PAP Therapy May Improve Cognition in Patients With Parkinson Disease With OSA

Positive airway pressure (PAP) therapy may improve cognition and sleep quality in patients with Parkinson disease (PD) with obstructive sleep apnea (OSA), according to the findings of a study published in Sleep.

Researchers in Montreal, Canada, conducted single-blind, parallel group clinical trial of auto-PAP (APAP) vs nasal dilator strips (NDS) to assess the effects of PAP in individuals with PD. The researchers recruited participants from the McGill University Movement Disorder Clinic and from a general neurology clinic.

Participants were enrolled if they had a diagnosis of PD, a clinical impression of mild cognitive impairment (MCI) with a Montreal Cognitive Assessment (MoCA) score of 27 or higher, and OSA with a respiratory disturbance index (RDI) of 15 or more per hour.

The primary outcome was the mean change in MoCA score from baseline to 6 months, and the secondary outcomes included change in quality of life (QoL) and nonmotor symptom (NMS) burden. Complete subject blinding was not possible, but participants assigned to the NDS (control) group were not told that NDS are a placebo. A t-test under intention-to-treat (ITT) and linear regression models were employed for statistical analysis.

A total of 48 participants were included in the treatment group (mean age, 66.0 years; men, 77%; mean body mass index [BMI], 27.4), and 46 were included in the control group (mean age, 68.8 years; men, 61%; mean BMI, 28.8) for the ITT analysis. At 6 months, MoCA scores improved in the treatment arm by a mean 0.60 points (SD, 2.37) and declined in the NDS group by a mean 0.39 points (SD, 2.79). No statistical differences were observed within or between groups.

After adjusting for age, sex, and BMI, the difference in MoCA score change between groups was 1.28 (95% CI, 0.18-2.37), suggesting an improvement in the PAP vs control group.

Adjusting for baseline depression scores, hypertension, and change in psychoactive medication showed a difference in MoCA between groups of 1.44 (95% CI, 0.09-2.79). A subset analysis of 59 participants with no change in medication for 6 months showed a MoCA improvement of 1.46 points (95% CI, 0.01-2.90) in the PAP vs control group. Per-protocol analysis showed an adjusted between-group MoCA score difference of 1.43 (95% CI, 0.05-2.81) in the PAP (n=33) vs control (n=41) group.

Significant improvements were observed in the PAP group for NMS, depression scores, and sleep quality; no such improvements were observed in the control group. Individuals in the PAP group had improvement in several executive and psychomotor tests. Improvements in letter sequencing (per protocol only), number/letter switching, 2 language tasks, and right hand tapping (ITT only) were documented in the control group.

Study limitations included a higher than anticipated non-completion rate due to the COVID-19 pandemic.

“In conclusion, this is the largest and longest duration RCT to date of PAP treatment of OSA in a neurodegenerative condition. Our results suggest those PD patients who are able to adhere to this therapy over a six-month period benefit with respect to cognition, primarily in executive and psychomotor function, and also sleep quality, depression symptoms, and non-motor symptoms globally, as well as motor function,” the researchers concluded.

Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.