Prediction of COPD by the single-breath nitrogen test and various respiratory symptoms.
ERJ Open Res
; 7(3)2021 Jul.
Article
em En
| MEDLINE
| ID: mdl-34589539
ABSTRACT
Early identification of subjects running an increased risk of contracting COPD enables focus on individual preventive measures. The slope of the alveolar plateau of the single-breath nitrogen washout test (N2-slope) is a sensitive measure of small-airway dysfunction. However, its role remains unexplored in predicting hospital admission or death related to COPD, i.e. incident COPD events, in relation to the presence of various respiratory symptoms. A random population sample of 625 men, aged 50 (n=218) or 60â
years (n=407), was followed for 38â
years for incident COPD events. At baseline, a questionnaire on respiratory symptoms and smoking habits was collected, spirometry and the single-breath nitrogen test were performed, and the N2-slope was determined. Proportional hazard regression (Cox regression) analysis was used for the prediction model. The N2-slope improved the prediction of COPD events significantly beyond that of respiratory symptoms weighted all together and other covariates (hazard ratio 1.63, 95% CI 1.20-2.22; p<0.005), a prediction applicable to subjects without (p=0.001) and with (p<0.05) airway obstruction. Dyspnoea and wheezing were the most predictive symptoms. The combination of the N2-slope and number of respiratory symptoms notably resulted in an effective prediction of incident COPD events even in nonobstructive subjects, as evidenced by a predicted incidence of â¼70% and â¼90% for a very steep N2-slope combined with many respiratory symptoms in subject without and with airway obstruction, respectively. The alveolar N2-slope should be considered in the critical need for further research on early diagnosis of COPD.
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
/
Risk_factors_studies
/
Screening_studies
Idioma:
En
Revista:
ERJ Open Res
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Suécia