Study objective: To determine whether the addition of heated humidification at treatment initiation with nasal continuous positive airway pressure (CPAP) would lead to better CPAP compliance and improve quality of life and subjective sleepiness in patients with sleep apnea.
Design: Randomized controlled trial.
Setting: An academic sleep center located at a Veterans Affairs hospital.
Patients: Ninety-eight patients with obstructive sleep apnea who had not received nasal CPAP previously.
Measurements and results: Patients received heated humidification at CPAP initiation in the treatment group. In the control group, patients could receive heated humidification only if they had upper airway symptoms that could not be treated successfully with simpler measures. Patients were followed up at 1 month, 3 months, and 12 months. Outcome measures were compliance with nasal CPAP (mean hours per night at effective pressure), quality of life as measured by the Calgary sleep apnea quality of life index, subjective sleepiness measured with the Epworth sleepiness scale, and CPAP side effects. There was no difference in CPAP compliance between groups. Quality of life and subjective sleepiness improved in both groups with nasal CPAP therapy, but there was no difference in the extent of improvement between groups. The overall CPAP side effect score was similar in both groups, but individual symptoms of dry nose and dry mouth and throat were significantly lower in the heated humidification group.
Conclusions: The addition of heated humidification when nasal CPAP was instituted did not lead to better compliance, greater improvement in sleepiness, or improved quality of life, but was associated with fewer symptoms attributable to the upper airway.