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Biomedical subjects

C Guilleminault

Publications and source records attributed to C Guilleminault.

At least 127 records · Page 7Linked to original sources
PubMed1997

Diaphragm pacing for respiratory insufficiency.

Diaphragm pacing (DP) by electrical stimulation of the phrenic nerve offers important advantages to a highly select group of patients with respiratory paralysis. The patient wears an external radiofrequency (RF) transmitter over an implanted receiver, and a stimulating current is induced without the need for any transcutaneous wires. We review the conditions and requirements of patients who may benefit most from DP. We outline the preoperative evaluation and procedures for surgical implantation. We discuss the risk of diaphragmatic fatigue posed by initiation of DP and the use of gradual conditioning to limit this problem. Other problems encountered by patients in the course of DP can be minimized by well-instructed home caregivers and by systematic medical follow-up. Although a few patients derive considerable benefit from DP, many patients with respiratory paralysis are better treated by less invasive means such as nasal bilevel positive airway pressure or intermittent positive pressure ventilation, which we also review.

Contraindications↗
PubMed1997

Prevalence and correlates of nocturnal desaturations in a sample of elderly people.

We designed an epidemiological study to estimate the prevalence and correlates of nocturnal desaturations in a sample of elderly subjects from the general population. Sleep-related respiratory disturbances were assessed by questionnaire and MESAM IV (MADAUS electronic sleep apnoea monitor) ambulatory monitoring. An oxygen desaturation index (ODI), oxygen desaturation being defined as a decrease in SaO2 of or exceeding 4%, was then computed from these data. An oxygen desaturation index > or = 10 was observed in 27.0% of the 293 subjects studied (mean age 76.6+/-5.7 y, median=75 y, min.=69, max.=99), an oxygen desaturation index > or = 30in 4.4%. Multivariate analysis identified as correlates to an oxygen desaturation index > or = 10: male gender (OR=1.80; P=0.04), a high body mass index (BMI) in men (OR=1.20 per kg m2; P=0.0009), and advanced age in women (OR=1.09 per y; P=0.02). A positive association was found between loud snoring (OR=1.75; P=0.06) and an oxygen desaturation index > or = 10. However, there was no statistically significant relationship between an oxygen desaturation index > or = 10 and either daytime somnolence (OR=1.50; P=0.19) or trouble getting to sleep (OR=0.59; P=0.09). We found no significant relationship in our sample between oxygen desaturation index and arterial hypertension or cardiac dysrhythmia. Previous studies on younger populations have reported different results. It may well be the advanced age of our sample that explains these inconsistencies. For the elderly persons we studied our results underline the relatively high prevalence of sleep-related respiratory disturbances. However, these may be of less consequence than in younger populations.

Aged↗
PubMed1997

Extensive HLA class II studies in 58 non-DRB1*15 (DR2) narcoleptic patients with cataplexy.

Narcolepsy is a sleep disorder that has been shown to be tightly associated with HLA DR15 (DR2). In this study, 58 non-DR15 patients with narcolepsy-cataplexy were typed at the HLA DRB1, DQA1 and DQB1 loci. Subjects included both sporadic cases and narcoleptic probands from multiplex families. Additional markers studied in the class II region were the promoters of the DQA1 and DQB1 genes, two CA repeat polymorphisms (DQCAR and DQCARII) located between the DQA1 and DQB1 genes, three CA repeat markers (G51152, T16CAR and G411624R) located between DQB1 and DQB3 and polymorphisms at the DQB2 locus. Twenty-one (36%) of these 58 non-DR15 narcoleptic patients were DQA1*0102 and DQB1*0602, a DQ1 subtype normally associated with DRB1*15 in DR2-positive narcoleptic subjects. Additional microsatellite and DQA1 promoter diversity was found in some of these non-DR15 but DQB1*0602-positive haplotypes but the known allele specific codons of DQA1*0102 and DQB1*0602 were maintained in all 21 cases. The 37 non-DQA1*0102/DQB1*0602 subjects did not share any particular HLA DR or DQ alleles. We conclude that HLA DQA1*0102 and DQB1*0602 are the most likely primary candidate susceptibility genes for narcolepsy in the HLA class II region.

Cataplexy↗
PubMed1997

A survey of habitual snoring in centenarians.

OBJECTIVE: To ascertain whether centenarians in the surveyed group would be nonhabitual snorers. DESIGN AND SETTING: A cross-sectional survey of centenarians residing in the Aichi Prefecture of Japan. PARTICIPANTS: A total of 103 centenarians (21 men and 82 women). MEASUREMENTS: Questionnaire on sleep habits, breathing, and snoring. RESULTS: Nineteen centenarians (18.4%; 5 men and 14 women) were habitual snorers and two (1.9%) were suspected of having sleep apnea syndrome because of the presence of heavy snoring and nocturnal respiratory arrest. CONCLUSION: Most centenarian subjects were nonsnorers and without breathing pauses during sleep; their snoring rates were no different from those of younger aged older adults in the same population.

Adolescent↗
PubMed1997

DSM-IV and ICSD-90 insomnia symptoms and sleep dissatisfaction.

BACKGROUND: The complex nature of insomnia and its relationship with organic and mental disorders render diagnosis problematic for epidemiologists and physicians. METHOD: A representative UK sample (non-institutionalised, > 14 years old) was interviewed by telephone (n = 4972; 79.6% participation rate) with the Sleep-EVAL system. Subjects fell into three groups according to presence of insomnia symptom(s) and/or sleep dissatisfaction. RESULTS: Insomnia symptoms occurred in 36.2% of subjects. Most of these (75.9%), however, reported no sleep dissatisfaction. In comparison, those also with sleep dissatisfaction had higher prevalence of sleep and mental disorders and longer duration of insomnia symptoms, and were more likely to take sleep-promoting medication, dread bedtime, and complain of light sleep, poor night-time sleep and daytime sleepiness. CONCLUSIONS: Insomnia sufferers differ as to whether they are satisfied or dissatisfied with sleep. Although insomnia symptoms are common in the general population, sleep disturbances among sleep-dissatisfied individuals are more severe. Sleep dissatisfaction seems a better indicator of sleep pathology than insomnia symptoms.

Adolescent↗
PubMed1997

HLA DR15 (DR2) and DQB1*0602 typing studies in 188 narcoleptic patients with cataplexy.

Narcolepsy is considered a homogeneous clinical entity when excessive daytime sleepiness and cataplexy are present. Cataplexy is a polymorphic symptom that can be very mild and is thus subjectively defined. The Multiple Sleep Latency Test (MSLT) is widely used as a diagnostic test for narcolepsy. A short mean sleep latency and multiple sleep onset REM periods (SOREMPs) are typically observed in narcoleptic patients. The discovery of a tight association of narcolepsy with HLA class II antigens offers a unique opportunity to explore the respective value of the MSLT or of the presence of clear-cut cataplexy in defining an etiologically homogeneous group of narcoleptic patients. In this study, we carried out HLA typing for DR15(DR2) and DQB1*0602 in 188 narcoleptic patients with cataplexy in three ethnic groups (24 Asians, 61 Blacks, and 103 Caucasians). These results confirm the importance of DQB1*0602 typing rather than DR15 (DR2) typing in Black narcoleptic patients and demonstrate that the presence of clear-cut cataplexy is a better predictor for DQB1*0602 positivity than the presence of abnormal MSLT results.

Asian People↗
PubMed1997

Radiofrequency volumetric reduction of the tongue. A porcine pilot study for the treatment of obstructive sleep apnea syndrome.

STUDY OBJECTIVE: To investigate, in an animal model, the feasibility of radiofrequency (RF) volumetric tongue reduction for the future purpose of determining its clinical applications in obstructive sleep apnea syndrome (OSAS). DESIGN: The study was performed in three stages, one in vitro bovine stage and two in vivo porcine stages. The last stage was a prospective investigation with histologic and volumetric analyses to establish outcomes. SETTING: Laboratory and operating room of veterinary research center. PARTICIPANTS: A homogeneous population of porcine animal models, including seven in stage 2 and 12 in stage 3. INTERVENTION: RF energy was delivered by a custom-fabricated needle electrode and RF generator to the tongue tissue of both the in vitro and in vivo models. MEASUREMENTS AND RESULTS: Microultransonic crystals were used to measure three-dimensional changes (volumetric reduction). Lesion size correlated well with increasing RF energy delivery (Sperman correlation coefficient of 0.986; p = 0.0003). Histologic assessments done serially over time (1 h through 3 weeks) showed a well-circumscribed lesion with a normal healing progression and no peripheral damage to nerves. Volumetric analysis documented a very mild initial edematous response that promptly tapered at 24 h. At 10 days after RF, a 26.3% volume reduction was documented at the treatment site (circumscribed by the microultrasonic crystals). CONCLUSION: RF, in a porcine animal model, can safely reduce tongue volume in a precise and controlled manner. Further studies will validate the use of RF in the treatment of OSAS.

Animals↗
PubMed1997

Circadian rhythms and enhanced athletic performance in the National Football League.

Circadian rhythms produce daily changes in critical elements of athletic performance. We explored the significance of performing at different circadian times in the National Football League (NFL) over the last 25 seasons. West Coast (WC) NFL teams should have a circadian advantage over East Coast (EC) teams during Monday Night Football (MNF) games because WC teams are essentially playing closer to the proposed peak athletic performance time of day. Retrospective data analysis was applied to all games involving WC versus EC teams playing on MNF with start times of 9:00 p.m. Eastern Standard Time (EST) from the 1970-1994 seasons. Logistic regression analysis of win-loss records relative to point spreads and home-field advantage was examined. West Coast teams win more often (p < 0.01) and by more points per game than EC teams. West Coast teams are performing significantly (p < 0.01) better than is predicted by the Las Vegas odds (the point spread). This apparent advantage enhances home-field advantage for WC teams and essentially eliminates the beneficial effects of home-field advantage for EC teams during MNF games. These results support the presence of an enhancement of athletic performance at certain circadian times of the day.

Circadian Rhythm↗
PubMed1997

HLA DQB1*0602 is associated with cataplexy in 509 narcoleptic patients.

Narcolepsy is a sleep disorder associated with HLA DR15 (DR2) and DQB1*0602. We HLA typed 509 patients enrolled in a clinical trial for the drug modafinil and analyzed the results in relation to cataplexy, a symptom of narcolepsy characterized by muscle weakness triggered by emotions. The patients were either subjects with cataplexy who had a mean sleep latency (SL) of less than 8 minutes and two or more sleep onset rapid eye movement (REM) periods (SOREMPs) during a multiple sleep latency test, or narcoleptic patients without cataplexy but with a mean SL shorter than 5 minutes and two or more SOREMPs. The respective values of DRB1*15 (DR2) and DQB1*0602 as markers for narcolepsy were first compared in different ethnic groups and in patients with and without cataplexy. DQB1*0602 was found to be a more sensitive marker for narcolepsy than DRB1*15 across all ethnic groups. DQB1*0602 frequency was strikingly higher in patients with cataplexy versus patients without cataplexy (76.1% in 421 patients versus 40.9% in 88 patients). Positivity was highest in patients with severe cataplexy (94.8%) and progressively decreased to 54.2% in patients with the mildest cataplexy. A voluntary 50-item questionnaire focusing on cataplexy was also analyzed in 212 of the 509 HLA-typed patients. Subjects with definite cataplexy as observed by an experienced clinician were more frequently HLA DQB1*0602-positive than those with doubtful cataplexy, and the manifestations of cataplexy were clinically more typical in DQB1*0602-positive patients. These results show that the HLA association is as tight as previously reported (85-95%) when cataplexy is clinically typical or severe. We also found that patients with mild, atypical, or no cataplexy have a significantly increased DQB1*0602 frequency (40-60%) in comparison with ethnically matched controls (24%). These results could be explained by increased disease heterogeneity in the noncataplexy group or by a direct effect of the HLA DQB1*0602 genotype on the clinical expression of narcolepsy.

Adolescent↗
PubMed1997

Rapid shift in peak melatonin secretion associated with improved performance in short shift work schedule.

We studied the performance and adaptability of 40 nurses (median age 35 years), 20 on permanent day shift and 20 on permanent night shift with fast rotation of work and days off, matched for age, gender, and socio-familial responsibilities. For 15 days prior to the study, subjects maintained sleep logs and trained for performance tests. Questionnaires were administered to evaluate adaptability to shift work. During the experimental phase, sleep/wake patterns were monitored using sleep logs and activity/inactivity with wrist actigraphy. Performance levels were measured with the four choice reaction time and memory test for seven letters, eight times/day during the wake period, days on and off. On the last day of work and first day off, 6-sulfatoxy-melatonin levels were assayed from urine samples collected every 2 hours. Estimated total sleep time during the 15-day experimental period was not significantly different in the dayshift and nightshift nurses. Night nurses shifted regularly to daytime activities on days off and, as a group, were significantly sleep deprived on work days with napping on the job in 9 of the 20 night shift nurses (mean of 114+/-45 minutes per shift) and a significant performance decrement during the work period. Further analysis revealed two subgroups of night nurses: The majority (14 nurses) had a mean peak of 6-sulfatoxy-melatonin at 0718 hours on days off and no peak during night work while the other 6 night shift nurses presented a fast melatonin shift with two clear peaks on both work and days off. Comparison of performance scores revealed that all nurses performed similarly on days off. Daytime nurses and fast-shifting night nurses had similar scores on work days, while nonshifting night nurses had significantly lower scores at work. Despite similar gender, age, social conditions, and light exposure levels, a minority of the nurses studied possessed the physiological ability to adapt to a fast-shifting sleep-wake schedule of more than 8 hours and were able to perform appropriately in both conditions. This shift was associated with a change in the acrophase of 6-sulfatoxy-melatonin.

Adult↗
PubMed1996

IgH (mu-switch and gamma-1) region restriction fragment length polymorphism in human narcolepsy.

Predisposition to narcolepsy involves genetic factors both in humans and in a canine model of the disorder. In humans, narcolepsy is strongly associated with HLA DR15 and DQB1*0602. In Dobermans and Labradors, narcolepsy is transmitted as a single autosomal recessive gene with full penetrance (canarc-1). Canine narcolepsy is not linked with DLA, the canine equivalent of HLA, but co-segregates with a DNA segment with high homology with the mu immunoglobulin heavy-chain (IgH) switch-like region (S mu). To determine if the IgH locus is involved in genetic predisposition to human narcolepsy, restriction fragment length polymorphisms specific for the IgM and IgG cluster within this locus were studied in sporadic cases of the disease, as well as in five families with two or more affected individuals. Comparisons were made between control populations and both familial and sporadic cases and for patients with and without HLA-DR15 and DQB1*0602. RFLP analysis at the S mu and gamma-1 loci, which cover over 200 kb of 14q32.3, indicates that there is no evidence for any association between the IgH region and human narcolepsy.

Aged↗
PubMed1996

Determinants of sleepiness in automobile drivers.

Governmental agencies do not systematically investigate the presence of daytime sleepiness as a determinant of driving accidents. We surveyed automobile drivers traveling on summer vacations and driving long distances on a European highway. We evaluated their subjective daytime sleepiness while driving and any sleep deprivation just prior to departure. Five-hundred sixty-seven automobile drivers (mean age 37.7 +/- 11 years) were interviewed at a roadside rest-stop. Questions covered the sleep/wake schedule during the year, sleep habits, and the presence of symptoms frequently associated with sleep-disordered breathing. Sleep behavior just prior to departure was compared to the usual sleep schedule during the year. Fifty percent of the responders had a sleep restriction just prior to departure (mean -203 minutes) compared to usual total sleep time during the year; 10% had no nocturnal sleep prior to departure. Drivers younger than 30 years were significantly more acutely sleep deprived than other drivers. Economic migrants (subjects with low economic status) also experienced significant acute sleep restriction.

Accidents, Traffic↗
PubMed1996

Development of circadian rhythmicity of temperature in full-term normal infants.

Twelve full-term infants (7 girls and 5 boys) with normal neurological, behavioral and somatic development were followed at regular intervals during the first 5 months of life to appreciate the development of circadian rectal temperature rhythmicity. Activity and temperature (oral at birth, rectal thereafter) were monitored for a minimum of 60 hours on seven separate occasions: at birth, 3 weeks, 6 weeks, 8 weeks, 10 weeks, 16 weeks and 20 weeks of age. Activity was measured using an actigraph worn on the infant's wrist, and rectal temperature was measured using a rectal probe attached to a portable microprocessor (Vitalog TM). Data points were collected every 2 minutes. No fewer than ten infants were monitored at each session, and no infant missed more than one session. Missing recordings were due to equipment malfunctions, probe expulsions and minor health problems. Six infants out of 12 were successfully monitored at each of the first four sessions, from birth to 8 weeks of age inclusively, and two subjects were successfully monitored at all seven sessions. Periodic regression analysis was performed by least squares curve fit with secondary analysis of variance. Analysis of covariance was performed on repeated measures. There was no evidence of rectal temperature circadian rhythmicity at 3 weeks. Two infants demonstrated a circadian rhythmicity at 6 weeks, and all infants had a circadian rhythmicity at 10 weeks post-natal age. At the time of the first observance of circadian rhythmicity of rectal temperature, the mean delta in temperature from peak to trough was 0.6 +/- 0.3 degrees C. This delta was greater at the 16th week, with a mean value of 1.2 +/- 0.3 degrees C. The trough was seen during the first part of the long nocturnal inactivity period. Circadian rhythmicity of rectal temperature was always observed in the studied subjects before the establishment of a consolidated, long daytime wake period.

Body Temperature Regulation↗
PubMed1996

Obstructive sleep apnea and related disorders.

OSAS, a common cause of disrupted sleep and EDS, result from repetitive closure of the upper airway during sleep. It probably represents the most severe syndrome related to obstruction of the upper airway; less severe forms include UARS, a syndrome characterized by the need for increased effort to breath but no prominent apneas or hypopneas, and primary snoring. Initial clues to the presence of OSAS and related disorders are derived from the history and include loud snoring, EDS or insomnia, and witnessed apneas. Some patients, especially women, may complain mostly of tiredness or fatigue, and children may present with behavioral abnormalities. Obesity, a large neck circumference, and a crowded oropharynx are common on physical examination. Nonobese patients, in particular, often have retrognathia, a high-arched narrow palate, macroglossia, enlarged tonsils, temporomandibular joint abnormalities, or chronic nasal obstruction. The clinical suspicion of obstructed nocturnal breathing is confirmed by overnight polysomnography, and an MSLT may be used to assess sleepiness. Esophageal manometry during polysomnography facilitates diagnosis of UARS. Treatment most commonly consists of nasal CPAP or BPAP, although problems with compliance make surgical treatment preferable in some cases. Although UPPP eliminates sleep apnea only in a minority of patients, combining UPPP with maxillofacial procedures appears to improve outcomes. Other treatments such as the use of dental appliances or medications, weight loss, and positional therapy may be useful as adjunctive therapy for moderate to severe OSAS or as primary treatments for UARS or mild OSAS.

Adult↗
PubMed1996

Central sleep apnea.

A central sleep apnea is the absence of respiratory effect, and, thus, the absence of airflow during sleep. Central hypopnea, a related disorder, is also discussed. The sensory component of central sleep apnea; defects involving the integrative and executive neurons; non-neurologic causes of central sleep apneas, including chronic obstructive pulmonary disease and congestive heart failure; diagnosis; treatment; and other topics are reviewed in detail.

Airway Resistance↗
PubMed1996

Cognitive function in patients with sleep apnea after acute nocturnal nasal continuous positive airway pressure (CPAP) treatment: sleepiness and hypoxemia effects.

Patients with sleep apnea are typically hypersomnolent during the daytime and may demonstrate higher order cognitive dysfunction. A persistent problem in interpreting impaired neuropsychological test performance in such patients is whether the observed deficits can be explained wholly by impaired vigilance. We examined 37 sleep apnea patients prior to and immediately subsequent to successful sleep apnea treatment with nasal continuous positive airway pressure (CPAP). Patients were evaluated immediately after morning awakening in the sleep lab. A brief neuropsychological evaluation, was administered at that time. Following this, alertness was measured with a 30-min polysomnographically determined sleep latency test. Both test (approximately 50 min in duration) were performed once following a baseline (diagnostic) night in the sleep lab and once in the morning following a CPAP (therapeutic) night in the lab. Subgroup analyses indicted that while vigilance impairment can account for some of the decreased test performance seen in sleep apnea (auditory verbal learning) the effects of severe nocturnal hypoxemia appear to affect other function (sustained attention in repetitive arithmetic calculations) that were not easily modified by treatment. Thus, performance on the recall trial of the Rey Auditory Verbal Learning Test increased from pre-CPAP to post-CPAP for the increased alertness group but decreased significantly for the decreased alertness group. On the Wilkinson Addition Test, non-hypoxemic patients showed statistically significant improvement in problems correctly solved from pre-CPAP to post-CPAP, but the hypoxemic patients showed only a marginal increase. These results are compatible with other studies suggesting that patients having sleep apnea may incur deficits as a result of both decreased vigilance and hypoxemia, and that at least some of these deficits are immediately reversible.

Adult↗
PubMed1996

Overestimation of sleep latency by patients with suspected hypersomnolence.

The latency to sleep onset has been reported to be overestimated by chronic insomniacs. Observing that some patients evaluated for suspected hypersomnolence complain of insomnia and others fail to report that they are sleepy, we wondered whether overestimation of sleep latency could be occurring in these subjects as well. Since polysomnography (PSG) only provides one sleep onset with which to assess a patient's estimation, we investigated the use of the multiple sleep latency test (MSLT) for this purpose. Among 147 patients who had an MSLT, 137 of whom had a preceding PSG, overestimation of sleep latency occurred on 78% and 74% of the respective tests. The magnitude of overestimation averaged 3 minutes and 27 minutes, respectively, and was not dependent on diagnosis. Subjects who had reported a history of difficulty falling asleep, compared to those who did not, tended to show equivalent objective sleep latencies, longer subjective nocturnal sleep latencies and less overall accuracy in their estimates. Those who denied having a problem with excessive daytime sleepiness (EDS) showed objective sleep latencies nearly identical to those who complained of EDS but had only a trend toward higher overestimation on the MSLT. Overestimation of sleep latency is therefore more readily part of an explanation for why hypersomnolent patients sometimes complain of insomnia than it is for failure to recognize EDS. The MSLT as well as nocturnal recordings can provide data with which to assess overestimation of sleep latency.

Adult↗