Table 1.

Factors of Influence on CPAP^* Adherence

Factor	Relationship to Course of Treatment			Caveat
	Pre-CPAP Exposure	Initial CPAP Exposure	Home CPAP Treatment
Disease & Patient Characteristics	Disease Severity			Weak but consistent factor of CPAP use
	Sleepiness			Weak but consistent factor of CPAP use
	Upper Airway Patency			Baseline assessment with acoustic rhinometry; decreased nasal volume/patency may influence initial acceptance of CPAP and reduce overall use of CPAP
		Depression, Mood, Personality Type	Depression, Mood, Personality Type	Influence perceptions of symptoms, response to treatment, and side effects which may deter CPAP use
	Race			Limited evidence in groups other than African Americans, who tend to use CPAP less than Caucasians
	SES*			Neighborhood of residence important and may suggest socioenvironmental factors influential on CPAP use
Treatment Titration Procedure		Auto-titrating CPAP		Subgroups that may benefit include younger persons, those with persistent side effects, and those who require high pressure
Technological Device Factors & Side Effects		Heated Humidification	Heated Humidification	Generally recommended for all CPAP users; particularly important for those with oronasal side effects at treatment outset and/or with CPAP use
			Flexible Pressure	Add-on therapy in non-adherent users
	Claustrophobia			Decreases over time with persistent CPAP use
Psychological & Social Factors		Self-efficacy	Self-efficacy	Belief in ability to use CPAP formed at education and with early CPAP exposure is important
		Outcome Expectations	Outcome Expectations	Realistic expectations for improvements with CPAP influence use
			Social Support	Provide feedback to CPAP user re: noticeable improvements; Pressure from spouse may deter use
	Disease & Treatment- specific Knowledge	Disease & Treatment- specific Knowledge	Disease & Treatment- specific Knowledge	Contribute to perceptions of OSA* and CPAP but alone likely not influential
			Decisional Balance (pros/cons)	If negative aspects of CPAP > positive, use of CPAP may be low
			Active Coping Style	Planful problem- solving and confrontative coping positive influence on CPAP use
			Disease- specific Risk Perception	Contribute to perceptions of OSA and CPAP but alone likely not influential
			Presence of Bed Partner	Improved sleep quality of bed partner with patient’s CPAP use associated with use of treatment

^*CPAP – Continuous Positive Airway Pressure; SES – Socioeconomic Status; OSA – Obstructive Sleep Apnea CPAP Adherence Interventions