Does humidification reduce exacerbations for people with COPD and bronchiectasis?

INTERVENTION: Daily 2 hours humidifcation treatment over a 12 month treatment period. Humidified air, fully saturated at 37 degree Celsius is delivered at 20 L/min or 25 L/min NHF via a nasal cannula. CONDITION: Chronic obstructive pulmonary disease. bronchiectasis PRIMARY OUTCOME: To determine whether the delivery of humidified air for 2 or more hours per day at home can reduce exacerbation frequency for patients with COPD and bronchiectasis. SECONDARY OUTCOME: The secondary outcome is to determine whether the delivery of humidified air for 2 or more hours per day: Improves perceived quality of life over the 12 months The secondary outcome is to determine whether the delivery of humidified air for 2 or more hours per day: Improves subject's exercise capacity (6 Minute Walk Test) over the 12 months The secondary outcome is to determine whether the delivery of humidified air for 2 or more hours per day: Improves subject's inflammatory markers (sputum cell counts) over the 12 months The secondary outcome is to determine whether the delivery of humidified air for 2 or more hours per day: Improves subject's lung function over the 12 months. Spirometry was used to assess patient's FEV1 according to ATS/ERS guideline. The secondary outcome is to determine whether the delivery of humidified air for 2 or more hours per day: prolongs time to first exacerbation. The secondary outcome is to determine whether the delivery of humidified air for 2 or more hours per day: Reduces hospital admissions for respiratory conditions. The secondary outcome is to determine whether the delivery of humidified air for 2 or more hours per day: Reduces the number of exacerbation days over the 12 months. INCLUSION CRITERIA: COPD; FEV1<70% and FEV1/FVC ratio <70%, and, > 2 exacerbation over the last 12 months, and > 5mL daily sputum production. Bronchiectasis; diagnosis of bronchiectasis confirmed by CT, and, > 2 exacerbation over the last 12 months. All subjects were recruited when stable with no sign of an exacerbation for at least 4 weeks.