title: Effect of Heated Humidification on CPAP Therapy Adherence in Subjects With Obstructive Sleep Apnea With Nasopharyngeal Symptoms.
abstract: BACKGROUND
  The addition of heated humidification to CPAP has been shown to improve nasal adverse effects in subjects with obstructive sleep apnea (OSA). However, current data regarding improvement in CPAP adherence is conflicting. Furthermore, there are no data from a tropical climate area with a high humidity level.
  
  
  METHODS
  In this prospective randomized crossover study conducted in Thailand, subjects with moderate to severe OSA with nasopharyngeal symptoms post-split-night study were enrolled in the study. Subjects were randomly assigned to receive CPAP with or without heated humidification for 4 weeks and then crossed over. Information on CPAP adherence, quality of life assessed by the Functional Outcomes of Sleep Questionnaire, nasopharyngeal symptoms assessed by a modified XERO questionnaire, and bedroom ambient humidity and temperature data were obtained.
  
  
  RESULTS
  Data were collected on 20 subjects with OSA during the period of January to December 2014. Although the addition of heated humidification appeared to improve average hours of use for all days when compared with conventional CPAP, the difference was not statistically significant (CPAP with heated humidification = 4.6 ± 1.7 h/night; conventional CPAP = 4.0 ± 1.7 h/night, P = .1). However, the addition of heated humidification improved CPAP adherence on the days of use (5.5 ± 1.5 h/night) compared with conventional CPAP (5.2 ± 1.4 h/night), P = .033. Quality of life was also improved according to the Functional Outcomes of Sleep Questionnaire score (median 17.6 [interquartile range 3.5]) in the heated humidification group compared with conventional CPAP group (median 17.6 [interquartile range 4.5]), P = .046. Significant reduction in the dry throat/sore throat symptom was noted only when CPAP with heated humidification was used.
  
  
  CONCLUSIONS
  Even in a tropical climate area, CPAP adherence and quality of life appeared to improve when heated humidification was employed in subjects with moderate to severe OSA with nasopharyngeal symptoms post-split-night polysomnography. The improvement may be related to a reduction in the dry throat/sore throat symptom.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Medicine, Faculty of Medicine, Chulalongkorn University and the Excellence Center for Sleep Disorders, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand.
authors.forename: Chuleekorn
authors.initials: C
authors.lastname: Soudorn
authors.affiliation: Excellence Center for Sleep Disorders, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand and the Section for Mathematics, Faculty of Science and Technology, Rajamangala University of Technology Suvarnabhumi, Phranakhon Si Ayutthaya, Thailand.
authors.forename: Dittapol
authors.initials: D
authors.lastname: Muntham
authors.affiliation: Section of Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Sirimon
authors.initials: S
authors.lastname: Reutrakul
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Medicine, Faculty of Medicine, Chulalongkorn University and the Excellence Center for Sleep Disorders, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand. narichac@hotmail.com.
authors.forename: Naricha
authors.initials: N
authors.lastname: Chirakalwasan
mesh_terms: D000328:Adult; D045422:Continuous Positive Airway Pressure / Q000009:adverse effects / Q000379:methods*; D018592:Cross-Over Studies; D005260:Female; D006358:Hot Temperature; D006801:Humans; D006813:Humidity; D008297:Male; D008875:Middle Aged; D015508:Nasal Obstruction / Q000209:etiology / Q000517:prevention & control; D010349:Patient Compliance; D010612:Pharyngitis / Q000209:etiology / Q000517:prevention & control; D011446:Prospective Studies; D011788:Quality of Life; D020181:Sleep Apnea, Obstructive / Q000628:therapy*; D013696:Temperature; D013785:Thailand; D014987:Xerostomia / Q000209:etiology / Q000517:prevention & control
keywords: CPAP; adherence; heated humidification; obstructive sleep apnea; quality of life