Chung-Yao Hsu

Rapid-eye-movement sleep behavior disorder secondary to acute aseptic limbic encephalitis

Rapid-eye-movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by complex motor activity associated with dreaming during REM sleep. RBD may be idiopathic or associated with various neurological diseases involving the brainstem. The association of RBD and limbic system impairment was unclear. We report a 46-year-old man with acute aseptic limbic encephalitis in association with RBD. The patient presented with subacute onset of anterograde/retrograde amnesia and persistent fever. Abnormal nocturnal behavior during sleep consisted of waving hands to fight and kicking legs. Brain magnetic resonance imaging showed damage on the bilateral unci and medial temporal lobes. Cerebrospinal fluid analysis indicated aseptic encephalitis. A polysomnography revealed augmented phasic activity in the submental and bilateral tibialis anterior muscles during REM sleep. Our finding suggests that limbic system impairment may lead to the occurrence of RBD.

The rapid-eye-movement sleep behavior disorder in Chinese-Taiwanese patients

Aims:  While the features of rapid‐eye‐movement sleep behavior disorder (RBD) have been reported in Caucasian patients, the characteristics of Chinese‐Taiwanese patients with RBD have never been examined.

Nurses working on fast rotating shifts overestimate cognitive function and the capacity of maintaining wakefulness during the daytime after a rotating shift.

OBJECTIVES The objective of our study was to explore changes in cognitive functions, sleep propensity, and sleep-related hormones (growth hormone [GH], cortisol, prolactin [PRL], thyrotropin [TSH]) in the daytime of nurses working on fast rotating shifts. METHODS Twenty nurses who worked two consecutive night shifts and 23 off-duty nurses were recruited from an acute psychiatric ward. The maintenance of wakefulness test (MWT), Stanford sleepiness scale (SSS), visual attention tasks, Wisconsin card sorting test (WCST), multiple sleep latency test (MSLT), and measuring hormones were administered four times throughout the daytime at 2-hour intervals. RESULTS The subjects in the off-duty group were more able to maintain wakefulness than those in the night-shift group; however, there were no differences in self-reported total sleep time or sleep latency on the MSLT and SSS scores between the two groups. The subjects in the night-shift group had poorer performances on visual attentive tasks and higher levels of TSH than those in the off-duty group, and this resulted in a lack of a learning effect on the tasks that required a high attentive load. CONCLUSIONS Nurses working on fast rotating shifts overestimate the cognitive functions and capacity of maintaining wakefulness following daytime sleep restriction. Attention performance depended on the attentive load requirement and was possibly related to TSH level.

Did a brief nap break have positive benefits on information processing among nurses working on the first 8-h night shift?

Shift workers frequently experience acute sleep deprivation on first night shift. This study compared the efficacy of 30-min nap (between 2 and 3 a.m.) on the visual attention ability of the nurses working at first 8-h night shift at the time of maximum fatigue (between 3 and 4 a.m.). In addition, we measured cognitive function (between 9 and 10 a.m.) in nurses working on daytime shift, which we defined as baseline wakefulness. The results showed that working on the night shift groups was associated with sleep loss, leading to a decrease in visual attention performance compared to the daytime shift group. There was no statistically significant difference in the visual attention performance between those taking and not taking a nap during the night shift, however the effect size was medium in the information process. It was still needed increase sample size to draw the conclusion regarding a 30-min nap break have positive benefits on perceptual speed during the first night shift.

Rotating night shifts too quickly may cause anxiety and decreased attentional performance, and impact prolactin levels during the subsequent day: a case control study

BackgroundWe investigated circadian changes and effects on mood, sleep-related hormones and cognitive performance when nurses worked consecutive night shifts in a rapidly rotating shift system. Daytime cognitive function, sleep propensity and sleep-related hormones (growth hormone, cortisol, prolactin, thyrotropin) were compared after participants worked two and four consecutive night shifts.MethodsTwenty-three off-duty nurses, 20 nurses working two consecutive night shifts and 16 nurses working four consecutive night shifts were enrolled. All participants completed the Maintenance of Wakefulness Test, State-Trait Anxiety Inventory, Stanford Sleepiness Scale, visual attention tasks (VAT), Wisconsin Card Sorting Test, and modified Multiple Sleep Latency Test. Hormone levels were also measured four times throughout the day, at 2-h intervals.ResultsDuring the day, the participants in the night shift groups were less able to maintain wakefulness, had poor performance on VAT, and higher thyrotropin levels than did those in the off-duty group. Participants who worked two night shifts were better able to maintain wakefulness, had higher anxiety scale scores, poorer initial performance and lack of learning effect on VAT, and higher prolactin levels compared with those who worked four night shifts. There were no differences in cortisol levels between the two- and four- shift groups.ConclusionsRotating night shifts too quickly may cause anxiety and decreased attentional performance, and may impact daytime prolactin levels after night shifts. It is possible that the two-shift group had a higher cortisol level than did the four-shift group, which would be consistent with the group’s higher state anxiety scores. The negative findings may be due to the small sample size. Further studies on the effects of consecutive night shifts on mood and cortisol levels during the daytime after sleep restriction would be valuable.

Basal sympathetic predominance in periodic limb movements in sleep with obstructive sleep apnea

Because the impact of periodic limb movements in sleep (PLMS) is controversial, no consensus has been reached on the therapeutic strategy for PLMS in obstructive sleep apnea (OSA). To verify the hypothesis that PLMS is related to a negative impact on the cardiovascular system in OSA patients, this study investigated the basal autonomic regulation by heart rate variability (HRV) analysis. Sixty patients with mild‐to‐moderate OSA who underwent polysomnography (PSG) and completed sleep questionnaires were analysed retrospectively and divided into the PLMS group (n = 30) and the non‐PLMS group (n = 30). Epochs without any sleep events or continuous effects were evaluated using HRV analysis. No significant difference was observed in the demographic data, PSG parameters or sleep questionnaires between the PLMS and non‐PLMS groups, except for age. Patients in the PLMS group had significantly lower normalized high frequency (n‐HF), high frequency (HF), square root of the mean of the sum of the squares of difference between adjacent NN intervals (RMSSD) and standard deviation of all normal to normal intervals index (SDNN‐I), but had a higher normalized low frequency (n‐LF) and LF/HF ratio. There was no significant difference in the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index, the Short‐Form 36 and the Hospital Anxiety and Depression Scale between the two groups. After adjustment for confounding variables, PLMS remained an independent predictor of n‐LF (β = 0.0901, P = 0.0081), LF/HF ratio (β = 0.5351, P = 0.0361), RMSSD (β = −20.1620, P = 0.0455) and n‐HF (β = −0.0886, P = 0.0134). In conclusion, PLMS is related independently to basal sympathetic predominance and has a potentially negative impact on the cardiovascular system of OSA patients.

Isolated aphasic status epilepticus as initial presentation of nonketotic hyperglycemia.

Diagnosis of aphasic status epilepticus is sometimes not easy because of its rarity and electroclinical dissociation. Although most cases are associated with organic brain lesions, nonketotic hyperglycemia (NKH)–related aphasic status epilepticus is rare, especially if it is isolated (without other clinical seizure activity). On the other hand, unlike other metabolic disorders, or hypoglycemia-related generalized seizures, focal motor seizure and epilepsia partialis continua can occur in 25% of NKH, with seizures being the initial manifestation in up to 50% of patients. However, the presentation of epileptic aphasia is rare in NKH patients. We report a rare case of NKH presenting initially as persistent and isolated aphasic status epilepticus. Brain magnetic resonance imaging did not reveal any focal lesion, but ictal electroencephalography (EEG) disclosed left frontotemporal continuous theta to delta waves, intermingled with epileptiform discharges. Correcting the hyperglycemia failed to improve the language disorder, and the seizure was controlled only by the addition of carbamazepine. Patients with NKH may initially present with isolated aphasic status epilepticus. Unlike stroke-related aphasia, accurate diagnosis is difficult if based solely on neurologic examination and brain neuroimaging. Use of EEG and blood sugar determination should be helpful in this special condition.

Acute confusion in headache with neurologic deficits and cerebrospinal fluid lymphocytosis syndrome

Abrupt headaches with focal neurologic deficits usually indicate medical emergencies that require advanced investigations and prompt treatment. The distinct syndrome of “headache with neurologic deficits and cerebrospinal fluid lymphocytosis” (HaNDL) is infrequent and considered a benign, self-limited disorder. We illustrated a 29-year-old man with HaNDL atypically presenting as episodic altered consciousness rather than sensorimotor prodromes. The diagnosis was made carefully by exclusion of other likely entities. It is important for clinical physicians to differentiate HaNDL from other potentially fatal.

Erectile Dysfunction in Patients with Sleep Apnea – A Nationwide Population-Based Study

Increased incidence of erectile dysfunction (ED) has been reported among patients with sleep apnea (SA). However, this association has not been confirmed in a large-scale study. We therefore performed a population-based cohort study using Taiwan National Health Insurance (NHI) database to investigate the association of SA and ED. From the database of one million representative subjects randomly sampled from individuals enrolled in the NHI system in 2010, we identified adult patients having SA and excluded those having a diagnosis of ED prior to SA. From these suspected SA patients, those having SA diagnosis after polysomnography were defined as probable SA patients. The dates of their first SA diagnosis were defined as their index dates. Each SA patient was matched to 30 randomly-selected, age-matched control subjects without any SA diagnosis. The control subjects were assigned index dates as their corresponding SA patients, and were ensured having no ED diagnosis prior to their index dates. Totally, 4,835 male patients with suspected SA (including 1,946 probable SA patients) were matched to 145,050 control subjects (including 58,380 subjects matched to probable SA patients). The incidence rate of ED was significantly higher in probable SA patients as compared with the corresponding control subjects (5.7 vs. 2.3 per 1000 patient-year; adjusted incidence rate ratio = 2.0 [95% CI: 1.8-2.2], p<0.0001). The cumulative incidence was also significantly higher in the probable SA patients (p<0.0001). In multivariable Cox regression analysis, probable SA remained a significant risk factor for the development of ED after adjusting for age, residency, income level and comorbidities (hazard ratio = 2.0 [95%CI: 1.5-2.7], p<0.0001). In line with previous studies, this population-based large-scale study confirmed an increased ED incidence in SA patients in Chinese population. Physicians need to pay attention to the possible underlying SA while treating ED patients.

Parallel improvement of cognitive functions and P300 latency following donepezil treatment in patients with Alzheimer's disease: a case-control study.

Purpose: To evaluate the effect of donepezil, one of the cholinesterase inhibitors, on P300 measurements in patients with Alzheimers disease (AD) and investigate the relationship between the subfactors of cognitive performance and P300 components. Methods: One hundred outpatients with AD were evaluated for cognitive function (cognitive ability screening instrument) and event-related potentials before and after 22 to 23 weeks of treatment with donepezil (5 mg/day). Twenty age-matched normal control subjects were recruited. Results: The patients with AD showed prolonged P300 and N200 latency, no significant differences in N100 and P200 components, and poor performance in neuropsychological assessments compared with control subjects at baseline. After donepezil treatment, the patients with AD had reduction in P300 latency at Pz lead, which was associated with a parallel improvement in cognitive function in terms of remote memory, recent memory, visual instruction, and orientation. The pre–post treatment difference of P300 latency significantly correlated with the cognitive ability screening instrument score difference and recent memory score difference, respectively. Conclusions: The patients with AD still had intact early sensory processing but impaired higher-level cognitive processes that could influence behavior deviation. The donepezil treatment, which enhances higher-level cognitive processing time, revealed that P300 latency decreases as cognitive capability increases, especially improved in recent memory.