Propriospinal myoclonus revisited: Clinical, neurophysiologic, and neuroradiologic findings.

OBJECTIVE: The literature on propriospinal myoclonus (PSM) is poor and there are no systematic reviews of the subject. We sought to clarify the spectrum of PSM. METHODS: We first prospectively investigated all patients seen in our movement disorders clinic with a firm diagnosis of PSM between 2002 and 2007. All had a standardized interview, detailed clinical examination, laboratory investigations, comprehensive neurophysiologic examination, and spinal cord MRI, including diffusion tensor imaging with fiber tracking (DTI-FT). We also collected drug responses. Finally, we conducted a systematic review of the literature. RESULTS: We enrolled 10 patients meeting the strict criteria for PSM, and also analyzed data on 50 patients from 26 previous reports. PSM occurred predominantly in male and middle-aged patients. The typical clinical picture consisted of myoclonic jerks consistently involving abdominal wall muscles, which worsen in the lying position. A premonitory sensation preceding the jerks and wake-sleep transition phase worsening were frequent. Most patients had a myoclonic generator at the thoracic level, with a myoclonus duration between 200 msec and 2 s. An underlying cause was infrequently found. DTI-FT detected cord abnormalities all of our patients. CONCLUSION: The clinico-physiologic spectrum of propriospinal myoclonus (PSM) is homogenous. Involvement of the abdominal wall muscles, worsening in the lying position, premonitory sensation, and wake-sleep transition phase worsening are helpful clinical clues. Diffusion tensor imaging with fiber tracking appears more sensitive than conventional MRI for detecting associated microstructural abnormalities of the spinal cord. Symptomatic treatment of PSM is not straightforward, and clonazepam is reported to be the most effective drug. Zonisamide may be an interesting option.

Sleep disorders and their impacts on healthy, dependent, and frail older adults.

BACKGROUND: Sleep disorders differ widely in the heterogeneous older adult population. Older adults can be classified into three groups based upon their overall level of disability: healthy, dependent, and frail. Frailty is an emerging concept that denotes older persons at increased risk for poor outcomes. OBJECTIVE: The aim of this consensus review is to describe the sleep disorders observed in healthy and dependent older adults and to discuss the potential sleep disorders associated with frailty as well as their potential consequences on this weakened population. METHODS: A review task force was created including neurologists, geriatricians, sleep specialists and geriatric psychiatrists to discuss age related sleep disorders depending on the three categories of older adults. All published studies on sleep in older adults on Ovid Medline were reviewed and 106 articles were selected for the purpose of this consensus. RESULTS: Many healthy older adults have complains about their sleep such as waking not rested and too early, trouble falling asleep, daytime napping, and multiple nocturnal awakenings. Sleep architecture is modified by age with an increased percentage of time spent in stage one and a decreased percentage spent in stages three and four. Insomnia is frequent and its mechanisms include painful medical conditions, psychological distress, loss of physical activity and iatrogenic influences. Treatments are also involved in older adults' somnolence. The prevalence of primary sleep disorders such as restless legs syndrome, periodic limb movements and sleep disordered breathing increases with age. Potential outcomes relevant to these sleep disorders in old age include mortality, cardiovascular and neurobehavioral co-morbidities. Sleep in dependent older adults such as patients with Alzheimer Disease (AD) is disturbed. The sleep patterns observed in these patients are often similar to those observed in non-demented elderly but alterations are more severe. Nocturnal sleep disruption and daytime sleepiness are the main problems. They are the results of Sleep/wake circadian rhythm disorders, environmental, psychological and iatrogenic factors. They are worsened by other sleep disorders such as sleep disordered breathing. Sleep in frail older adults per se has not yet been formally studied but four axes of investigation should be considered: i) sleep architecture abnormalities, ii) insomnia iii) restless legs syndrome (RLS), iv) sleep disordered breathing. CONCLUSION: Our knowledge in the field of sleep disorders in older adults has increased in recent years, yet some groups within this heterogeneous population, such as frail older adults, remain to be more thoroughly studied and characterized.

Vivid dreams, hallucinations, psychosis and REM sleep in Guillain-Barré syndrome.

We conducted a prospective controlled study of the clinical and biological determinants of the mental status abnormalities in 139 patients with Guillain-Barré syndrome (GBS) and 55 patients without GBS placed in the intensive care unit (ICU controls). There were mental status changes in 31% of GBS patients and in 16% of controls (odds ratio = 2.3; P = 0.04). In GBS patients, they included vivid dreams (19%), illusions (30%, including an illusory body tilt), hallucinations (60%, mainly visual) and delusions (70%, mostly paranoid). They appeared a median 9 days after disease onset (range 1-40 days, during the progression or the plateau of the disease), and lasted a median 8 days. Seven (16%) patients experienced the symptoms before their admission to the ICU. Hallucinations were frequently hypnagogic, occurring as soon as the patients closed their eyes. Autonomic dysfunction, assisted ventilation and high CSF protein levels were significant risk factors for abnormal mental status in GBS patients. CSF hypocretin-1 (a hypothalamic neuropeptide deficient in narcolepsy) levels, measured in 20 patients, were lower in GBS patients with hallucinations (555 +/- 132 pg/ml) than in those without (664 +/- 71 pg/ml, P = 0.03). Since the mental status abnormalities had dream-like aspects, we examined their association with rapid eye movement sleep (REM sleep) using continuous sleep monitoring in 13 GBS patients with (n = 7) and without (n = 6) hallucinations and 6 tetraplegic ICU controls without hallucinations. Although sleep was short and fragmented in all groups, REM sleep latency was shorter in GBS patients with hallucinations (56 +/- 115 min) than in GBS patients without hallucinations (153 +/- 130 min) and in controls (207 +/- 179 min, P < 0.05). In addition, sleep structure was highly abnormal in hallucinators, with sleep onset in REM sleep periods (83%), abnormal eye movements during non-REM sleep (57%), high percentages of REM sleep without atonia (92 +/- 22%), REM sleep behaviour disorders and autonomic dysfunction (100%), reminiscent of a status dissociatus. The sleep abnormalities, that were almost absent in non-hallucinated GBS patients, were not exclusively related to ICU conditions, since they also appeared out of ICU, and were reversible, disappearing when the mental status abnormalities vanished while the patients were still in ICU. In conclusion, the mental status abnormalities experienced by GBS patients are different from the ICU delirium, are strongly associated with autonomic dysfunction, severe forms of the disease and possibly with a transitory hypocretin-1 transmission decrease. Sleep studies suggest that mental status abnormalities are wakeful dreams caused by a sleep and dream-associated disorder (status dissociatus).