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Beth A Malow

Publications and source records attributed to Beth A Malow.

At least 19 recordsLinked to original sources
PubMed2023

Next-generation phenotyping: introducing phecodeX for enhanced discovery research in medical phenomics.

MOTIVATION: Phecodes are widely used and easily adapted phenotypes based on International Classification of Diseases codes. The current version of phecodes (v1.2) was designed primarily to study common/complex diseases diagnosed in adults; however, there are numerous limitations in the codes and their structure. RESULTS: Here, we present phecodeX, an expanded version of phecodes with a revised structure and 1,761 new codes. PhecodeX adds granularity to phenotypes in key disease domains that are under-represented in the current phecode structure-including infectious disease, pregnancy, congenital anomalies, and neonatology-and is a more robust representation of the medical phenome for global use in discovery research. AVAILABILITY AND IMPLEMENTATION: phecodeX is available at https://github.com/PheWAS/phecodeX.

Phenomics↗
PubMed2006

PHOX2B mutation-confirmed congenital central hypoventilation syndrome: presentation in adulthood.

Congenital central hypoventilation syndrome (CCHS) typically presents in the newborn period. A case series of five adults is presented, each heterozygous for a documented polyalanine expansion mutation in the PHOX2B gene and evidence of nocturnal alveolar hypoventilation. All cases had symptoms in childhood, but survived to adulthood without ventilatory support. After identification of physiologic compromise, artificial ventilation was initiated. These adults have the mildest of the CCHS-related PHOX2B polyalanine expansion mutations, coding for only five extra alanines; three of the adults have affected offspring. Report of these cases should lead to a more rapid identification of CCHS presenting in adulthood.

Adult↗
PubMed2006

Impact of treating sleep apnea in a child with autism spectrum disorder.

Sleep disorders can affect daytime functioning in a variety of neurologic conditions, including autism spectrum disorder. This report describes improvements in sleep, social communication, attention, repetitive behaviors, and hypersensitivity after adenotonsillectomy for obstructive sleep apnea in a 5-year-old female with an autism spectrum disorder. Improvements were documented via pre- and postsurgical measures of parent report, polysomnography, validated sleep and behavior scales, and the Autism Diagnostic Observation Schedule. Identification and treatment of sleep disorders, including obstructive sleep apnea, may improve daytime behavior in children with autism spectrum disorders.

Adenoidectomy↗
PubMed2006

Partial epilepsy presenting as apneic seizures without posturing.

Apnea is a symptom present in many conditions. During the neonatal period, apnea has been associated with epileptiform activity in the absence of posturing. However, the occurrence of apneic seizures without posturing beyond the neonatal period is an uncommon presentation for partial epilepsy. The aim of this case report is to present a rarely documented cause of apnea and desaturation in an otherwise healthy 24-month-old child. Further investigations revealed that the etiology of the spells was partial seizures originating in the right anterior midtemporal region. Polysomnography with extended electroencephalography and video is the gold standard tool to evaluate patients with apnea due to suspected seizures.

Apnea↗
PubMed2005

Sleep and epilepsy.

This article examines the relationship between sleep and epilepsy, an association that has been recognized since antiquity. The mechanisms whereby sleep facilitates seizures are under investigation, although the synchronizing role of thalamocortic networks seems contributory. Recognition of the variety of generalized and partial epileptic syndromes associated with sleep, familiarity with the differential diagnosis of nocturnal spells, and awareness of the role that antiepileptic drugs and sleep disorders may play in epilepsy are helpful in evaluating patients presenting with behavioral and motor disturbances of sleep.

Automatism↗
PubMed2005

Analysis of the first night effect and sleep parameters in medically refractory epilepsy patients.

OBJECTIVES: To assess the first night effect (FNE) and compare sleep stage proportions to normative values in a sample of medically refractory epilepsy patients. PATIENTS AND METHODS: Sleep parameters of 53 epilepsy patients, ages (18-56, mean: 34+/-12, 25 females 28 men), who underwent two consecutive nights of polysomnography (PSG) were compared. Non-rapid eye movement (NREM) stage 3 and NREM stage 4 were combined as slow wave sleep (SWS). Sleep efficiency, sleep latency, rapid eye movement (REM) latency, number of stage shifts, total minutes and proportion of total sleep time for stage 1, stage 2, SWS, and REM sleep were compared between the 2 nights. RESULTS: SWS was the only parameter that differed between nights 1 and 2 for both total minutes (P=0.02) and proportion of total sleep time (P=0.01), although the means for both nights were within the normative range. Comparing sleep proportions to normative values indicates that our patients had increased NREM stage 1 and decreased REM sleep. CONCLUSIONS: We observed a minimal FNE in this sample of epilepsy patients manifested by reduced SWS. Multiple PSGs to accommodate the FNE may not be necessary in this population.

Adolescent↗
PubMed2004

Sleep disorders, epilepsy, and autism.

The purpose of this review article is to describe the clinical data linking autism with sleep and epilepsy and to discuss the impact of treating sleep disorders in children with autism either with or without coexisting epileptic seizures. Studies are presented to support the view that sleep is abnormal in individuals with autistic spectrum disorders. Epilepsy and sleep have reciprocal relationships, with sleep facilitating seizures and seizures adversely affecting sleep architecture. The hypothesis put forth is that identifying and treating sleep disorders, which are potentially caused by or contributed to by autism, may impact favorably on seizure control and on daytime behavior. The article concludes with some practical suggestions for the evaluation and treatment of sleep disorders in this population of children with autism.

Antioxidants↗
PubMed2004

Subclinical rhythmic electrographic discharge of adults (SREDA) in REM sleep.

We describe the first reported case of subclinical rhythmic electrographic discharge of adults (SREDA) during rapid eye movement (REM) sleep. This 48-year-old man, with a history of witnessed apneic spells, was sent for a baseline polysomnogram. Besides demonstrating obstructive sleep apnea, his study showed the occurrence of paroxysmal delta waves evolving into a theta frequency during REM sleep. A repeat polysomnogram with 16-channel electroencephalography confirmed SREDA in the bilateral temporal/parietal regions during REM sleep. This uncommon paroxysmal electrographic pattern should not be mistaken for seizure activity and is now recognized to occur in all stages of sleep, including REM.

Adult↗
PubMed2004

Blockade of endogenous growth hormone-releasing hormone receptors dissociates nocturnal growth hormone secretion and slow-wave sleep.

OBJECTIVES: A temporal association between non-rapid eye movement (NREM) sleep stages 3 and 4 and nocturnal augmentation of GH release was found long ago, yet the precise mechanism for this association has not been identified. It has been shown, however that pulsatile GHRH administration increases both slow-wave sleep (SWS) and GH. Based on these data, a role for GHRH as an inducer of SWS was proposed. To test this hypothesis, we have performed the corollary experiment whereby the action of endogenous GHRH has been antagonized. DESIGN: Healthy men (20-33 years old) had an infusion of GHRH antagonist ((N-Ac-Tyr(1), D-Arg(2)) GHRH-29 (NH(2))) or saline for a 12-h period, between 2100 and 0900 h. An i.v. bolus of GHRH was given at 0700 h and GH samples were drawn from 0700 to 0900 h to document the efficacy of GH suppression by the GHRH antagonist. METHODS: A limited montage sleep study was recorded from 2300 to 0700 h during each admission. Plasma GH concentrations were analyzed by the use of a sensitive chemiluminometric assay. RESULTS: Effectiveness of the GHRH antagonist was validated in all subjects by demonstrating 93+/-1.8% (P=0.012) suppression of GH response to a GHRH bolus. Polysomnography demonstrated that the percentage of SWS was not different when saline and GHRH antagonist nights were compared (P=0.607); other quantifiable sleep parameters were also unchanged. CONCLUSIONS: We conclude that endogenous GHRH is indispensable for the nocturnal augmentation of GH secretion, but that it is unlikely to participate in the genesis of SWS.

Adult↗
PubMed2003

Identification and treatment of obstructive sleep apnea in adults and children with epilepsy: a prospective pilot study.

OBJECTIVE: To determine the effect of treating obstructive sleep apnea (OSA) on seizure frequency in adults and children with epilepsy in a prospective study. Several case series documented an improvement in seizure control with treatment of coexisting OSA, but published series did not sample a clinic population, were not prospective in design, and did not account for concurrent changes in antiepileptic drug (AED) doses or levels. PATIENTS AND METHODS: Adult patients and the parents of pediatric patients seen in the University of Michigan Epilepsy and Pediatric Neurology Clinics were given validated questionnaires. Thirteen adults (aged 20-56) and 5 children (aged 14-17) were selected for polysomnography (PSG) based on frequency of seizures and risk for OSA. Seizure frequency was compared during 8-week baseline and treatment phases and AED levels were done to document stability in medication levels. RESULTS: Six of 13 adults and 3 of 5 children met PSG criteria for OSA. Three adults and 1 child were treated with continuous positive airway pressure (CPAP), were tolerant of the device, and had no change in AED doses; all four had at least a 45% reduction in seizure frequency during CPAP treatment. One adult was treated with an oral appliance with a reduction in nocturnal seizures only, and 2 adults and 2 children were intolerant of CPAP. CONCLUSIONS: Treatment of OSA in patients with epilepsy may improve seizure control and a large randomized placebo-controlled trial appear warranted.

Adolescent↗
PubMed2003

Obstructive sleep apnea in epilepsy patients: the Sleep Apnea scale of the Sleep Disorders Questionnaire (SA-SDQ) is a useful screening instrument for obstructive sleep apnea in a disease-specific population.

OBJECTIVE: To determine useful cutoffs on the Sleep Apnea scale of the Sleep Disorders Questionnaire (SA-SDQ) in an epilepsy population. BACKGROUND: Epilepsy and obstructive sleep apnea (OSA) frequently coexist, and treating OSA in epilepsy patients may reduce seizure frequency and improve daytime sleepiness. The SA-SDQ, a 12-item validated measure of sleep-related breathing disorders, may be a useful tool to screen epilepsy patients for OSA, although appropriate cutoff points have not been established in this population. Previously suggested SA-SDQ cutoff points for OSA in a non-epilepsy population were 32 for women and 36 for men. PATIENTS AND METHODS: One hundred twenty-five subjects with epilepsy undergoing polysomnography completed a survey about their sleep, including the 12-item SA-SDQ scale. Receiver-operating characteristics curves were constructed to determine optimal sensitivity and specificity. RESULTS: Sixty-nine of the 125 subjects (45%) had apnea-hypopnea indices greater than five, indicating OSA. The area under the curve was 0.744 for men and 0.788 for women. For men, an SA-SDQ score of 29 provided a sensitivity of 75% and a specificity of 65%. For women, an SA-SDQ score of 26 provided a sensitivity of 80% and a specificity of 67%. CONCLUSIONS: The SA-SDQ is a useful screening instrument for OSA in an epilepsy population. Our results indicate that the previously suggested cutoffs for OSA (36 for men and 32 for women) may be too high for this specific population. We suggest screening cutoffs of 29 for men and 26 for women.

Disorders of Excessive Somnolence↗
PubMed2003

Sleep disorders: a sometimes forgotten cause of nonepileptic spells.

We present a patient with spells of loss of awareness in which the initial diagnostic consideration was partial epilepsy. The patient underwent video-EEG long-term monitoring which raised suspicion of nonepileptic events, but could not exclude simple partial seizures. A failed therapeutic trial with antiepileptic medication and adverse events prompted reevaluation of the case. Sleep studies, including polysomnography and multiple sleep latency testing (MSLT), confirmed a sleep disorder, i.e., narcolepsy, which responded to specific therapy with resolution of the spells.

Adult↗
PubMed2003

Approaches to staging sleep in polysomnographic studies with epileptic activity.

BACKGROUND: The Standardized Sleep Manual of Rechtschaffen and Kales is well established and reliable in scoring the majority of polysomnograms (PSGs) encountered in clinical practice. In patients with epilepsy, however, abnormal brain activity may confound the interpretation of sleep waveforms. Our goal is to identify features that are problematic in analyzing sleep stages in patients with epilepsy and to offer approaches to score these PSGs. METHODS: Ninety eight PSGs from 43 patients with epilepsy were scored using Rechtschaffen and Kales guidelines. Features interfering with sleep staging were noted. RESULTS: In scoring polysomnograms (PSGs) of patients with epilepsy we noted epileptic seizures, interictal epileptiform discharges (IEDs) and abnormal EEG background to be features of epilepsy that compromised sleep scoring. Overall, 48% of the studies in our sample contained one or more of these epileptic features to the extent that sleep scoring by standard criteria was compromised. Approaches for staging sleep in the setting of these abnormalities are outlined. CONCLUSIONS: The Rechtschaffen and Kales method of sleep scoring is useful in staging the majority of PSGs of patients with epilepsy. However, we advocate some modifications because the abnormal electrical activity of epilepsy may interfere with accurate scoring of sleep waveforms. These approaches to scoring PSGs of patients with epilepsy will require empirical testing.

Electroencephalography↗
PubMed2003

Effects of vagus nerve stimulation on sleep-related breathing in epilepsy patients.

PURPOSE: To describe the effects of vagus nerve stimulation (VNS) on sleep-related breathing in a sample of 16 epilepsy patients. METHODS: Sixteen adults with medically refractory epilepsy (nine men, seven women, ages 21-58 years) underwent baseline polysomnograms (PSGs). Three months after VNS therapy was initiated, PSGs were repeated. In addition, patient 7 had a study with esophageal pressure monitoring, and patient 1 had a continuous positive airway pressure (CPAP) trial. RESULTS: Baseline PSGs: One of 16 patients had an apnea-hypopnea index (AHI) >5 (6.8). Treatment PSGs: Five of 16 patients had treatment AHIs >5. Respiratory events were more frequent during periods with VNS activation (on-time) than without VNS activation (off-time; p = 0.016). Follow-up studies: Esophageal pressure monitoring in patient 7 showed crescendos in esophageal pressure during VNS activation, supporting an obstructive pattern. The CPAP trial of patient 1 showed that all respiratory events were associated with VNS stimulation at low CPAP levels. They were resolved at higher CPAP levels. CONCLUSIONS: Treatment with VNS affects respiration during sleep and should be used with care, particularly in patients with preexisting obstructive sleep apnea. The AHI after VNS treatment remained <5 in the majority of patients and was only mildly elevated (<12) in five patients. In one patient, CPAP resolved VNS-related respiratory events.

Adult↗
PubMed2003

Long-term outcome of nonsurgical candidates with medically refractory localization-related epilepsy.

PURPOSE: Epilepsy surgery can result in complete seizure remission rates of upto 80% in patients with mesial temporal sclerosis and unilateral seizures. The seizure-free rate after surgery for patients with extratemporal nonlesional epilepsy has ranged between 30% and 40%. Some patients with medically refractory localization-related epilepsy cannot be offered surgical resection because of inadequate localization of the epileptogenic zone, documentation of bilateral ictal onsets, or functionally important areas of cortex that prohibit resection. The short-term rate of complete remission with medications in temporal lobe epilepsy is poor. Less is known about remission rates in patients who are not surgical candidates. In this study, we evaluated the outcome of medical treatment in patients with medically refractory partial epilepsy who were evaluated for possible epilepsy surgery but deemed to be inadequate surgical candidates. METHODS: A retrospective chart review and telephone survey with a self-rating questionnaire were completed for all patients who underwent epilepsy surgery evaluation but were not ultimately offered surgical treatment at the University of Michigan from 1990 through 1998. We assessed changes in seizure frequency and type, imaging characteristics, ictal recordings, interim medication history, and subjective changes in quality of life. RESULTS: Thirty-four subjects were available for follow-up study, at an average of >4 years after surgical evaluation. A significant reduction in seizure frequency was noted at the time of follow-up compared with that at the time of surgical evaluation. Of patients, 21% achieved seizure remission and remained seizure free for an average of 2.5 years. Four of the seven seizure-free patients attributed their remission to new antiepileptic drugs (AEDs). On a global self-rating item, 15 of 34, or 44%, felt more or much more satisfied with their lives, and 41% felt their quality of life was stable. CONCLUSIONS: A surprisingly large number of patients we surveyed, with refractory partial epilepsy not eligible for surgical management, reported reduced seizure frequency at follow-up, and 21% were seizure free. Our findings suggest that the long-term prognosis in patients with refractory partial epilepsy who are not surgical candidates may be more positive than might be generally expected.

Adult↗
PubMed2002

Interictal epileptiform discharges do not change before seizures during sleep.

PURPOSE: Whether interictal epileptiform discharges (IEDs) increase, decrease, or are unchanged before epileptic seizures has implications for the pathophysiology of epilepsy. Prior studies relating IEDs and seizures have not demonstrated a change in IEDs before seizures. However, they have not controlled for changes in the depth of sleep. Our objective was to test the hypothesis that IEDs are related to seizures during sleep while adjusting for log delta power (LDP), a continuous measure of sleep depth. METHODS: Twenty-two seizures during sleep were identified in 16 subjects with epilepsy admitted for presurgical monitoring. The IEDs that occurred in the hour of sleep before each seizure were used to test the relation between IEDs and seizure occurrence. Sleep depth was measured by LDP (quantity of 1- to 4-Hz activity in 30-s epochs), and records were scored visually for sleep staging and for IEDs. Multivariate logistic regression analyses were applied. RESULTS: Adjusting for LDP, number of seizures before the current seizure, quartile of the night, and total number of IEDs that occurred during the night, IED did not increase or decrease before seizures (p > 0.1). The rate of IEDs increased directly with LDP (p=0.0001), as shown in prior work. CONCLUSIONS: IEDs are not activated or suppressed before seizures during sleep, suggesting that different pathophysiologic processes underlie these two phenomena. These results corroborate prior studies, while providing a more advanced analysis by adjusting for sleep depth and applying multivariate logistic regression analyses.

Adult↗
PubMed2002

Paroxysmal events in sleep.

This review describes the wide spectrum of episodic phenomena that can occur during sleep. These phenomena include arousal disorders of nonrapid eye movement (NREM) sleep, rapid eye movement (REM) sleep behavior disorder, movement disorders, psychiatric disorders, and epileptic seizures. Each of these entities is discussed in detail, focusing on their clinical manifestations, diagnosis, and treatment. Essential historic elements that distinguish these events and the role of video-EEG-polysomnography in their differential diagnosis are emphasized.

Diagnosis, Differential↗