10.6 (9.3-12.2) ppb and 10.2 (9.2-11.3) ppb; EBT: 32 (31.3-32.7) °C and 32.6 (31.9-33.2) °C]. Reproducibility decreased after 1 year [FENO (ICC: 0.48, CR: 11.0 ppb); EBT (ICC: 0.75, CR: 3.5 °C)]. The between-year percent increase in FENO correlated with decreased lung function (DFEV1% r=-0.33, DFEF25-75 % r=-0.39, p<0.05) whereas EBT increased with BMI (DBMI 0.41, p=0.008).ConclusionReproducibility of both FENO and EBT decreases after one year in healthy children; their changes have a different meaning; FENO is more affected by changes in bronchial patency whereas EBT by increases in body mass index.