Search PubMed⌕ Search

Biomedical subjects

J Montplaisir

Publications and source records attributed to J Montplaisir.

At least 19 recordsLinked to original sources
PubMed2006

Assessing whole brain perfusion changes in patients with REM sleep behavior disorder.

OBJECTIVE: To investigate the regional cerebral perfusion in patients with idiopathic REM behavior disorder (RBD) in order to establish the topography of networks involved. METHODS: We performed cerebral blood flow evaluation using (99m)Tc-Ethylene Cysteinate Dimer (ECD) SPECT on eight patients with polysomnographically confirmed RBD and nine age-matched controls. Comparisons were made using SPM2. RESULTS: We found increased perfusion in the pons and putamen bilaterally and in the right hippocampus. In addition, we observed a decreased perfusion in frontal (Brodmann area [BA] 4, 6, 10, 43, 44, 47 bilaterally and left BA 9, 46) and temporo-parietal (BA 13, 22, 43 bilaterally and left BA 7, 19, 20, 21, 39, 40, 41, 42) cortices. CONCLUSION: Perfusional abnormalities in patients with REM behavior disorder were located in the brainstem, striatum, and cortex. These abnormalities are consistent with the anatomic metabolic profile of Parkinson disease.

Aged↗
PubMed2006

Long-term treatment with pramipexole in restless legs syndrome.

The aim of the present study was to look at the long-term efficacy and side effects profiles of pramipexole in a large cohort of drug naïve patients with regard to dopaminergic medications. In all, 195 consecutive restless legs syndrome (RLS) patients who were prescribed pramipexole more than 1 year previously, agreed to undergo a telephone interview to assess both the efficacy and side effects of pramipexole. Forty-three patients had discontinued pramipexole: 20 because of side effects, six because of a lack of efficacy, six for both and 11 for other reasons. Patients who continued pramipexole for more than 1 year (n = 152) reported a mean decrease in RLS symptoms severity of 80.9% (SD = 19.6%). At the onset of treatment, the most common side effects were nausea (30%), tiredness (9%), dizziness (8%), headache (4%), insomnia (3%), dry mouth (2%), difficulty to concentrate (1.3%) and sleepiness (0.7%), At 30 months, most patients (n = 124/152; 81.6%) reported an absence of side effects of pramipexole. None of the adverse effects occurred in more than 5% of patients at follow-up. The present study confirms, in a large cohort of unselected patients, that pramipexole is effective and safe in the long-term treatment of RLS.

Adult↗
PubMed2004

Association between waking EEG slowing and REM sleep behavior disorder in PD without dementia.

OBJECTIVE: To compare nondemented patients with Parkinson's disease (PD) with and without REM sleep behavior disorder (RBD) to healthy controls on quantitative EEG characteristics for both wakefulness and REM sleep. METHODS: Fifteen patients with PD (7 patients with polysomnographic-confirmed RBD [PD-RBD] and 8 patients without RBD [PD-NRBD]) and 15 healthy control subjects were studied. Each subject underwent a quantitative EEG analysis of both wakefulness and REM sleep. RESULTS: During wakefulness, patients with PD-RBD showed a higher theta power in frontal, parietal, temporal, and occipital regions in comparison to patients with PD-NRBD and control subjects. Moreover, a slowing of the dominant occipital frequency was observed only in patients with PD-RBD (p < 0.02). Patients with PD-NRBD did not present any slowing of the EEG. No between-group difference in quantitative REM sleep EEG was observed. CONCLUSIONS: This study demonstrates that the EEG slowing reported during wakefulness in nondemented patients with PD is strongly related to the presence of RBD.

Aged↗
PubMed2004

Effect of age on MSLT results in patients with narcolepsy-cataplexy.

OBJECTIVE: To measure the effect of age on Multiple Sleep Latency Test (MSLT)characteristics, sleep latency, and number of sleep-onset REM periods (SOREMP) in two large populations of narcoleptic patients with similar genetic backgrounds. METHODS: Clinical and polygraphic information on the severity of the condition was obtained on 236 well-defined narcolepsy-cataplexy-human leukocyte antigen DR2-positive patients from Montpellier (France) and on 147 similar patients from Montreal (Canada). RESULTS: The results show a progressive decrease in the number of SOREMP with age and a progressive increase in the mean sleep latency on the MSLT as a function of age. This finding is also related to the severity of cataplexy as assessed from the clinical history with a progressive decrease in the frequency of cataplexy attacks with age. These results may reflect the progressive increase in sleep latency seen in normal aging and suggest that clinical improvement might be due to changes in the neural mechanisms responsible for SOREMP, which may weaken with age. CONCLUSIONS: The progressive decrease in the number of SOREMP and increase in the mean sleep latency on the MSLT as a function of age suggest that the current criteria used for diagnosis may be too stringent in older patients. The major influence of age on MSLT results should therefore be taken into account when diagnosing a narcoleptic patient.

Adolescent↗
PubMed2003

The effects of pramipexole in REM sleep behavior disorder.

The authors evaluated the effects of pramipexole, a dopaminergic D2-D3 receptor agonist, on eight patients with idiopathic REM sleep behavior disorder. Five patients reported a sustained reduction in the frequency or intensity of sleep motor behaviors, which was confirmed by video recording, although no change was observed for the percentage of phasic EMG activity during REM sleep. Surprisingly, a decrease in the percentage of time spent with REM sleep muscle atonia was observed with treatment. The treatment did not modify the indexes of periodic leg movements.

Aged↗
PubMed2003

Age and gender effects on heart rate activation associated with periodic leg movements in patients with restless legs syndrome.

OBJECTIVE: Periodic leg movements during sleep (PLMS) are often associated with electroencephalographic (EEG) changes, such as microarousals (MA), and with heart rate (HR) variations. The aim of the present study was to evaluate the effects of age and gender on HR changes associated with PLMS in restless legs syndrome (RLS) patients. METHODS: Forty-two RLS patients underwent one night of polysomnographic recordings. They were divided into 3 groups of 14 subjects (7 women and 7 men) according to age, i.e. young (25-40 years), middle-aged (41-55 years) and elderly (56-71 years) patients. The RR interval was calculated for 5 intervals before and 15 intervals after the onset of 50 PLMS in each patient. RESULTS: PLMS were associated with HR changes characterized by a tachycardia followed by a bradycardia. However, a reduction in the tachycardia and the bradycardia was observed with age. Moreover, women showed a higher amplitude in the bradycardia than men. No age or gender difference was found for MA index and duration. CONCLUSIONS: This study showed age and gender differences in the magnitude of the HR changes associated with PLMS. The knowledge of HR variations during sleep, including rapid HR changes associated with sleep events such as PLMS or MA, may be helpful in understanding the potential mechanisms involved in the increased cardiac risk observed in elderly.

Adult↗
PubMed2002

Periodic leg movements in REM sleep behavior disorder and related autonomic and EEG activation.

OBJECTIVE: To assess the frequency of periodic leg movements (PLM) in idiopathic REM sleep behavior disorder (RBD) and to analyze their polysomnographic characteristics and associated autonomic and cortical activation. BACKGROUND: PLM during sleep (PLMS) and wakefulness (PLMW) are typical features of restless legs syndrome (RLS), but are also frequently observed in patients with RBD. METHODS: Forty patients with idiopathic RBD underwent one night of polysomnographic recording to assess PLMS frequency. PLM features, PLMS-related cardiac activation during stage 2 sleep, and EEG changes were analyzed in 15 of these patients with RBD. Results were compared with similar data obtained in 15 sex- and age-matched patients with primary RLS. RESULTS: Twenty-eight (70%) of 40 patients with RBD showed a PLMS index greater than 10. No between-group differences were found in sleep architecture or indexes of PLMW and PLMS during non-REM sleep, but a trend for a higher PLMS index during REM sleep was found in patients with RBD. PLM mean duration and interval in the two conditions were similar. A transient tachycardia followed by a bradycardia was observed in close association with every PLMS in both groups, but the amplitude of the cardiac activation was significantly reduced in patients with RBD. In addition, significantly fewer PLMS were associated with microarousal in this condition. CONCLUSIONS: Periodic leg movements are very common in idiopathic RBD, occurring in all stages of sleep, especially during REM sleep. In idiopathic RBD, the reduction of cardiac and EEG activation associated with PLMS suggests the presence of an impaired autonomic and cortical reactivity to internal stimuli.

Aged↗
PubMed2002

REM sleep behavior disorder and REM sleep without atonia in Parkinson's disease.

OBJECTIVE: To determine the frequency of REM sleep behavior disorder (RBD) among patients with PD using both history and polysomnography (PSG) recordings and to further study REM sleep muscle atonia in PD. BACKGROUND: The reported occurrence of RBD in PD varies from 15 to 47%. However, no study has estimated the frequency of RBD using PSG recordings or analyzed in detail the characteristics of REM sleep muscle atonia in a large group of unselected patients with PD. METHODS: Consecutive patients with PD (n = 33) and healthy control subjects (n = 16) were studied. Each subject underwent a structured clinical interview and PSG recording. REM sleep was scored using a method that allows the scoring of REM sleep without atonia. RESULTS: One third of patients with PD met the diagnostic criteria of RBD based on PSG recordings. Only one half of these cases would have been detected by history. Nineteen (58%) of 33 patients with PD but only 1 of 16 control subjects had REM sleep without atonia. Of these 19 patients with PD, 8 (42%) did not present with behavioral manifestations of RBD, and their cases may represent preclinical forms of RBD associated with PD. Moreover, the percentage of time spent with muscle atonia during REM sleep was lower among patients with PD than among healthy control subjects (60.1% vs 93.2%; p = 0.003). CONCLUSIONS: RBD and REM sleep without atonia are frequent in PD as shown by PSG recordings.

Aged↗
PubMed2002

Evidence for a genetic association between monoamine oxidase A and restless legs syndrome.

BACKGROUND: Impairment in the central dopaminergic system has been consistently suggested as an etiologic factor in restless legs syndrome (RLS). OBJECTIVE: To investigate a possible role for the MAOA and MAOB genes in RLS using a population-based association study. METHODS: In addition to a dinucleotide repeat located within the second intron of the MAOB gene, a functional variable number of tandem repeat (VNTR) polymorphism recently identified in the MAOA gene promoter region was examined, using 96 extensively characterized patients and 200 control subjects matched for ethnic background. The relationship between variation at these loci and several clinical features was also considered. RESULTS: Pertaining to the MAOA gene, females with the high activity allele had a greater risk (OR: 2.0; 95% CI: 1.06 to 3.77) of being affected with RLS than females carrying the low activity alleles. The authors did not observe this association among the male subjects (OR: 0.98; 95% CI: 0.31 to 3.14). Interestingly, females carrying the high transcription alleles showed a longer sleep onset latency (U = 163.5; p = 0.015) and exhibited a higher movement index during the Suggested Immobilization Test (Student's t-test = -2.02; p = 0.048). No differences were observed regarding the MAOB gene in our sample. CONCLUSIONS: The high activity allele of the MAOA gene may represent a modifying factor involved in the severity of RLS manifestations in females.

Adult↗
PubMed2002

Age difference in heart rate changes associated with micro-arousals in humans.

OBJECTIVES: Heart rate (HR) is known to change in association to micro-arousals (MA) during sleep. The aim of the present study was to evaluate the effect of age on HR variations associated with MA. METHODS: Thirty-two healthy subjects underwent one night of polysomnographic recording. They were divided into two groups of 16 subjects according to age i.e. young (20-35 years) and middle-aged (50-65 years). The R-R intervals were calculated for 11 heart beats (10 intervals) before and 15 heart beats after the onset of MA. RESULTS: HR changes associated with MA were characterized by a tachycardia followed by a bradycardia in both young- and middle-aged subjects. However, middle-aged subjects showed a significant reduction in the amplitude of both tachycardia and bradycardia as compared to young subjects. CONCLUSIONS: This study revealed an age-related reduction in the amplitude of the HR changes associated with MA. These results may reflect a decline in parasympathetic functions and a higher risk of cardiovascular diseases with advancing age.

Adult↗
PubMed2002

[Rapid-eye-movement sleep disorders in Parkinson's disease].

During the past 10 years, there has been an increasing interest in the study of rapid-eye-movement (REM) sleep in neurodegenerative diseases and more particulary in Parkinson's disease (PD). This interest is justified by the strong association observed between these diseases and REM sleep behavior disorder (RBD). In the first section of this paper, a critical review of the literature on the presence of REM sleep disorders in PD is presented. Studies that show an association between PD and RBD are reviewed. Studies that report the presence of other REM sleep disorders in PD (short latency, abnormal length and/or proportion of REM sleep, increasing occurrence of hallucinations) are then discussed. Limitations of the criteria proposed by Rechtschaffen et Kales (1968) for the quantification of REM sleep are also presented. Some authors believe that dopaminergic (DA) agents used in the treatment of PD (levodopa, bromocriptine, pergolide, pramipexole and selegiline) could be a responsable factor for the occurence of REM sleep disorders observed in this disease. The literature concerning the impact of these DA agents on human REM sleep is therefore critically reviewed. It is concluded that DA agents cannot explain on their own the presence of REM sleep disorders in PD. Other causes, among which the disturbance of some neurochemical systems linked to the neuropathological process of the disease, must be considered in order to explain these REM sleep disorders. In the second section of this paper, we present the different pathophysiological hypotheses proposed to explain REM sleep disorders in PD, such as a dysfunction of the cholinergic, noradrenergic, serotonergic, dopaminergic or GABAergic neurons. Emphasis is placed on the role of cholinergic neurons of the pedunculopontine and laterodorsal tegmental nuclei, structures shown to be particularly impaired in PD. Neurophysiological, neuroanatomical and neuropharmacological studies demonstrate that these neurons are strongly implicated in the different REM sleep parameters (muscular atonia, electroencephalographic desynchronisation, ponto-geniculo-occipital spikes). Finally, future research directions are proposed.

Antiparkinson Agents↗
PubMed2001

Age at onset of narcolepsy in two large populations of patients in France and Quebec.

BACKGROUND: Narcolepsy usually starts around adolescence; however, there is great variability in the clinical presentation of narcolepsy. OBJECTIVE: To determine the age at onset in conjunction with severity of narcoleptic symptoms in two large populations of narcoleptic patients with a similar genetic background. METHODS: Information on age at onset and severity of the condition was obtained in 317 patients with well-defined narcolepsy-cataplexy from Montpellier (France) and in 202 from Montreal (Canada). RESULTS: The mean age at onset was 23.4 years in Montpellier and 24.4 in Montreal. The age at onset was bimodal in two independent patient populations: a first peak occurring at 14.7 years, and a second peak occurring at 35. Age at onset clearly differentiates patients with a positive family history of narcolepsy (early onset) from those without a family history. Other clinical and polygraphic findings may indicate that young age at onset is associated with increased severity of the condition (higher frequency of cataplexy and decreased mean sleep latency on the Multiple Sleep Latency Test). CONCLUSION: Bimodal distribution of age at onset of narcolepsy was found in two independent patient populations. Our data suggest that age at onset is genetically determined.

Adolescent↗
PubMed2001

Identification of a major susceptibility locus for restless legs syndrome on chromosome 12q.

Restless legs syndrome (RLS) is a neurological disorder characterized by leg paresthesia associated with an irresistible urge to move that often interferes with nocturnal sleep, leading to chronic sleep deprivation. To map genes that may play a role in the vulnerability to RLS, a genomewide scan was conducted in a large French-Canadian family. Significant linkage was established on chromosome 12q, for a series of adjacent microsatellite markers with a maximum two-point LOD score of 3.42 (recombination fraction.05; P=6x10(-4); autosomal recessive mode of inheritance), whereas multipoint linkage calculations yielded a LOD score of 3.59. Haplotype analysis refined the genetic interval, positioning the RLS-predisposing gene in a 14.71-cM region between D12S1044 and D12S78. These findings represent the first mapping of a locus conferring susceptibility to RLS.

Canada↗
PubMed2001

Dopaminergic neurotransmission and restless legs syndrome: a genetic association analysis.

In order to examine the genetic substrate of the dopamine hypothesis in restless legs syndrome, we analyzed eight genes coding for receptors and enzymes related to dopaminergic transmission, using a population of 92 patients with restless legs syndrome and 182 controls matched for ethnic background. No significant differences were found in the genotypic or allelic distributions between groups. Furthermore, no effect of the loci examined was observed with stratification using clinical parameters such as age at onset or periodic leg movements during sleep index.

Adult↗
PubMed2001

Sleep spindle characteristics in healthy subjects of different age groups.

OBJECTIVES: Few studies have quantified the various characteristics of sleep spindles (SS) in groups of normal human subjects. The aim of the present study was to look at the effects of age on the number, density, duration, intra-spindle frequency, and periodicity of SS during stage 2 sleep in normal subjects of different age groups. METHODS: Thirty-six healthy subjects participated in the study. They were divided into 6 age groups: 10-19, 20-29, 30-39, 40-49, 50-59 and 60-69 years. RESULTS: The results show that there is a progressive decrease in SS number, density, duration and a progressive increase in intra-spindle frequency with age. These changes occur mainly in the first 4 decades, except for SS number and density, for which the changes seem to continue until the sixth decade. The present study also reveals a clear periodicity of SS in human sleep. SS occur every 3-6 s, and the modal value of inter-spindle intervals increases with aging. CONCLUSIONS: The progressive decrease in the number of SS and slow-wave sleep time with age suggests that SS are part of sleep promoting mechanisms. The negative correlation found between SS density and sleep efficiency in the present study is congruent with the sleep maintenance role of SS.

Adult↗