Health & Wellness

Sleep Apnea and MS

By Tiffany Braley, M.D.

If you have MS, chances are that you have experienced at least some problems with your sleep. Up to 60 percent of people with MS experience at least one sleep disturbance.
One of the most common sleep problems experienced by everyone – those with MS and without – is a disorder known as obstructive sleep apnea (OSA). Obstructive sleep apnea occurs when the upper airway partially or totally collapses during sleep, leading to a diminished or complete blockage of airflow, despite an effort to breathe. As the body struggles to restore airflow through the blockage, you partially awaken and sleep is interrupted. Another, less known, form of sleep apnea is known as central sleep apnea (CSA). Unlike OSA, CSA arises because of a lack of effort to breathe during sleep. Both conditions can lead to poor sleep quality and decreased blood oxygen levels throughout the night.
For reasons not yet fully understood, MS patients are at a higher risk for both OSA and CSA than those without MS. Early research suggests MS patients may be at higher risk for these conditions because of changes in brainstem function caused by MS. The brainstem controls muscles that keep the airway open when we sleep, as well as our drive to breathe when we are not awake. In MS, demyelinating lesions can form in the brainstem, disrupting the pathways that control upper airway muscles and respiratory drive.
Several medications that are commonly used in MS may also worsen each of these conditions. Medications that are used for muscle spasticity, sedatives, and certain opioid-based pain medications may all contribute to obstructive or central apnea severity. Aside from MS, other physical characteristics that may put patients at higher risk for OSA include obesity, increased neck size, age of more than 50, and male gender. Certain anatomical features in the upper airway, including a large tongue and narrow palate can also contribute to OSA risk.
Although people with MS may be at higher risk for OSA or CSA, OSA is far more common. Up to 50 percent of those with MS may suffer from OSA; yet most individuals with sleep apnea are undiagnosed, and therefore, untreated. It is therefore imperative that you know the symptoms and risk factors associated with OSA, and discuss them with your doctor, to prevent the many short- and long-term consequences of sleep apnea.
Fatigue and cognitive impairment
The consequences of sleep apnea, and OSA in particular, are far reaching. Some of the most common consequences that affect MS and non-MS patients alike include and increased risk of cardiovascular disease (high blood pressure, heart attack, and stroke), depression, diabetes, motor vehicle accidents, decreased work productivity, and diminished quality of life. Obstructive sleep apnea can profoundly affect daily function and exacerbate chronic symptoms experienced by persons with MS. Chief among them? Fatigue.
This highly debilitating symptom imposes significant socioeconomic consequences, and is a leading cause of diminished quality of life. Recent studies suggest that several sleep disorders, including OSA, contribute to fatigue in MS. Early data also suggest that successful treatment of OSA and other sleep disorders may improve fatigue and sleepiness; yet these sleep disorders remain significantly under-recognized in the MS population.
Cognitive impairment – difficulties with thinking, information processing, memory, and verbal expression –  affect up to 70 percent of people with MS. Interestingly, many of these symptoms have also been linked to OSA. Recent studies have shown that OSA is associated with subjective and objective cognitive problems in both MS and non-MS patients.
Treatment options
Given the effect of OSA on health and well-being, all individuals with MS should discuss symptoms of sleep apnea with their healthcare provider.
Symptoms of sleep apnea include:
• Snoring
• Pauses in breathing
• Gasping or choking upon awakening
• Nonrestorative sleep
• Excessive daytime sleepiness or fatigue
• Cognitive disturbances
• Nighttime awakenings
Difficulty with swallowing or speech production (which may be signs that MS has affected your brainstem), or the presence of brainstem lesions on your MRI, may also signal higher risk for OSA or CSA.
An overnight sleep study is needed to diagnose sleep apnea. This is typically done in a sleep laboratory, so that your sleep and breathing can be measured throughout the night. In some cases, sleep studies can be done with equipment that you take home. The sleep study should not be painful and generally has few complications.
Fortunately, sleep apnea is a treatable condition. The most effective treatment for OSA, known as positive airway pressure therapy, uses a mask to blow air into the upper airway, splinting it open during sleep. The air pressure may be constant (continuous positive airway pressure, or CPAP), may use different pressures when you inhale and exhale (bilevel positive airway pressure therapy, or BiPAP), or might be self-adjusting to your breathing within a set range of pressures (AutoPAP). There are multiple choices and sizes of sleep masks, and your healthcare provider will work with you to find the most comfortable mask for you.
Healthy sleep is an essential part of physical and mental well-being. Discussions about sleep should be a routine part of your comprehensive MS care. Although MS is associated with many chronic symptoms, some of these symptoms may be, at least in part, exacerbated by sleep disturbances, and may improve when the sleep disturbances are treated.