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M S Aldrich

Publications and source records attributed to M S Aldrich.

At least 37 records · Page 2Linked to original sources
PubMed1997

Compliance with stimulant medications in patients with narcolepsy.

The goals of this descriptive study were to determine what percentage of our treated narcoleptic subjects took their stimulant medications as prescribed and to examine the relationship between compliance and response to stimulant medications. Data obtained from a screening questionnaire, sleep diaries, and medical records showed that 22 of our 43 treated narcoleptic subjects reduced their dosage of stimulant medications or had not taken any stimulant medications during a 24-hour monitoring period during which they were expected to be on medication. Although we had expected better compliance among subjects who responded to stimulant medications (day-wake subjects), statistical testing revealed no significant differences between the two groups. Nor were there any significant differences in age, gender, or educational level when compliant and noncompliant subjects were compared. Only the type of drug prescribed (short versus long-acting stimulant) affected compliance; 39.4% of the subjects with prescriptions for dextroamphetamine or methylphenidate took the amount of medication prescribed compared to 87.5% of the subjects with prescriptions for pemoline.

Adolescent↗
PubMed1997

Compliance with nasal CPAP can be improved by simple interventions.

Effectiveness of continuous positive airway pressure (CPAP) as a treatment of obstructive sleep apnea can be limited by poor compliance, but little is known about how to improve compliance. We performed a randomized, controlled clinical trial among 33 subjects of two interventions to improve compliance. One group of subjects received weekly phone calls to uncover any problems and encourage use, another received written information about sleep apnea and the importance of regular CPAP use, and a third served as control subjects. We found that intervention improved CPAP compliance (p = 0.059) and that the effect was particularly strong when intervention occurred during the first month of CPAP treatment (p = 0.004). Although the sample size did not allow definitive investigation of other explanatory variables, subjects with lower levels of education or those with relatives who used CPAP may have benefited from intervention more than other subjects. We conclude that simple, inexpensive efforts to improve compliance with CPAP can be effective, especially when applied at the start of CPAP treatment, but optimal intervention may vary with certain patient characteristics.

Adult↗
PubMed1997

MRI findings in narcolepsy.

The neuropathology of narcolepsy is unknown. Recently, Plazzi et al. (1) reported magnetic resonance imaging (MRI) abnormalities in the pontine tegmentum of three patients with long-standing idiopathic narcolepsy. Considering the localization of the neuroradiological findings in the pontine reticular formation, where rapid eye movement (REM) sleep is generated, the authors suggested a causal relationship between narcolepsy and MRI abnormalities. Frey and Heiserman, however, found pontine MRI abnormalities in only two of 12 patients with narcolepsy both of whom had long-standing hypertension (2). Pullicino et al. noted similar pontine MRI abnormalities in patients with subcortical arteriosclerotic encephalopathy-like ischemic rarefaction of the pons (3). Thus, the changes noted by Plazzi et al. may have been caused by small-vessel disease rather than narcolepsy. To assess whether altered pontine MRI signals are a regular feature of idiopathic narcolepsy, we selected randomly from our database seven patients with narcolepsy with cataplexy. Of these seven, three agreed to have brain MRIs; their cases are described below. None had pontine MRI abnormalities.

Adult↗
PubMed1997

Sleep-disordered breathing in patients with acute supra- and infratentorial strokes. A prospective study of 39 patients.

BACKGROUND AND PURPOSE: Although recent studies suggest a high prevalence of obstructive sleep apnea (OSA) in patients with acute stroke, a systematic characterization of sleep-disordered breathing based on the severity and topography of stroke has not been performed. METHODS: We prospectively studied 39 noncomatose adult subjects (15 women, 24 men; mean age, 57 years) with a first acute stroke. Sleep history, cardiovascular risk factors, stroke severity as estimated by the Scandinavian Stroke Scale, and extent of stroke demonstrated on a computed tomographic or magnetic resonance imaging scan of the brain were assessed. Polysomnography was performed a mean of 10 days (range, 1 to 49 days) after stroke onset. Monitoring of breathing during wakefulness, non-rapid eye movement sleep, and rapid eye movement sleep included measurements of nasal/oral airflow, respiratory effort, and oxygen saturation. RESULTS: Breathing was abnormal during wakefulness in 7 (18%) subjects and during sleep in 26 (67%). Obstructive sleep apnea (apnea-hypopnea index > 10) was found in 14 subjects, Cheyne-Stokes-like breathing was observed in 4, and a combination of obstructive sleep apnea and Cheyne-Stokes-like breathing was observed in 7. Sustained tachypnea and ataxic breathing were rare. No significant differences were found in age, body mass index, history of snoring or hypersomnia, or stroke topography or severity between subjects with and without sleep-disordered breathing. Prevalence and severity of breathing disturbances were also similar between patients with supratentorial stroke (n = 28) and those with infratentorial (n = 11) stroke. CONCLUSIONS: Sleep-disordered breathing is frequent in patients with acute stroke, rarely has localizing value, and can also be found in patients with mild neurological deficits. Respiratory disturbances in stroke victims can be explained only in part by topography and extension of acute brain damage.

Acute Disease↗
PubMed1997

Effects of esophageal pressure monitoring on sleep architecture.

Esophageal pressure (Pes) monitoring can be performed during polysomnography with a thin, water-filled catheter connected to a transducer. The resulting quantitative assessment of respiratory effort aids in the diagnosis of sleep-related breathing disorders, but little is known about the potential effect of the procedure on sleep architecture. We monitored Pes during polysomnography in 155 patients and compared their sleep architecture with that of 155 matched patients who slept without esophageal catheters. Cases were matched for age, sex, and severity of respiratory disturbance during sleep. Esophageal manometry was associated with small but statistically significant (p < 0.05) decrements in total recording time, total sleep time, sleep efficiency, percent Stage 2 sleep, and percent rapid-eye-movement (REM) sleep, and with increases in latency to REM sleep, latency to persistent sleep, and percent Stage 3/4 sleep. The differences were of such small magnitude that their clinical significance is doubtful. The number of awakenings per hour of sleep, latency to sleep onset, and percent Stage 1 sleep were no different when esophageal manometry was used. We conclude that the effects of monitoring Pes on sleep architecture are minimal, and that the decision of whether or not to use the technique can be based to a large extent on whether quantitative information about respiratory effort will be useful.

Adolescent↗
PubMed1997

Usefulness of polysomnography in epilepsy patients.

We reviewed the records of 63 adult epilepsy patients who underwent polysomnograms in our laboratory since 1985 to determine the indications for polysomnography and the results of testing. Reasons for referral included excessive daytime sleepiness, suspected obstructive sleep apnea (OSA), and characterization of nocturnal spells. The most common polysomnographic diagnosis was OSA, although we also found narcolepsy, insufficient sleep syndrome with possible idiopathic hypersomnolence, and previously unrecognized nocturnal seizures. We treated OSA with continuous positive airway pressure in 28 patients, 15 of whom were using the device at follow-up appointments. The majority of patients treated for OSA or other disorders reported an improvement in sleepiness or seizure control. Polysomnography, when indicated, is beneficial in epilepsy patients.

Adult↗
PubMed1997

Value of the multiple sleep latency test (MSLT) for the diagnosis of narcolepsy.

Since its introduction, the multiple sleep latency test (MSLT) has played a major role in the diagnosis of narcolepsy. We assessed its diagnostic value in a series of 2,083 subjects of whom 170 (8.2%) were diagnosed with narcolepsy. The sensitivity of the combination of two or more sleep onset rapid eye movement (REM) periods (SOREMPs) with a mean sleep latency of < 5 minutes on an initial MSLT was 70% with a specificity of 97%, but 30% of all subjects with this combination of findings did not have narcolepsy. In some narcoleptics who had more than one MSLT, the proportion of naps with SOREMPs varied substantially from the initial MSLT to the follow-up test. The highest specificity (99.2%) and positive predictive value (PPV) (87%) for MSLT findings was obtained with the criteria of three or more SOREMPs combined with a mean sleep latency of < 5 minutes, but the sensitivity of this combination was only 46%. The combination of a SOREMP with a sleep latency < 10 minutes on polysomnography yielded a specificity (98.9%) and PPV (73%) almost equal to those obtained from combinations of MSLT findings, but the sensitivity was much lower. Our results suggest that the MSLT cannot be used in isolation to confirm or exclude narcolepsy, is indicated only in selected patients with excessive daytime sleepiness, and is most valuable when interpreted in conjunction with clinical findings.

Adolescent↗
PubMed1996

Major histocompatibility class II molecules in the CNS: increased microglial expression at the onset of narcolepsy in canine model.

Human narcolepsy is a neurological disorder known to be closely associated with HLA-DR2 and DQB1*0602. Because most autoimmune diseases are HLA-associated, a similar mechanism has been proposed for narcolepsy. However, neither systemic nor CNS evidence of an autoimmune abnormality has ever been reported. In this study, major histocompatibility (MHC) class I and class II expression was studied in the CNS of human and canine narcoleptics using immunohistochemistry and Northern analysis. Results indicated that canine narcolepsy is associated with a significant increase of MHC class II expression by the microglia. Moreover, the highest values were found between 3 and 8 months of age, strikingly concomitant to the development of narcolepsy in the canine model. In humans, class II expression was not found significantly different between control and narcoleptic subjects. This result could be explained by the old age of the subjects (69.86 +/- 5.31 and 68.36 +/- 4.74 years in narcoleptics and controls, respectively), because class II expression is significantly correlated with age in both humans and dogs. For the first time, this study demonstrated that the expression of MHC class II molecules in the CNS is age-dependent and that a consistent increase of their expression by the microglia might be critically involved in the development of narcolepsy.

Aged↗
PubMed1996

Narcolepsy.

Narcolepsy is among the leading causes of excessive daytime sleepiness and is the most common neurologic cause. Its classic form--narcolepsy with cataplexy--is a distinct neurologic disease with characteristic clinical and paraclinical findings. The history, epidemiology, clinical picture, pathophysiology, cause, diagnosis, and treatment, both pharmacologic and nonpharmacologic, are discussed in detail.

Adult↗
PubMed1996

The clinical spectrum of narcolepsy and idiopathic hypersomnia.

To better define the clinical spectra of narcolepsy and idiopathic hypersomnia, we retrospectively compared clinical and polygraphic findings and questionnaire results in groups of subjects with narcolepsy with or without cataplexy, idiopathic hypersomnia, insufficient sleep syndrome, mild sleep apnea, and excessive daytime sleepiness not otherwise specified. Sleep paralysis and sleep-related hallucinations were most frequent in narcolepsy-cataplexy, but their frequency did not differ between narcolepsy without cataplexy and idiopathic hypersomnia. Mean durations of nocturnal sleep, daytime naps, and morning grogginess were not increased in idiopathic hypersomnia compared with other groups. Among subjects without cataplexy, symptoms of sleep paralysis and sleep-related hallucinations were equally common in subjects with and without frequent sleep-onset REM periods. These findings suggest that the occurrence of these symptoms in subjects without classical narcolepsy-cataplexy is a function of factors other than a propensity for early onset of REM sleep and indicate a need to reevaluate diagnostic criteria for narcolepsy and idiopathic hypersomnia.

Adult↗
PubMed1996

Sleep apnea in patients with transient ischemic attack and stroke: a prospective study of 59 patients.

Although sleep apnea (SA) appears to be a cardiovascular risk factor, little is known about its frequency in patients with transient ischemic attack (TIA) and stroke. We prospectively studied 59 subjects (26 women and 33 men; mean age, 62 years) with stroke (n = 36) or TIA (n = 23) with the use of a standard protocol that included assessment of snoring and daytime sleepiness (Epworth Sleepiness Score [ESS]), a validated SA score (Sleep Disorders Questionnaire [SDQ-SA]), and a severity of stroke score (Scandinavian Stroke Scale [SSS]). SA was considered clinically probable (P-SA) when habitual snoring was associated with an ESS of > 10 or when SDQ-SA score was > or = 32 in women and > or = 36 in men. Polysomnography (PSG) was obtained in 36 subjects (group 1) a mean of 12 days after TIA or stroke. In 23 subjects (group 2), PSG was not available (n = 11), refused (n = 10), or inadequate (n = 2). Clinical and PSG data were compared with those obtained in 19 age- and gender-matched control subjects. Groups 1 and 2 were similar in mean age (61 versus 64 years), type of event (36% versus 44% TIA), reported habitual snoring (58% versus 52%), and P-SA (58% versus 50%). PSG showed SA (Apnea-Hypopnea Index [AHI], > or = 10) in 25 of 36 subjects (69%). The proportion of subjects with SA was similar in the TIA and stroke groups (69% versus 70%) and was well above the frequency found in our control group (15%). An AHI of > or = 20 and a minimal oxygen saturation of < 85% were each found in 20 of 36 subjects (55%). Gender and age did not correlate with severity of SA. Subjects with habitual snoring, P-SA, or severe stroke (SSS of < 30) had a significantly higher AHI (p < 0.05). The sensitivity of P-SA for SA was 64%, and the specificity was 67%. We conclude that SA has a high frequency in patients in the acute phase of TIA and stroke and SA cannot be predicted reliably on clinical grounds alone but is more likely in patients with habitual snoring, abnormal SDQ-SA, or severe stroke.

Adult↗
PubMed1994

Patterns of sleep and wakefulness in treated narcoleptic subjects.

In most reported studies of treatment for narcolepsy, the efficacy of treatment has been assessed in the sleep laboratory, but not in the natural work and home settings. We therefore assessed the sleep/wake patterns of 25 subjects with narcolepsy, whose symptoms were considered under satisfactory control by the subjects and their physicians, using polygraphic recorders, and compared these with the patterns of 25 control subjects matched for age and gender. Data from one matched pair of subjects were excluded for technical reasons. There was no difference between the two groups of subjects in the total amount of sleep obtained during the 24-hour monitoring period. Narcoleptic subjects had shorter nocturnal sleep latencies and more disrupted nocturnal sleep than control subjects. Despite taking their usual medications, narcoleptic subjects averaged 44 minutes of daytime sleep compared to 4.8 minutes for controls. There was wide variation in the amount of daytime sleep among narcoleptics: 10 subjects did not sleep during the day, whereas the other 14 averaged 2.7 naps per day for an average of 76.2 minutes of daytime sleep. These findings indicate that daytime sleep episodes were common in narcoleptic patients who considered their treatment satisfactory. Wide variations in the amount of daytime sleep may reflect differences in disease severity, responsiveness to medications or willingness to tolerate daytime sleep episodes.

Adolescent↗
PubMed1994

Neurochemical studies of human narcolepsy: alpha-adrenergic receptor autoradiography of human narcoleptic brain and brainstem.

Studies of human and canine narcolepsy-cataplexy syndrome suggest that noradrenergic function may be abnormal. We used quantitative autoradiography to assess noradrenergic alpha-1 and alpha-2 receptors in several regions of seven human narcoleptic and 18 control brains using [3H]prazosin to evaluate alpha-1 receptors, and [3H]UK14304 and [3H]rauwolscine to evaluate alpha-2 receptors. Specific blocking agents were used in combination with the tritiated ligands to assess alpha-1 and alpha-2 receptor subtypes. Although we found few statistically significant differences between narcoleptic and control brains, there were a number of trends. [3H]Prazosin binding to sites in the amygdala, globus pallidus and putamen was reduced by 22-68%, whereas binding was increased by 40% to the inferior olive and by 84% to portions of the dorsal pons. Binding was similar to control values in other regions. In all seven brainstem regions that were evaluated, the ratio of alpha-1b receptor binding to alpha-1a receptor binding was increased. Binding of [3H]UK14304 was increased by 35-74% in the caudate nucleus, putamen and portions of the amygdala and pons. [3H]rauwolscine binding data suggested that increase of alpha-2 receptor binding in the dorsal pons were not due to effects at the imidazole receptor. findings suggest that noradrenergic function may be altered in specific regions of the brain and brainstem in human narcolepsy, although the absence of statistical significance indicates that these trends should be considered preliminary. The trend toward a relative increase of alpha-1b receptor binding in narcoleptic brainstem is consistent with data from studies of canine narcolepsy and suggests that altered activity at this receptor may contribute to the pathogenesis of human narcolepsy. Studies of additional brains will be required to confirm these findings.

Adult↗
PubMed1993

Insomnia in neurological diseases.

Sleep disturbance, common in many neurological diseases, can be caused by underlying CNS pathology, altered motor system function, associated cognitive and psychiatric disorders, secondary effects of the disease such as pain and immobility, and medication effects. Nocturnal behavioral disturbances are a major contributor to institutionalization of such patients, and respiratory abnormalities of sleep can be life-threatening. Rational approach to diagnosis and treatment can lead to significant improvements in many such patients.

Basal Ganglia Diseases↗
PubMed1993

Autoradiographic studies of post-mortem human narcoleptic brain.

Although the pathological basis for narcolepsy is unknown, studies of human and canine narcolepsy have suggested that monoamine and cholinergic metabolism may be altered. We used quantitative autoradiography to assess binding of dopaminergic, noradrenergic, and cholinergic ligands to basal ganglia and amygdala of five narcoleptic and 17 control human brains. Dopamine receptor studies revealed significant increases in D-1 and D-2 receptor binding in the caudate nucleus, as well as large but not significant increases of D-1 binding in the medial globus pallidus, and D-2 binding in the lateral globus pallidus and the lateral nucleus of the amygdala. Alpha-adrenergic receptor studies revealed a significant increase in alpha-2 receptor binding in the putamen and large but not significant increases of alpha-2 binding in the caudate nucleus, and basal and lateral nuclei of the amygdala. Alpha-1 receptor binding was decreased in several areas but the changes were not statistically significant. Studies of two narcoleptic brains revealed small but not statistically significant increases in muscarinic receptor binding in the caudate nucleus, putamen, and amygdala. Although we cannot exclude the possibility that stimulant medications used before death may be partly responsible for these findings, the results suggest that human narcolepsy is associated with upregulation of dopamine and alpha-2 adrenergic receptors in specific brain regions.

Adult↗