Parkinson’s disease (PD) often disrupts sleep patterns and quality of sleep. Some studies have found as high as 88% of people with PD have sleep disturbances, and the disruption in sleep is one of the symptoms of PD that most impacts quality of life.
Sleep disturbances are frequently complex, and many people with PD may have several factors that are impacting their sleep. Sleep disturbances may be related to factors including depression, poor sleep hygiene, having to wake to urinate (nocturia), pain, muscle contractions that cause twisting or repetitive movements (dystonia), muscle rigidity or difficulty moving (akinesia), difficulty turning in bed, reactions to medications, and vivid dreaming. In addition, many people with PD have other primary sleep disturbances like REM sleep behavior disorder, periodic limb movements of sleep, and restless legs syndrome.1
While there are some medications that can help with sleep problems, these medications should be discussed with a movement disorders specialist who is trained to know if these medications will be helpful or may make PD symptoms worse. Physicians trained in movement disorders also know if certain medications taken for PD symptoms are contributing to the sleep problems.
Insomnia is defined as an insufficient amount of sleep almost every night. Insomnia may be classified as difficulty falling asleep, difficulty staying asleep, or awakening too early. People with PD may experience any of these, although the most common is staying asleep, affecting approximately 74-88% of patients. Depression is one of the two most common causes of insomnia, and many people with PD experience depression. There are a variety of medications that can help with insomnia, including benzodiazepines, non- benzodiazepine hypnotics, antihistamines, and antidepressants.1
REM sleep behavior disorder
REM Sleep Behavior Disorder (RBD) is characterized by abnormal behavior during rapid eye movement (REM) sleep, causing the person to act out their dreams. The person with RBD may shout, scream, punch, or kick, usually responding to a perceived attacker in their dream. Many researchers believe that RBD may be an early manifestation of PD, appearing as an early symptom before the more classic motor symptoms of PD are noticeable. REM sleep behavior disorder is diagnosed by a nighttime sleep study. Management of RBD is important to minimize the potential for injury both to the patient and their bed partner. Nightly therapy with melatonin or clonazepam can help, and people with PD are advised to make changes to the bedroom environment (such as moving sharp or objects that could cause injury out of the way).2
Restless legs syndrome and periodic limb movements of sleep
Restless legs syndrome (RLS) usually occurs as one is trying to fall asleep and is characterized by an unpleasant, restless feeling that is only relieved by moving the legs. Periodic limb movements of sleep (PLMS) are rhythmic moving or jerking of the limbs during sleep. Both RLS and PLMS affect the quality and quantity of sleep. Medications are available that can help these syndromes. Some people also experience relief with an increase in dopaminergic treatment.1
Sleep apnea causes a person to awaken (at least partially) to restore breathing. While the person remains in a light sleep and may not be aware of these awakenings, the frequency of awakenings disrupts the quality of sleep, causing little restorative sleep and extreme daytime sleepiness. The bed partner may also be affected and may be more aware of the loud snoring, gasping, and periods of no breathing experienced by the patient. Sleep apnea has been found in as many as 50% of people with PD. It is diagnosed by a nighttime sleep study and can be treated with a nighttime apparatus like a CPAP (continuous positive airway pressure) machine.1
Many people with PD experience an increase in dreaming, and some studies suggest the vivid dreams may be related to dopaminergic therapies. Some people are not bothered by the vivid dreams. Those who are bothered may experience relief with a lower dose of dopaminergic therapy at night. Another medication that can be used is quetiapine.1
Excessive daytime sleepiness
Excessive Daytime Sleepiness (EDS) is characterized by a tendency to fall asleep during the day. This is different than fatigue, which presents as tiredness or weakness in initiating or sustaining mental and physical tasks. Both EDS and fatigue can be caused or worsened by insomnia, medications that cause drowsiness, other sleep disorders, and depression. Evaluation of EDS begins with assessing the individual’s sleep, usually by a nighttime sleep study, as well as reviewing all medications and assessing for depression or anxiety. Treatment may include behavioral and lifestyle approaches, including regular mild exercise and exposure to intense light in early mornings. There are medications that may provide a modest benefit to patients experiencing EDS.1
Sleep attacks cause the person to fall asleep suddenly with little warning, which can be particularly dangerous if the person is walking down stairs or driving. Estimates on the prevalence of sleep attacks in people with PD vary from 0 to 30%. Sleep attacks are believed to be an effect of dopamine agonists and dopamine replacement therapies. Treatment includes behavior changes (like eliminating driving) or reducing or stopping dopamine agonist therapy.1