ABSTRACT
In myasthenia gravis respiratory function is often disturbed in the night, especially during REM sleep, despite of normal daytime respiratory function. Nevertheless, nocturnal respiratory problems are rarely diagnosed. Sleepiness, concentration and memory problems can be symptoms of a sleep related breathing disorder. Reports of reduction of REM sleep, memory dysfunction, and detection of acetylcholine receptor (AchR)-antibodies in the cerebrospinal fluid have lead to the hypothesis of a central nervous system involvement in myasthenia gravis. Possible mechanisms are centrally acting AchR-antibodies, unspecifically acting cytokines and hypoxia, possibly the most important influence upon REM sleep reduction and impaired cognitive function. In a patient presenting possible CNS-involvement (cephalea, fatigue, concentration and memory problems), a polysomnographic investigation should therefore be performed to detect a sleep related breathing disorder.
Subject(s)
Memory Disorders/etiology , Myasthenia Gravis/complications , Sleep Apnea Syndromes/etiology , Sleep, REM , Autoantibodies/cerebrospinal fluid , Cholinesterase Inhibitors/pharmacology , Humans , Myasthenia Gravis/cerebrospinal fluid , Myasthenia Gravis/metabolism , Receptors, Cholinergic/immunology , Sleep Apnea Syndromes/cerebrospinal fluidABSTRACT
This literature review shows the current knowledge of health effects on humans concerning static, low frequency electric and magnetic fields and high frequency electromagnetic fields up to 300 GHz. Basic physical knowledge and the current thresholds are demonstrated. Different frequency ranges of electromagnetic fields, their natural and technical origins and the different biological effects, especially possible hazards such as cancerogenity or risks for the brain, are discussed. Open questions and future research aspects are demonstrated. Finally electrosensibility and psychological aspects are shown.
Subject(s)
Brain/radiation effects , Electroencephalography/radiation effects , Electromagnetic Fields/adverse effects , Leukemia, Radiation-Induced/etiology , Neoplasms, Radiation-Induced/etiology , Animals , Dose-Response Relationship, Radiation , HumansABSTRACT
19 middle-aged patients with myasthenia gravis (MG) and 10 age, sex and education-matched controls underwent overnight polysomnography and neuropsychological testing, in order to test the hypothesis of whether cognitive dysfunction and REM-sleep disturbance in MG are related to nocturnal respiratory problems or caused by CNS-involvement. We observed in 60% of the myasthenics central type of sleep apneas and hypopneas with resulting oxygen desaturations occurring during REM-sleep, but no decrease of REM sleep. In neuropsychological testing, we found normal vigilance performance but decreased memory function in the myasthenics. In comparison with patients without sleep apnea, myasthenics with sleep apneas had an impaired memory function.
Subject(s)
Cognition Disorders/physiopathology , Myasthenia Gravis/physiopathology , Sleep Apnea Syndromes/physiopathology , Adult , Attention/physiology , Brain/physiopathology , Cognition Disorders/diagnosis , Female , Humans , Male , Mental Recall/physiology , Middle Aged , Myasthenia Gravis/diagnosis , Neuropsychological Tests , Polysomnography , Pulmonary Ventilation/physiology , Sleep Apnea Syndromes/diagnosis , Sleep Stages/physiology , Sleep, REM/physiologyABSTRACT
Hypersomnia (excessive sleepiness) accompanies many diseases. 14% of the total Austrian population regularly have problems staying awake during the day or are prone to taking spontaneous naps. Hypersomnia is a symptom of the sleep apnea syndrome, which is a risk factor for cerebrovascular disorders. Daytime sleepiness is also a characteristic symptom of narcolepsy, idiopathic hypersomnia, episodic hypersomnia, and many more neurological or psychiatric disorders; it can also be drug induced. Involvement of brain structures which are essential for the regulation of the sleep wake cycle as a result of neurological disorders can likewise lead to hypersomnia. Symptomatic treatment is necessary when treatment of the causal factors is not possible or no improvement has been achieved.
Subject(s)
Disorders of Excessive Somnolence/etiology , Nervous System Diseases/complications , Sleep Apnea Syndromes/complications , Austria/epidemiology , Cerebrovascular Disorders/etiology , Cerebrovascular Disorders/prevention & control , Circadian Rhythm , Disorders of Excessive Somnolence/epidemiology , Disorders of Excessive Somnolence/psychology , Female , Humans , Male , Risk FactorsABSTRACT
19 middle-aged patients with myasthenia gravis (MG) and 10 age-matched controls underwent overnight polysomnography and neuropsychological testing, in order to assess the frequency, degree, type and risk factors of sleep apneas in MG and to show their influence on sleep profile and neuropsychological variables. We observed in 60% of the myasthenics, low grade central type of sleep apneas and hypopneas with resulting oxygen desaturations, occasionally occurring during REM-sleep without influence on sleep profile and vigilance but resulting in significant memory impairment. The only found risk factor for the development of sleep apneas was age.
