CPAP Improves Polysomnography Parameters, Quality of Life in OSA

A study published in Sleep and Breathing found that the continuous positive airway pressure (CPAP) machine was able to normalize polysomnographic (PSG) parameters and improve quality of life more effectively than the mandibular advancement device (MAD) for patients with mild obstructive sleep apnea (OSA).

Mild OSA is highly prevalent in adults, and some studies have demonstrated a risk of excessive daytime sleepiness in these individuals. The CPAP machine has proven to be effective in reducing in excessive daytime sleepiness, whereas MAD is effective in achieving greater adherence in patients who did not adhere to CPAP. The study aimed to determine which treatment was most effective in patients with mild OSA.

Those who had a confirmed diagnosis of mild OSA were selected at time of enrollment. Participants who had a BMI of less than or equal to 35 kg/m², were aged 18 to 65 years, and had a diagnosis of mild OSA were included in this study. Patients were excluded if they had dental conditions that didn’t allow use of MAD, grade III nasal septum deviation, alcohol or psychoactive drug use, smoking, neurological or psychiatric conditions, other sleep disorders, shift work, or previous treatment for OSA.

All participants were examined, had a polysomnography (PSG) test, and answered questionnaires and assessments for this study. The questionnaires used for this study included the Pittsburgh Sleep Quality Index, Berlin Sleep Questionnaire, Epworth Sleep Scale, Beck Anxiety Inventory and Beck Depression Inventory, and Stanford Sleepiness Scale, among others.

There were 79 participants in this study split into a CPAP group with 31 patients, a MAD group with 25 patients, and a control group with 23 patients. All patients were followed at 6 and 12 months, although the 6-month follow-up was missing a PSG reading.

Adherence to treatment was higher in the MAD group compared with the CPAP group. The CPAP group demonstrated a decrease in arousal index from baseline to 6 months, but an increase was identified between 6 and 12 months. The arousal index in the CPAP group from 6 to 12 months was lower than in the control group.

Both the MAD and CPAP groups had a lower respiratory disturbance index (RDI) and apnea/hypopnea index (AHI) when comparing baseline to 6 months and baseline to 12 months. There was a higher RDI and AHI in the control group compared with CPAP and MAD in those 2 time periods. MAD had a higher RDI than CPAP at 6 months.

Oxyhemoglobin saturation increased in the CPAP group from baseline to 12 months, and was higher than in the MAD and control groups at 12 months. There was no significant difference between groups and times for sleepiness. Total fatigue was reduced from baseline to 6 months and baseline to 12 months in the MAD and CPAP groups. However, there was no difference found between the 2 groups.

There was improvement in social domain outcomes of the quality-of-life questionnaires in both the CPAP and MAD groups, but improvement was greater in the CPAP group. An intention-to-treat analysis found that those in the CPAP group had higher scores compared with the control group at the 12-month follow-up.

There were some limitations to this study. Mild OSA has various definitions in literature, which means that patients with mild OSA could have been excluded due to differing definitions of the condition. There was also no measure of subjective sleepiness at baseline, which limited the ability to demonstrate improvement over time. There was also no objective monitoring of adherence to the MAD.

The researchers concluded that CPAP was better at normalizing PSG parameters and could improve quality of life in patients with mild OSA when compared with MAD. Daytime sleepiness, sustained attention, fatigue, and mood were no different between the 2 treatments.

Reference

Luz GP, Badke L, Nery LE, et al. Effect of CPAP vs. mandibular advancement device for excessive daytime sleepiness, fatigue, mood, sustained attention, and quality of life in patients with mild OSA. Sleep Breath. Published online August 10, 2022. doi:10.1007/s11325-022-02694