G Poirier

Université du Québec à Montréal, Montréal, Quebec, Canada

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Publications (14)91.19 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Restless legs syndrome (RLS) is defined by an irresistible need to move associated with leg paresthesia. Two additional features are essential for diagnosis: (1) worsening of symptoms at rest with temporary relief by activity, and (2) worsening of symptoms during the evening and/or during the night. The suggested immobilization test (SIT) has been developed to evaluate the presence of these criteria. This test quantifies leg movements and leg discomfort during a 1-hour period of immobility prior to bedtime. We used the SIT to evaluate the effects of immobility on leg discomfort and leg movements experienced by 19 patients with RLS and 19 control subjects. Results show that immobility significantly worsens both leg discomfort and periodic leg movements (PLM) in patients with RLS but not in controls. Patients with RLS showed a higher leg discomfort score (32.6 +/- 15.1 mm vs. 5.7 +/- 7.9 mm; P < 0.00001), a greater maximum leg discomfort value (63.4 +/- 27.4 mm vs. 13.7 +/- 23.0 mm; P < 0.00001) and a greater PLM index (88.4 +/- 62.6 vs. 10.4 +/- 20.6; P < 0.00004) than control subjects. These results further validate the use of the SIT as a diagnostic and research tool for RLS and confirm the contention of the International RLS study group that RLS symptoms worsen at rest.
    Movement Disorders 02/2002; 17(1):112-5. · 4.56 Impact Factor
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    ABSTRACT: Objective: To evaluate the characteristics of leg movements experienced by patients with the restless legs syndrome (RLS) during wakefulness using the suggested immobilization test (SIT).Methods: Forty patients with primary RLS who showed an index of leg movements greater than 40 during the SIT were selected for these analyses.Results: In general, Coleman's criteria for scoring PLMS were appropriate for scoring leg movements during the SIT. However, a substantial number of leg movements lasted between 5 and 10 s, exceeding Coleman's maximum duration criterion. The other criteria used to score PLMS (i.e. movements separated by 4-90 s and occurring in series of four consecutive movements) allowed detection of more than 90% of all leg movements recorded during the SIT. The distribution of inter-movement intervals (IMI) suggests that a great majority of leg movements recorded during the SIT are periodic, with a modal value of IMI between 11-12 s.Conclusion: Considering that leg movements recorded during the SIT last longer than those occurring during sleep, we recommend using a duration criterion of 0.5-10 s for scoring the former. We also recommend using the same periodicity criteria for the SIT as those used for scoring PLMS.
    Sleep Medicine 08/2001; 2(4):317-321. · 3.49 Impact Factor
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    ABSTRACT: Rhythmic Masticatory Muscle Activity (RMMA) is frequently observed during sleep in normal subjects and sleep bruxers. We hypothesized that some normal subjects exhibit RMMA at a lower frequency than sleep bruxers. Polysomnographic data from 82 normal subjects were compared with data from 33 sleep bruxers. RMMA episodes were defined as three or more consecutive bursts of masseter EMG activity, with or without tooth-grinding. Such episodes were observed in nearly 60% of normal subjects. A lower frequency of episodes was noted in normal subjects than in bruxers. Sleep organization was similar between groups. Bruxers had twice as many masseter muscle bursts per episode and episodes of higher amplitude compared with controls with RMMA. The high prevalence of RMMA observed in normal subjects suggests that this activity is related to certain sleep-related physiological functions, including autonomic activation.
    Journal of Dental Research 03/2001; 80(2):443-8. · 3.83 Impact Factor
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    ABSTRACT: One hundred thirty-three cases of restless legs syndrome (RLS), diagnosed with criteria recently formulated by an international study group, were studied by questionnaire and with all-night polysomnographic recordings. Results show that RLS starts at a mean age of 27.2 years and before age 20 in 38.3% of patients. Symptoms often appear in one leg only and also involve upper limbs in about half of all cases. Most patients (94%) report sleep-onset insomnia or numerous nocturnal awakenings due to RLS symptoms. A strong relationship was found between these complaints and polysomnographic findings; increasing sleep latency and number of awakenings and decreasing sleep efficiency were associated with worsening symptoms. Periodic leg movements in sleep (index > 5 movements/h sleep) were found in 80.2% of patients. This study shows that this percentage is increased when 2 recording nights are considered (most severe score). Eighty patients of 127 (63%) reported the presence of RLS in at least one of their first-degree relatives. In these families, 221 of 568 first-degree relatives (39%) were reported by the patients to be affected with RLS.
    Movement Disorders 01/1997; 12(1):61-5. · 4.56 Impact Factor
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    ABSTRACT: Compared to normal control subjects, patients with primary restless legs syndrome (RLS) have an increased number of K-complexes, followed by bursts of electroencephalographic (EEG) alpha activity-together these are referred to as K-alpha complexes. In the present study, a large proportion of K-alpha complexes was found to be temporally associated with periodic leg movements in sleep. Because many K-alpha complexes precede the onset of movements, they cannot be considered secondary to the movements themselves. The persistence of K-alpha complexes after suppression of leg movements by means of L-DOPA further supports the hypothesis that these EEG events are a primary phenomenon. The results may have clinical implications because a large proportion of RLS patients complain of non-restorative sleep even after treatment with L-DOPA.
    Sleep 05/1996; 19(3):196-9. · 5.10 Impact Factor
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    ABSTRACT: Examined potential relationships between human leukocyte antigens (HLAs), including the DR series, and depression in 19 depressed female patients (mean age 49.9 yrs) and 49 hypersomniac male and female patients (mean age 38.5 yrs). Frequency of HLA-DR5 was significantly increased in both depressed and hypersomniac Ss, providing support for the notion of a possible link between these conditions. Results also suggest that HLA-DR5 antigen may be more frequent in a subgroup of familial and recurrent depressive patients. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
    Biological Psychiatry 04/1990; 27(6):664-6. · 9.25 Impact Factor
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    ABSTRACT: A large proportion of narcoleptic patients have periodic leg movements (PMS) in sleep. The contribution of these movements to the nocturnal sleep disturbance observed in narcoleptics remains a controversial issue. The aim of the present study was to look at the sleep organization of narcoleptic patients before and after suppression of periodic leg movements with L-dopa. L-dopa and a placebo were administered in a double-blind fashion to six narcoleptic patients. Each treatment period lasted 2 weeks and the treatment order was reversed for one-half of the subjects. The effects of L-dopa and placebo were evaluated by polysomnography. A significant reduction of PMS was seen after treatment with L-dopa, but this treatment did not improve sleep organization. On the contrary, L-dopa increased wake time after sleep onset. This result supports the hypothesis that PMS does not play a major role in the nocturnal sleep disruption observed in narcolepsy. It also supports the hypothesis that dopaminergic mechanisms play a role in the physiopathology of PMS.
    Clinical Neuropharmacology 09/1989; 12(4):339-45. · 1.82 Impact Factor
  • J Montplaisir, G Poirier
    Neurology 07/1987; 37(6):1089. · 8.30 Impact Factor
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    ABSTRACT: Seventy white patients with a diagnosis of MS and typed for their HLA-A, B, C, and DR were studied. A clinical interview and a questionnaire were used to evaluate the presence of narcoleptic symptoms. The prevalence of sleep attacks, cataplexy, and sleep paralysis was significantly elevated among these patients. However, no difference was seen between DR2 and non-DR2 subjects with regard to the incidence of narcoleptic symptoms. Nine DR2 patients complaining of both sleep attacks and cataplexy were studied in the sleep laboratory for five consecutive naps, but no polygraphic evidence of narcolepsy was found.
    Neurology 05/1987; 37(4):693-5. · 8.30 Impact Factor
  • JAMA The Journal of the American Medical Association 06/1986; 255(17):2295-6. · 29.98 Impact Factor
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    ABSTRACT: Seven patients suffering from restless legs syndrome (RLS) and periodic movements in sleep (PMS) were investigated before and after treatment with L-Dopa. The effect of treatment was evaluated by polysomnography, structured interviews, and daily questionnaires. Sleep organization and subjective complaints improved during treatment with 100 to 200 mg of L-Dopa. Polysomnographic recordings also revealed a significant decrease of periodic leg movements during the first third of the night and a rebound during the last third. These results and previous biochemical findings raise the hypothesis that RLS and PMS may both result from reduced dopaminergic activity in the CNS, perhaps resulting from decreased sensibility of postsynaptic receptors.
    Clinical Neuropharmacology 02/1986; 9(5):456-63. · 1.82 Impact Factor
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    ABSTRACT: Twenty-three narcoleptic subjects participated in a single-blind drug study with placebo-viloxazine hydrochloride (100 mg/day). One woman discontinued the study because of nausea and headaches during the treatment period. The remaining 22 subjects were polygraphically monitored during baseline, The remaining 22 subjects were polygraphically monitored during baseline, placebo intake, viloxazine treatment, and placebo intake following 48 h of drug withdrawal. Symptoms and side effects were evaluated subjectively and objectively. Except for the subject who discontinued the study, viloxazine was well tolerated, particularly in elderly subjects. The drug had an inhibitory effect on REM sleep, cataplexy, and other auxiliary symptoms. While there is no objective evidence that it heightens alertness, patients reported fewer sleep attacks.
    Sleep 02/1986; 9(1 Pt 2):275-9. · 5.10 Impact Factor
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    ABSTRACT: Several studies have shown familial incidence of narcolepsy and idiopathic central nervous system (CNS) hypersomnia. HLA antigen studies performed in mongoloid and caucasoid narcoleptic patients on the A, B, and C loci have yielded conflicting results. The aim of this study is to document a possible association between the HLA system, including the DR locus and excessive daytime somnolence. Thirty-one narcoleptic patients and 10 idiopathic hypersomniac patients were selected and typed for 54 HLA antigens. A family with narcoleptic members in 3 generations was also studied. HLA-DR2 was found in 100% of narcoleptic patients. The frequency of HLA-A3 and B7, which are in linkage disequilibrium with DR2 was also increased in this group. Idiopathic hypersomniac patients showed an increase of HLA-Cw2, DR5, and B27, three antigens known to be in linkage disequilibrium. In the family study, narcoleptic patients were also HLA-DR2; moreover, 3 subjects, one of whom was narcoleptic, were HLA-DR2 as a result of recombination (i.e., genetic crossing-over). These results locate the hypothetic gene associated with narcolepsy more precisely, and indicate that narcolepsy and idiopathic CNS hypersomnolence are two different entities.
    Sleep 02/1986; 9(1 Pt 2):153-8. · 5.10 Impact Factor
  • L'unión médicale du Canada 01/1986; 114(12):974-6.

Publication Stats

755 Citations
91.19 Total Impact Points

Institutions

  • 1997
    • Université du Québec à Montréal
      Montréal, Quebec, Canada
  • 1990
    • Université de Montréal
      • Department of Psychiatry
      Montréal, Quebec, Canada
  • 1989
    • Hôpital du Sacré-Coeur de Montréal
      • Center for Advanced Research in Sleep Medicine
      Montréal, Quebec, Canada