Effect of long-acting levodopa on obstructive sleep apnea in Parkinson’s disease
The Research Institute of McGill University Health Centre
Sleep disorders are common in Parkinson’s disease (PD), including obstructive sleep apnea (OSA). OSA consists of recurrent complete or partial obstruction of the upper airway (throat) during sleep, leading to poor quality sleep and reduced blood oxygen levels. This results in disrupted sleep and daytime sleepiness, with multiple adverse clinical consequences such as cardiovascular disease and impaired cognitive function. Continuous Positive Airway Pressure (CPAP) is the mainstay of treatment. While effective, it can be uncomfortable and difficult to use, particularly in patients with physical or cognitive difficulties as may be the case in PD.
In PD, OSA may be in part due to to abnormal function of upper airway muscles. This might be correctable using PD medication (e.g. levodopa). We have previously observed that patients with PD taking long-acting levodopa at bedtime have less OSA than those not taking this medication. In this study, we will measure the effect of long-acting levodopa on breathing during sleep in patients with PD and OSA, to determine if this medication can improve OSA in PD. Participants will take long-acting levodopa and placebo for 2 weeks each, in a randomly determined order, separated by a rest period. Polysomnographies (sleep studies) will be done to determine the effect of long-acting levodopa on breathing in sleep compared to placebo.
Relevance to the acceleration of therapeutics for neurodegenerative diseases of aging
OSA has adverse consequences in the brain, for example promoting neuroinflammation. It accelerates cognitive decline in the general population, and might impact on the course of PD. On the other hand, OSA might be a consequence of PD, resulting in a feed-forward loop potentially accelerating PD neurodegeneration. If long-acting levodopa can reduce severity of OSA in PD, future benefits may be two-fold. First, this treatment could result in improved sleep in patients with PD and OSA, leading to improved symptoms and quality of life. Second, it could lead to further research to determine whether correcting OSA can delay progression of PD, especially cognitive dysfunction.
Long-acting levodopa taken at night may reduce the severity of OSA in patients with PD who have OSA. It might provide a treatment option for those who are unable to use CPAP. With OSA partially or completely corrected, this might lead to better sleep quality, quality of life and possibly cognitive function. This pilot study seeks to determine the effect of long-acting levodopa on OSA as measured on polysomnography). The study will also look at effects of nighttime long-acting levodopa, in preliminary fashion, on clinical outcomes such as sleepiness and cognitive function.