The clinical utility of long-term humidification therapy in chronic airway disease

Summary 

Aim

Persistent airway inflammation with mucus retention in patients with chronic airway disorders such as COPD and bronchiectasis may lead to frequent exacerbations, reduced lung function and poor quality of life. This study investigates if long-term humidification therapy with high flow fully humidified air at 37 °C through nasal cannulae can improve these clinical outcomes in this group of patients.

Method

108 patients diagnosed with COPD or bronchiectasis were randomised to daily humidification therapy or usual care for 12 months over which exacerbations were recorded. Lung function, quality of life, exercise capacity, and measures of airway inflammation were also recorded at baseline, 3 and 12 months.

Results

Patients on long-term humidification therapy had significantly fewer exacerbation days (18.2 versus 33.5 days; p = 0.045), increased time to first exacerbation (median 52 versus 27 days; p = 0.0495) and reduced exacerbation frequency (2.97/patient/year versus 3.63/patient/year; p = 0.067) compared with usual care. Quality of life scores and lung function improved significantly with humidification therapy compared with usual care at 3 and 12 months.

Conclusion

Long-term humidification therapy significantly reduced exacerbation days, increased time to first exacerbation, improved lung function and quality of life in patients with COPD and bronchiectasis.

Clinical trial registered with www.actr.org.au; Number ACTRN2605000623695

Keywords: Bronchiectasis, COPD, Humidification therapy, Mucociliary clearance

Abbreviations: CON, control group, COPD, chronic obstructive pulmonary disease, ECCS, European Community for Steel and Coal, ECG, electrocardiogram, FEV₁, forced expiratory volume in 1 s, FiO₂, fraction of inspired oxygen, FVC, forced vital capacity, HRCT, high-resolution computed tomography, IC, inspiratory capacity, ICS, inhaled corticosteroids, LABA, long acting beta 2 agonists, LTHT, long-term humidification therapy, LTOT, long-term oxygen therapy, MRC, Medical Research Council, 6MWD, 6min walk distance, PEEP, positive end expiratory pressure, QOL, quality of life, SaO₂, oxygen saturation, SGQR, St George's respiratory questionnaire, TREAT, treatment group