Treatments for Obstructive Sleep Apnea

Improved CPAP Treatment

As stated previously, CPAP pneumatically splints the upper airway, thus preventing it from collapsing during sleep. However, CPAP is not well-tolerated. Modifications to standard CPAP to increase adherence have been met with disappointing results. Humidification with heated tubing delivering heated moistened air did not increase compliance compared to standard CPAP [19]. CPAP was also compared with auto-adjusting CPAP (APAP), where respiration is monitored and the minimum pressure of air is applied to splint the upper airway open. In a meta-analysis, APAP only had very small effect on compliance [20]. Lastly, reduction in pressure during expiration was investigated, and a meta-analysis showed no effect [21,22]. However, recent advances in CPAP delivery give hope to increasing compliance. The S9CPAP machine (Resmed, San Diego, CA), which combines a humidification system and an APAP, showed increased compliance compared to standard CPAP. Compliance increased by an average of 30 minutes per night, and variance of daily usage decreased (eg, patients used it more day-to-day) [23]. However, a randomized blinded study needs to be conducted to corroborate these results.

Promoting CPAP Adherence Through Patient Interventions

Educational, supportive, and behavioral interventions have been used to increase CPAP adherence and have been thoroughly reviewed via meta-analysis [24]. Briefly, 30 studies of various interventions were included and demonstrated that educational, supportive, or behavioral interventions increased CPAP usage in OSA-naive patients. Behavioral interventions increased CPAP usage by over an hour, but the evidence was of “low-quality.” Educational and supportive interventions also increased CPAP usage, with the former having “moderate-quality” evidence [24]. However, whether increased CPAP usage had an effect on symptoms and quality of life was statistically unclear, and the authors recommended further assessment [24]. Three more studies on interventions to increase CPAP usage have been conducted since the aforementioned review. In a randomized controlled study, investigators had OSA patients participate in a 30-minute group social cognitive therapy session (eg, increasing perceived self-efficacy, outcome expectations, and social support) to increase CPAP adherence. Compared to a social interaction control group, there was no increase in adherence rates [25]. In another smaller randomized controlled study that used a social cognition model of behavioral therapy, there were small increases of CPAP usage. At 3 months, the social cognitive intervention increased CPAP usage by an average of 23 minutes per night, increased the number of individuals using their CPAP machine for more than 4 hours compared to standard care group, and decreased symptom of sleepiness [26]. And lastly, a preliminary study looked at increasing adherence rates by utilizing easily accessible alternative care providers, such as nurses and respiratory therapists, for the management of OSA [27]. Though this study had no control group, it did show that good adherence and a decrease in symptoms of sleepiness could be achieved with non-physician management of OSA [27]. A randomized controlled study will be needed to validate the use of alternative care providers.

Interventions have shown some success in increasing adherence rates, but the question remains on who should receive those interventions. Predicting which OSA patients are in most need of an intervention has been studied. A recent study used a 19-question assessment tool called the Index of Nonadherence to PAP to screen for nonadherers (OSA patients who used CPAP for less than 4 hours a night, after 1 month of OSA diagnosis). The assessment tool was 87% sensitive and 63% specific at determining those OSA patients who would not adhere to CPAP treatment [28]. Another study investigated the reliability and validity of a self-rating scale measuring the side effects of CPAP and their consequences on adherence [15]. The investigators showed that the scale was able to reliably discriminate between those who adhered to CPAP treatment and those that did not [15]. Both of these scales can be used to screen OSA patients that need interventions to increase CPAP adherence. Lastly, a recent systematic review showed that a user’s CPAP experience was not defined by the user but by the user’s health care provider, who framed CPAP as “problematic” [29]. The authors argue that users of CPAP are “primed” to reflect negatively on their CPAP experience [29]. Interventions can be used to change the way OSA patients think or feel about their CPAP machines.