Effect of Heated Humidity With Thermosmart™ Compared to an Intranasal Steroid in Improving Compliance and Nasal Symptoms in Patients Using Continuous Positive Airway Pressure

1. CPAP compliance will be significantly higher in both the heated humidity with Thermosmart™ and the nasal steroid phases compared to the double placebo phase.
2. CPAP compliance will be comparably improved in the heated humidity with Thermosmart™ phase versus the nasal steroid phase.
3. Improvement in nasal symptoms in using CPAP will be significantly improved in both the heated humidity with Thermosmart™ and the nasal steroid phases compared to the double placebo phase, and comparable between the heated humidity with Thermosmart™ phase versus the nasal steroid phase.
4. Secondary to improvements in CPAP compliance, measures of daytime functioning and quality of life will improve in the heated humidity with Thermosmart™ versus double placebo.

Eligible participants will undergo this double-blind, placebo controlled, single-blind double placebo run-in, crossover trial to determine the efficacy of heated humidity with Thermosmart™ in improving compliance and nasal symptoms in patients using CPAP versus a nasal steroid and placebo (heated humidity, nasal steroid placebo) phases. After successful screening, participants will undergo a two week single-blind double placebo run-in phase using heated humidity and a nasal steroid placebo. The double-blind treatment phase will last a total of six weeks. Participants will undergo both phases: three weeks using heated humidity with Thermosmart™ and nasal steroid placebo and three weeks using a nasal steroid with a heated humidifier. Treatment phases will be counterbalanced. Study participation will last a total of 8 weeks from screening to completion of double-blind treatment.

Eligibility Criteria:
Inclusion Criteria:

* Between the ages of 18-65
* Diagnosis of obstructive sleep apnea (OSA) with apnea/hypopnea index (AHI) \> 15/hr
* Currently using CPAP therapy and within 3 weeks to 12 months of initial CPAP titration
* Based on the CPAP nasal symptom questionnaire, a score of at least 3 (sometimes) for at least one of the following nasal symptoms related to their sleep apnea and CPAP usage: nasal congestion, runny nose, sneezing, or nasal irritation
* Willingness to tolerate and continue therapy with nCPAP
* Successfully titrated on nCPAP in a sleep center to a pressure between 6-16 cmH2O
* Willingness to comply and complete study related procedures
* Fluent in the English language

Exclusion Criteria:

* Co-morbid medical condition that is either medically significant and unstable, would interfere with the patient's ability to routinely use CPAP, or is a contraindication for use of a nasal steroid
* Women who are pregnant or who may potentially become pregnant during the course of the research trial.
* CPAP compliance over the past three weeks at screening \> 5 hours/night, suggesting no compromised CPAP usage due to adverse nasal symptoms
* Wake resting SaO2 \< 90%
* Currently using Bi-Level therapy, supplemental oxygen with CPAP therapy, or using a pressure outside inclusion criteria
* Currently using a Full-Face mask for CPAP therapy
* Current or prior use of the Fisher Paykel 604 CPAP machine with Thermosmart™ heated humidity.
* Patients who were never prescribed a heated humidifier with their CPAP machine (i.e. no humidifier or passover humidifier).
* Intranasal steroid treatment within the previous six months. Patient's currently taking intranasal steroid treatment cannot wash-out of steroid treatment to be included nor if patients have used nasal steroid treatment while on CPAP therapy
* Current upper airway tract infection, influenza, respiratory infection at time of screening or nasal surgery within 90 days of screening
* Prior surgical intervention for obstructive sleep apnea
* Currently taking medications that would be contraindicated to using a nasal steroid. Patients taking hypnotic or wake promoting therapy can participate if they have been on a stable dose prior to CPAP therapy and willing to maintain current dose as prescribed.
* Shift or rotating shift workers or individuals who routinely cannot contribute at least 6 hours/night to sleep/attempting therapy
* Additional sleep disorder that would interfere with routine use of CPAP