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M J Thorpy

Publications and source records attributed to M J Thorpy.

At least 19 recordsLinked to original sources
PubMed1992

Short-term triazolam use improves nocturnal sleep of narcoleptics.

This study was undertaken to determine whether the use of triazolam by narcoleptic patients leads to improvement of nighttime sleep or excessive sleepiness. Ten narcoleptic patients, 5 males and 5 females, with complaints of sleep disturbance and aged between 18 and 60 years, were assigned to a single-blind within-subject crossover-designed study comparing placebo with 0.25 mg triazolam. All subjects completed sleep questionnaires and underwent 6 nights of polysomnographic testing. Following an adaptation night, subjects received either triazolam or placebo for 2 nights. Objective tests of sleepiness (multiple sleep latency testing/maintenance of wakefulness test) were performed. Sleep efficiency and overall sleep quality were improved on all triazolam nights. Daytime excessive sleepiness was not reduced objectively after triazolam. This study demonstrates that the short-term use of triazolam improves nocturnal sleep quality in narcoleptics. Studies of long-term administration of triazolam are required to determine if the improvement of nocturnal sleep is maintained.

Adult↗
PubMed1992

T-sleep: an improved method for scoring breathing-disordered sleep.

We developed a new method to score sleep fragmented by respiratory events that we call the T-sleep (transitional sleep scoring) method. Five control polysomnograms from subjects without sleep-related breathing abnormalities were scored by the Rechtschaffen and Kales (R&K) method, and 10 polysomnograms from patients with severe obstructive sleep apnea were scored by both the R&K and the T-sleep method. Comparative analyses were performed on sleep variables of the control and apnea polysomnograms, and interscorer correlations were assessed for sleep and apnea variables. The interscorer correlations were high for both R&K control scoring and for apnea recordings scored by the T-sleep method. The number of sleep stage events documented for the 10 apnea recordings was significantly less for the T-sleep method than the R&K method (36, SD 17.0 vs. 332, SD 144.0; p = 0.0002). The T-sleep method was shown to be an effective, accurate and quick method for scoring sleep in patients with sleep-related breathing disorders.

Adult↗
PubMed1990

The use of sleep studies in neurologic practice.

Polysomnographic studies have been shown to be useful in the diagnosis of many sleep disorders, particularly those associated with impaired respiration during sleep or impairment of daytime alertness. As with any test, unless it is performed under ideal conditions, the amount of information obtained may be limited. Because of the interaction between nighttime sleep and daytime alertness, disorders associated with impaired alertness usually require at least 24-hour assessment. The polysomnogram and MSLT, although detailed and time consuming, are essential for the accurate diagnosis of many sleep disorders. If a primary sleep disorder is suspected, polysomnographic testing, particularly early in the patient's evaluation, may obviate unnecessary neurologic and medical tests, which yield little information in the assessment of disorders of sleep and wakefulness.

Circadian Rhythm↗
PubMed1990

Effects of otolithic vestibular stimulation on sleep.

This study evaluated the effects of otolithic vestibular stimulation in the form of a linearly accelerated parallel swing on nighttime sleep parameters and daytime sleep tendency in eight normal subjects. The protocol consisted of one adaptation night following by two motion nights, one adaptation night followed by two stationary nights, and two Multiple Sleep Latency Tests (MSLT), one motion and one stationary. On the motion nights, there was a decrease in stage 2 percentage as well as a facilitative effect on sleep latency on the last night. In addition, an increase in the number of rapid eye movements (REMs) per night was found without a significant alteration of REM sleep amount or latency. No significant differences were found between the motion and stationary MSLT days.

Adaptation, Physiological↗
PubMed1990

Classification of sleep disorders.

This review discusses recent developments in classifying the sleep disorders. Several classification systems are presented, and the Diagnostic Classification of the Sleep and Arousal Disorders (DCSAD), published by the Association of Sleep Disorders Centers in 1979, is used as the basis for reviewing their differences. The four main sections of the DCSAD are presented: the disorders of initiating and maintaining sleep, the disorders of excessive somnolence, the sleep-wake schedule disorders, and the dysfunctions associated with sleep, sleep stages, or partial arousals. Disorders discovered since the publication of the DCSAD are mentioned along with the new nomenclature of the International Classification of Sleep Disorders, due to be published in 1990. References are given to the original clinical descriptions and nomenclature.

Disorders of Excessive Somnolence↗
PubMed1988

Delayed sleep phase syndrome in adolescents.

The delayed sleep phase syndrome is characterized by difficulty in falling asleep at a socially acceptable time of night and an inability to be easily aroused in the morning. Most commonly encountered in adolescents, this condition can produce daytime sleepiness and poor school performance, and it can lead to behavioral problems. The clinical features of the syndrome are described in 22 adolescents. Nine subjects participated in a protocol of polysomnographic recordings to simulate habitual "weekday" and "weekend" sleep patterns. There was a significant increase in total sleep time (p less than 0.005) and REM sleep (p less than 0.001) during the "weekend" sleep period. A multiple sleep latency test was performed between the two nights to assess daytime sleep tendency. Daytime sleepiness was maximal in the morning, with a tendency for greater alertness as the day progressed. The reduced amount of REM sleep during the "weekdays" plus the tendency for sleepiness in the mornings may contribute to the behavioral and educational difficulties seen in these patients. Recognition of this syndrome enables a specific sleep schedule change to be made that effectively treats the problem.

Adolescent↗
PubMed1988

Effect of growth hormone treatment on sleep EEGs in growth hormone-deficient children.

Total sleep time, sleep stages 1-4, REM, REM latency, and sleep efficiency were analyzed in seven children with growth hormone deficiency (GHD) before and after growth hormone (GH) therapy. Before GH therapy, GHD children spent 19.5% of their total sleep time in REM sleep, 9.7% in stage 1, 41.0% in stage 2, 10.0% in stage 3, and 19.7% in stage 4. GHD children had more stage 1 and 3 sleep and less REM as compared with age-matched normal children reported by Williams et al. After GH therapy was initiated, six of the seven patients had decreases in the duration of stage 3 sleep, with an average decrease of 21.8 min. The difference between stage 3 sleep before and during GH treatment was significant, with a p value of less than 0.025. When the results were expressed as the percentage of the total sleep period, the difference was also significant, (10.0 +/- 2.0 to 7.5 +/- 3.1%, mean +/- SD; p less than 0.05). No other sleep parameters were significantly affected by GH therapy. The changes observed in stage 3 sleep, non-REM sleep, and the lack of any other changes in sleep before and after GH therapy have not been described before in GH-deficient children. They differ from studies in normal humans and animals which showed that REM sleep increased with administration of growth hormone. These differences suggest that GH deficiency is associated with a specific sleep EEG anomaly that is corrected in part by GH therapy.

Child↗
PubMed1987

Reversibility of deficient sleep entrained growth hormone secretion in a boy with achondroplasia and obstructive sleep apnea.

Obstructive sleep apnea may lead to disordered sleep architecture and impair the physiologic slow wave sleep related growth hormone release. Obstructive sleep apnea occurs with craniofacial syndromes and in children with airway narrowing, pharyngeal hypoplasia, tonsillar adenoidal hypertrophy, micrognathia and achondroplasia. To examine the relationship between disordered sleep and growth hormone release we studied a 9 year old male with achondroplasia, growth failure (3 cm/year) and obstructive sleep apnea. Polysomnography data and a 20 min sampling for sleep entrained growth hormone showed before therapeutic tracheostomy numerous apneic episodes, absent slow wave sleep and abnormal low growth hormone secretion during sleep. Normalized slow wave sleep entrained growth hormone secretion after tracheostomy led to a sustained increase in growth rate. Normal growth rate (greater than 5 cm/year) continues 2 years after tracheostomy. We conclude that obstructive sleep apnea may impair sleep related growth hormone release. Obstructive sleep apnea may be a useful model for other diseases in which growth failure and sleep disturbances are linked.

Achondroplasia↗
PubMed1987

Parasomnias.

This article presents four examples of parasomnia activity. Sleepwalking, sleep terror, and rhythmic movement disorder all occur more commonly in children; however, they can persist into adulthood. REM behavior disorder frequently occurs in elderly patients with neurologic lesions. The sleep stage associations of the different disorders differ. Two of the disorders, sleepwalking and sleep terrors, have a clear association with stage 3/4 sleep, and REM behavior disorder occurs in REM sleep. Rhythmic movement disorder episodes can present solely in REM sleep but more typically occur in light non-REM sleep, and there are usually voluntary episodes during wakefulness.

Adolescent↗
PubMed1987

Treatment of chronic insomnia by restriction of time in bed.

A treatment of chronic insomnia is described that is based on the recognition that excessive time spent in bed is one of the important factors that perpetuates insomnia. Thirty-five patients, with a mean age of 46 years and a mean history of insomnia of 15.4 years, were treated initially by marked restriction of time available for sleep, followed by an extension of time in bed contingent upon improved sleep efficiency. At the end of the 8-week treatment program, patients reported an increase in total sleep time (p less than 0.05) as well as improvement in sleep latency, total wake time, sleep efficiency, and subjective assessment of their insomnia (all p less than 0.0001). Improvement remained significant for all sleep parameters at a mean of 36 weeks after treatment in 23 subjects participating in a follow-up assessment. Although compliance with the restricted schedule is difficult for some patients, sleep restriction therapy is an effective treatment for common forms of chronic insomnia.

Analysis of Variance↗
PubMed1986

Dynamics of REM sleep in narcolepsy.

The discovery of sleep onset REM periods (SOREMPs) in narcolepsy first suggested the important role of REM sleep in the disorder. We have conducted a series of studies exploring factors that affect the onset and termination of REM sleep in narcolepsy. Following a preliminary study of REM sleep deprivation, we compared the sleep onset response of narcoleptic and normal subjects to awakenings at REM sleep onsets and awakenings during NREM sleep. In addition, we have investigated the relationship of these awakenings to daytime sleepiness. We have demonstrated that an index of the REM sleep process predicts the sleepiness of both normal and narcoleptic subjects. The finding of increased frequency of SOREMPs following both REM and NREM sleep awakenings in the narcoleptic patient suggests that accelerated triggering and inertia of the REM sleep process are pathophysiological mechanisms of the disorder.

Activity Cycles↗
PubMed1985

Predictive value of Müller maneuver in selection of patients for uvulopalatopharyngoplasty.

Uvulopalatopharyngoplasty (UPPP) is an effective treatment for some patients with obstructive sleep apnea syndrome (OSAS). A major difficulty has been to select those patients who will have a good response to UPPP. Fiberoptic nasopharyngoscopy with Müller Maneuver (FNMM) was applied in preoperative evaluation of patients with OSAS to identify those in whom greatest pharyngeal collapse was in the region of the tonsillar fossae and soft palate. Those with pharyngeal changes on FNMM who were considered most likely to respond to surgery underwent UPPP. Comparison of pre and postoperative polysomnography reveals significant (p less than .001) improvement in indices of severity of OSAS The mean apnea index (apneas per hour) was diminished by 72%. Eighty-seven percent of patients had greater than 50% reduction in apnea index. Preoperative selection of OSAS patients by FNMM increases the likelihood of success of UPPP.

Adult↗
PubMed1985

Achondroplasia and obstructive sleep apnea: correction of apnea and abnormal sleep-entrained growth hormone release by tracheostomy.

Severe obstructive sleep apnea in a patient with achondroplasia syndrome was found to result in a definitive deficiency of overnight growth hormone secretion related to absence of slow-wave sleep. Resolution of the apnea by tracheostomy resulted in normalization of growth hormone release and normal growth rates postoperatively. Sleep-related growth hormone deficiency may contribute to the short stature so often seen in a variety of craniofacial syndromes. Furthermore, this short stature may be reversible.

Achondroplasia↗