PubMed Health⌕ Search

Biomedical subjects

M R Pressman

Publications and source records attributed to M R Pressman.

At least 19 recordsLinked to original sources
PubMed2000

Potential novel predictors of mortality in end-stage renal disease patients with sleep disorders.

Patients with end-stage renal disease (ESRD) have an annual mortality rate exceeding 20%, although some survive many years. The ESRD population has a high incidence of sleep disorders, including sleep apnea and periodic limb movements in sleep (PLMS). Sleep disorders result in sleep deprivation, which can negatively affect immune function and cardiovascular-related outcomes, common causes of death in patients with ESRD. This study examined predictors of mortality in patients with ESRD with sleep problems. Twenty-nine consecutive patients with ESRD reporting disrupted sleep or daytime sleepiness were studied by all-night polysomnography. All patients were followed up until death, transplantation, or study termination. Among the variables studied, including such previously reported predictors as serum albumin level, urea reduction ratio, and hematocrit, only the PLMS index (PLMSI), arousing PLMSI (APLMSI), and total number of arousals per hour of sleep significantly predicted mortality. The 20-month survival rate with a PLMSI less than 20 was greater than 90% versus 50% for a PLMSI of 20 or greater (exact log-rank, P = 0.007). For the deceased versus survivor groups, mean PLMSI was 119.1 versus 19.8 (P = 0.01) and APLMSI was 48.1 versus 7.8 (P = 0.00006), with a mean survival of 10.3 versus greater than 25.5 months, respectively (P = 0.001). Median survival of patients with a PLMSI greater than 80 was only 6 months. PLMSI, APLMSI, and total arousals per hour of sleep were strongly associated with mortality in patients with ESRD with sleep disorders independent of other factors and may be novel predictors of near-term mortality.

Aged↗
PubMed1999

A preliminary study of the effects of correction of anemia with recombinant human erythropoietin therapy on sleep, sleep disorders, and daytime sleepiness in hemodialysis patients (The SLEEPO study).

End-stage renal disease (ESRD) is commonly associated with complaints of disturbed sleep and sleep disorders, frequently related to periodic limb movements in sleep (PLMS) or sleep apnea that may result in daytime sleepiness and other sequelae. Improvements in quality of life, including subjective sleep quality, have been reported in ESRD patients treated with recombinant human erythropoietin (rHuEPO). We investigated the objective effects of normalizing hematocrit on sleep disorders, sleep patterns, and daytime ability to remain awake in ESRD patients. Ten hemodialysis patients with sleep complaints while on rHuEPO therapy were studied by polysomnography while moderately anemic (mean hematocrit, 32.3%) and again when hematocrit was normalized (mean hematocrit, 42.3%) by increased rHuEPO dosing. Sleep patterns and associated parameters were monitored. Delivered dialysis dose and iron storage factors were monitored. Maintenance of Wakefulness Testing (MWT) was performed to assess daytime alertness/sleepiness. All 10 subjects experienced highly statistically significant reductions in the total number of arousing PLMS (P = 0.002). Nine of 10 subjects showed reductions in both the Arousing PLMS Index (P < 0.01) and the PLMS Index (P = 0.03) when hematocrit was normalized. Measures of sleep quality showed trends to improved quality of sleep. MWT demonstrated significant improvement in the length of time patients were able to remain awake (9.7 versus 17.1 minutes; P = 0.04). RHuEPO therapy with full correction of anemia reduces PLMS, arousals from sleep, and sleep fragmentation while allowing for more restorative sleep and improved daytime alertness. These findings may explain one mechanism for the improved quality-of-life parameters reported in ESRD patients treated with rHuEPO.

Adult↗
PubMed1997

Air leaking through the mouth during nocturnal nasal ventilation: effect on sleep quality.

Air leaking through the mouth has been reported in kyphoscoliotic patients receiving nasal ventilation via volume-limited ventilators. This study accessed the frequency of occurrence and effect on sleep quality of air leaking through the mouth during nocturnal nasal ventilation in patients with chest wall and neuromuscular disease using pressure-limited ventilation. Overnight and daytime polysomnography was performed in six stable experienced users of nocturnal nasal noninvasive positive-pressure ventilation (NPPV) who had chronic respiratory failure due to neuromuscular disease or chest wall deformity. All patients used the BiPAP S/T-D ventilatory support system (Respironics, Inc., Murrysville, PA). Measures included sleep scoring, leak quantitation, diaphragm and submental electromyograms (EMGs), and tidal and leak volumes. All patients had air leaking through the mouth for the majority of sleep. Sleep quality was diminished because of poor sleep efficiency and reduced percentages of slow-wave and rapid eye movement (REM) sleep. Air leaking through the mouth was associated with frequent arousals during stages 1 and 2 and REM sleep that contributed to sleep fragmentation, but arousals were infrequent during slow-wave sleep. Despite prevalent leaking, oxygenation was well maintained in all but one patient. Patients used a-combination of passive and active mechanisms to control air leaking. Although nasal ventilation improves nocturnal hypoventilation and symptoms in patients with restrictive thoracic disorders, air leaking through the mouth is very common during use. The leaking is associated with frequent arousals during lighter stages of sleep that interfere with progression to deeper stages, compromising sleep quality. Portable pressure-limited ventilators compensate for leaks, maintaining ventilation and oxygenation, but further studies are needed to determine which interfaces and ventilator techniques best control air leaking and optimize sleep quality.

Adult↗
PubMed1996

Nocturia. A rarely recognized symptom of sleep apnea and other occult sleep disorders.

BACKGROUND: Nocturia, awakening from sleep to urinate, is a common symptom in a variety of medical disorders and in the elderly. Awakening from sleep as a result of nocturia is thought to be secondary to a sensation of urinary urgency resulting from an overextended bladder. Nocturia-related awakenings cause significant sleep disruption and fatigue in elderly patients and are correlated with an increased number of falls at night. Sleep disorders such as sleep apnea are also common in the elderly and are frequently the source of awakenings from sleep. The high incidence of both nocturia and sleep disorders in the elderly and other groups of patients suggests that sleep disorders may be the source of some awakenings from sleep usually attributed by patients to nocturia. Nocturia secondary to sleep disorders would be causatively different from nocturia secondary to pressure to urinate in common medical disorders and would require different diagnostic procedures and treatment. OBJECTIVE: To determine the frequency of nocturia as a symptom of primary sleep disorders. METHODS: Eighty consecutive patients, 27 women and 53 men with a mean (+/-SD) age of 58.7+/-14.1 years, undergoing polysomnography (sleep study or PSG) for the evaluation of a suspected sleep disorder and who met the sole criteria of awakening from sleep at least once and urinating voluntarily. Each patient had either a standard PSG recording or a PSG with administration of nasal continuous positive airway pressure. Immediately after each episode of nocturia during the PSG, patients were questioned about the reason they believed they had awakened. The PSG record immediately before awakening from sleep was then reviewed for potential causes of awakening. Patients were also asked on final morning awakening to fill in a questionnaire regarding their awakenings during the prior night. Patient reports were compared with the PSG to determine the accuracy of subjective reports. RESULTS: Patients awakened from sleep and voluntarily urinated a mean (+/- of 1.5+/-0.75 times per night for a total of 121 awakenings for the group. The majority (79.3%) of these awakenings from sleep were found to be directly secondary to sleep apnea, snoring or periodic leg movements in sleep. Patients correctly identified the source of their awakening from sleep on only five(4.9%) occasions and only once was sleep apnea correctly cited by a patient as a source of awakening during the night. CONCLUSION: Most awakenings from sleep attributed by our patients to pressure to urinate were instead a result of sleep disorders, particularly sleep apnea. The fact that patients do urinate once awake likely contributed to faulty post hoc reasoning and might have limited further inquiry by patients and their physicians in clinical settings into the actual sources of awakening from sleep. Even in those patients with well-known medical reasons for noctruria, Sleep disorders were still found to be the source of almost all awakenings from sleep. Patients were extremely poor judges of the reasons they awoke from sleep. The diagnosis of a sleep disorder should be seriously considered whenever a patient reports frequent awakenings from sleep to urinate.

Adult↗
PubMed1995

Night terrors in an adult precipitated by sleep apnea.

Parasomnias are generally described as disorders of arousal that arise out of stage 3 and 4 nonrapid eye movement (NREM) sleep without identifiable cause. We present a case of a 35-year-old man who during nasal continuous positive airway pressure (nCPAP) treatment for severe obstructive sleep apnea experienced an intense night terror triggered by a residual obstructive apnea during rebound deep sleep. The role of rebound deep sleep was thought to be essential in creating a state of sleep with a high arousal threshold hypothesized to be important for the occurrence of parasomnias. This case supports the clinical wisdom that identifiable sources of arousal can trigger parasomnias.

Humans↗
PubMed1995

Transient ischemic attacks and minor stroke during sleep. Relationship to obstructive sleep apnea syndrome.

BACKGROUND: It is reported that 13% to 44% of all cerebrovascular accidents (CVAs) occur during sleep. In addition to other well-known risk factors, snoring, sleep apnea, obesity, and daytime sleepiness have been shown to significantly increase the risk of stroke. We describe two cases that support the statistical relationship between snoring, sleep apnea, and CVA during sleep. CASE DESCRIPTIONS: In the first case, motor aphasia was noted in a 64-year-old, 5-ft, 1-in, 218-lb woman when she awakened from sleep at approximately 4 AM. This completely resolved within 3 hours. During her subsequent hospitalization she was found to have severe obstructive sleep apnea that responded well to treatment with nasal continuous positive airway pressure. There has been no recurrence of symptoms in this patient. The second patient was a 59-year-old, 5-ft, 6-in, 260-lb woman who presented to the Sleep Disorders Center with signs and symptoms of severe sleep apnea. In addition, she had awakened from sleep approximately 6 months earlier with numbness and weakness on her right side. Although these symptoms had greatly improved, she continued to complain about residual weakness that was worse on awakening from sleep. Sleep studies confirmed severe obstructive sleep apnea that responded very well to treatment with nasal continuous positive airway pressure. CONCLUSIONS: Snoring and obstructive sleep apnea not only increase the statistical risk of CVA but could be the proximal trigger that precipitates these events during sleep. These two cases provide clinical support for this relationship. Successful diagnosis and treatment of obstructive sleep apnea in the patient with transient ischemic attacks and minor stroke may be an important tool for preventing recurrence.

Female↗
PubMed1995

Ramp abuse. A novel form of patient noncompliance to administration of nasal continuous positive airway pressure for treatment of obstructive sleep apnea.

Administration of nasal continuous positive airway pressure (NCPAP) is the treatment of choice for most patients with obstructive sleep apnea. Many patients experience side effects with NCPAP use, and the compliance rate is reported to vary between 46-89%. The ramp is a device found on many NCPAP machines that resets the pressure to 3 cm H2O and then slowly increases the pressure to the prescribed pressure over a period of up to 45 min. The ramp allows patients time to fall asleep before the higher and likely more uncomfortable prescribed pressure is administered. We present a case in which a patient's repeated remote-controlled activation of this ramping feature severely limited effective therapy even when the NCPAP mask was properly in place, the machine was on, and the patient was breathing nasally.

Female↗
PubMed1993

Sleep disordered breathing in ESRD: acute beneficial effects of treatment with nasal continuous positive airway pressure.

Complaints about sleep and daytime alertness are common in ESRD patients. Eight consecutive ESRD patients with a sleep complaint were studied with all-night polysomnography. All were found to have significant sleep apnea with a mean apnea/hypopnea index (AHI) of 64 +/- 41.6 episodes per hour of sleep (range 7.5 to 140/hr of sleep). The majority of apneas were of the central or mixed variety causing severe fragmentation of sleep and frequent awakenings. Treatment was attempted with nasal continuous positive airway pressure (NCPAP). NCPAP was highly successful in six of the eight patients, reducing the mean AHI to normal or near normal levels (6.0 +/- 3.8/hr of sleep, P < 0.02 vs. baseline). The quality of sleep was significantly improved with statistically significant decreases in light stage 1 sleep, and nocturnal oxygenation improved with statistically significant increases in low SaO2 values. Five of six responders reported that they awoke feeling more alert and fewer times from sleep. The etiology of sleep apnea in ESRD is unknown although the frequent central apneas suggest a dysfunction of central respiratory control resulting from the effects of renal failure. Sleep-related complaints in patients with ESRD are likely to result from sleep apnea, a sleep disorder that can be diagnosed with polysomnography and treated with NCPAP.

Body Weight↗
PubMed1989

Avoiding false positive findings in measuring nocturnal penile tumescence.

The measurement and interpretation of nocturnal penile tumescence (NPT) studies depend on appropriate measurement techniques, knowledge of the conditions during which NPT was recorded, and a lack of preconceived notions about the relationship of penile circumference to penile rigidity. This case report illustrates several of the most common problems in the measurement and interpretation of NPT that could result in a false positive finding.

Aged↗
PubMed1989

Relationship of autonomic nervous system activity to daytime sleepiness and prior sleep.

Autonomic nervous system (ANS) measures have been used frequently as measures of activation or arousal. However, their relationship to standard measures of alertness--the Multiple Sleep Latency Test (MSLT) and Stanford Sleepiness Scale (SSS)--and to the quantity and quality of prior sleep has not been determined. In this study, the direct pupil light reflex (PLR) was measured with the MSLT and SSS to determine how ANS activity varies with daytime sleepiness and how all three measures were related to prior nocturnal sleep in a group of patients with obstructive sleep apnea. When the effects of age and time of day were partialed out, PLR data suggest that increased sleepiness as measured by MSLT is significantly correlated with increased parasympathetic activity (r = -0.60, p less than 0.01) and not with decreased sympathetic activity (r = -0.24, not significant). These partial correlations were significantly different (p less than 0.05). Increased sleepiness as measured by the SSS was significantly correlated with decreased sympathetic activity (r = -0.46, p less than 0.05) and not with increased parasympathetic activity (r = -0.00, not significant). These partial correlations were significantly different (p less than 0.02). In the group of sleep apnea patients, the PLR suggests that increased number of apneas and hypopneas (sleep fragmentation) was significantly correlated with both decreased sympathetic activity and increased parasympathetic activity. These findings suggest that ANS activity is related to daytime sleepiness and to the quality of prior sleep.

Arousal↗
PubMed1989

Periodic leg movements in sleep following treatment of obstructive sleep apnea with nasal continuous positive airway pressure.

Periodic leg movements in sleep are shown to be a common finding in patients with OSA and may become evident or increase in severity after treatment of the OSA with NCPAP. Periodic leg movements in sleep were measured during baseline polysomnography, a NCPAP treatment trial, and a repeat NCPAP recording in 33 patients treated with NCPAP for OSA. During baseline PSG, nine patients had five or more PLMS per hour of sleep (index), while 14 patients had a PLMSI of 5 or more during the NCPAP trial and the repeat NCPAP recording. Among those patients with a PLMSI of 5 or more during repeat NCPAP studies, the PLMSI showed a significant increase from baseline to initial NCPAP (16.9 +/- 25.3 vs 39.3 +/- 29.4; p less than 0.001) and from baseline to repeat NCPAP (16.9 +/- 25.3 vs 42.9 +/- 39.8; p less than 0.05). The number of PLMS associated with electroencephalographic arousal also increased significantly from baseline to initial NCPAP (4.3 +/- 7.4 vs 9.7 +/- 8.9; p less than 0.05) and from baseline to repeat NCPAP (4.3 +/- 7.4 vs 16.5 +/- 18.6; p less than 0.05). The 14 patients with a PLMSI of 5 or more on the repeat NCPAP had significantly more stage 1 sleep and less REM sleep than 19 patients with a PLMSI of less than 5. Bilateral anterior tibialis EMG must be measured during NCPAP recordings in order to recognize sleep disruption caused by PLMS.

Electroencephalography↗
PubMed1988

What is normal sleep in the elderly?

Changes in the sleep and daytime alertness of the elderly are common and are secondary to a variety of causes. These changes cannot be attributed solely to the aging process. The role of occult sleep disorders in producing these changes in significant, and severe sleep disruption in the healthy elderly is almost always secondary to a sleep disorder such as sleep apnea. A number of precautions must be kept in mind when interpreting studies of sleep in the elderly.

Aged↗
PubMed1986

Problems in the interpretation of nocturnal penile tumescence studies: disruption of sleep by occult sleep disorders.

A review of the sleep of 31 patients 45 years old or older undergoing nocturnal penile tumescence studies showed that 19 had a previously undiagnosed sleep disorder. Of the patients 9 had periodic leg movements in sleep, 9 had sleep apnea and 1 had both disorders. In 10 of these patients the sleep disorders affected nocturnal penile tumescence by disrupting sleep and causing brief periods of detumescence, movement artifacts and delays in the tumescing phase of nocturnal penile tumescence. These disruptions resulted in an apparently abnormal nocturnal penile tumescence that appeared as if the patient had difficulty in achieving or maintaining an erection. The nocturnal penile tumescence disruptions may have reflected only a disruption of the necessary conditions for normal nocturnal penile tumescence to occur, namely adequate sleep and rapid eye movement sleep. The results strongly suggest that failure to measure concurrent sleep parameters and screen for occult sleep disorders could result in the incorrect diagnosis of abnormal nocturnal penile tumescence.

Aged↗
PubMed1986

Senile miosis: the possible contribution of disordered sleep and daytime sleepiness.

The contribution of disordered sleep and daytime sleepiness to senile miosis was investigated in 23 participants aged 60 to 80 years and 12 participants aged 21 to 40 years. All participants filled out questionnaires and were interviewed about their health, sleep, and daytime alertness. On this basis the older group was subdivided into a group of 13 participants with sleep disorders or daytime sleepiness and 10 participants without. All participants were studied with a computerized infrared television pupillometry system for 15 s in ambient lighting, 15 s after 5 min dark adaptation and with 5 light flashes. Pupil diameter after dark adaptation was significantly larger in the older group without sleep disorders than in the older group with sleep disorders (5.94 +/- .73 mm vs. 4.49 +/- .62 mm, M +/- SD, p less than .001). Significant partial correlation coefficients controlled for age were found between pupillary diameter and a variety of sleep variables. The data suggest that occult sleep disorders and daytime sleepiness may contribute to senile miosis.

Adult↗
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↗
PubMed1986

Treatment of narcolepsy with codeine.

The effectiveness of codeine as a treatment for the excessive daytime sleepiness of narcolepsy was studied in two experimental trials. In an open trial of codeine in five narcoleptic subjects, dramatic clinical improvement was reported. However, all-night polysomnography and maintenance of wakefulness tests before and after codeine showed no significant differences. A double-blind placebo-codeine trial was conducted in which eight narcoleptic subjects received codeine for 1 week and placebo for 1 week in a random order. During the week they kept a diary, and on the sixth evening and for 10 h following awakening on the seventh day they were monitored by radiotelemetry in the sleep laboratory for electroencephalogram, electro-oculogram, and electromyogram. The results were analyzed for sleep stages as well as four levels of wakefulness. The results showed no significant differences in any of the objective sleep or wakefulness parameters. However, the diaries showed significantly fewer naps during the week on codeine as compared with the placebo week. Eighteen of 27 narcoleptic patients treated with codeine report clinical improvement. Codeine consistently results in subjective clinical improvement. However, this is not reflected in the objective measures generally used to assess daytime sleepiness.

Adult↗
PubMed1986

Effects of low-dose naloxone on subjective alertness and pupil diameter in normal and narcoleptic subjects.

Recent evidence suggests that endogenous opiates may be involved in the pathophysiology of narcolepsy. To test this theory, the effect of 0.8 mg naloxone hydrochloride on pupil size and subjective alertness was measured in normal and narcoleptic subjects. Naloxone resulted in significant pupillary constriction in the normal but not in the narcoleptic subjects. The extent of contraction of the pupil light reflex was reduced significantly in the narcoleptic but not in the normal subjects. There was no effect on subjective ratings of alertness on the Stanford Sleepiness Scale or the visual analogue scale in either group. The naloxone-related miosis in the normal group confirms that naloxone is not a pure opiate antagonist. The lack of naloxone-related miosis in the narcoleptics suggests that narcoleptic individuals do not respond to naloxone as do normal individuals. However, this difference can not be definitely attributed to the antagonism of endogenous opiates. The reduction of the extent of contraction of the light reflex suggests that naloxone caused an increase in supranuclear inhibition of parasympathetic pupil reflex activity. However, this finding may have resulted from mechanical limitations of a small pupil or technical limitations of the recording equipment. This study does not support previous reports that naloxone causes an increase in subjective alertness in narcoleptics.

Adult↗