Tobacco use and reported bruxism in young adults: a nationwide Finnish Twin Cohort Study.

INTRODUCTION: Higher levels of smoking, leading to increased levels of nicotine and dopamine release, may be more strongly related to bruxism, although this relationship has remained unclear. Thus, the aim of the present study was to investigate the possible effect of cumulative tobacco use on bruxism in a large sample of young adults. METHODS: The material of the present study derives from the FinnTwin16, which consists of five birth cohorts born in 1975-1979. A total of 3,124 subjects (mean age 24 years, range 23-27 years) provided data in 2000-2002 on frequency of bruxism and tobacco use. Multinomial logistic regression was used to explore the relationships of frequency of bruxism with smoking and smokeless tobacco use while controlling covariates (alcohol intoxication, alcohol problems [Rutgers Alcohol Problem Index, RAPI], illicit drug use, psychological distress [General Health Questionnaire], and coffee use). RESULTS: Based on subjective response and multivariate analyses, weekly bruxers were more than two times more likely to report heavy smoking than never bruxers (odds ratio [OR] 2.5, 95 % CI 1.8-3.4). The significant association between heavy smoking and bruxism held when the effects of other tobacco use and multiple covariates were controlled. In addition, the use of smokeless tobacco emerged as an independent risk factor for bruxism. DISCUSSION: Given the observed associations with both heavy smoking and smokeless tobacco and a dose-response relationship, the present results support our hypothesis of a link between nicotine intake and bruxism.

Bruxism is associated with nicotine dependence: a nationwide Finnish twin cohort study.

OBJECTIVES: To investigate the association of smoking with bruxism while controlling for genetic and environmental factors using a co-twin-control design. Especially, the role of nicotine dependence was studied in this context. METHODS: The material derives from the Finnish Twin Cohort consisting of 12,502 twin individuals who responded to a questionnaire in 1990 (response rate of 77%). All were born in 1930-1957, the mean age being 44 years. The questionnaire covered 103 multiple choice questions, 7 dealing with tobacco use and 22 with sleep and vigilance matters, including perceived bruxism. In addition, a subsample derived from the Nicotine Addiction Genetics Finland Study containing 445 twin individuals was studied. RESULTS: In age- and gender-controlled multinomial logistic regression, both monthly and rarely reported bruxism associated with both current cigarette smoking (odds ratio [OR] = 1.74 and 1.64) and former cigarette smoking (OR = 1.64 and 1.47). Weekly bruxism associated with current smoking (OR = 2.85). Current smokers smoking 20 or more cigarettes a day reported weekly bruxism more likely (OR = 1.61-1.97) than those smoking less. Among twin pairs (N = 142) in which one twin was a weekly bruxer and the cotwin a never bruxer, there were 13 monozygotic pairs in which one twin was a current smoker and the other twin was not. In all cases, the bruxer was the smoker (p = .0003). Nicotine dependence associated significantly with bruxism. CONCLUSIONS: Our twin study provides novel evidence for a possible causal link between tobacco use and bruxism among middle-aged adults. Nicotine dependence may be a significant predisposing factor for bruxism.

Awareness of tooth grinding and clenching from adolescence to young adulthood: a nine-year follow-up.

How bruxism develops from adolescence to early adulthood remains unclear. A previous database was revisited to evaluate the natural course of self-reported tooth grinding and clenching among young Finns aged 14-23 using four assessments. Overall, the self-reported frequencies of both grinding and clenching increased during the examination period: from 13.7% to 21.7% and from 9.2% to 14.8%, respectively. There were significant increases (without a statistically significant difference between genders) in both grinding (P = 0.002) and clenching (P = 0.015) between 15 and 23 years. A significant rise in grinding between 18 and 23 years was also found (P = 0.011). It is concluded that self-reported bruxism increases from adolescence to young adulthood. Moreover, there are large differences between individuals, and fluctuations may occur in the natural course of bruxism.

Prevalence of narcolepsy with cataplexy in Norway.

OBJECTIVES: Narcolepsy is a lifelong disabling disorder that may be alleviated by relevant treatment. Patients frequently report 10-15 years from the first symptoms to the time they get the diagnosis and treatment can be started. In order to offer a sufficient diagnostic and therapeutic service to this patient group, a reliable estimation of the prevalence of the disorder is important. A study of the prevalence of narcolepsy with cataplexy in Norway was therefore undertaken. MATERIALS AND METHODS: The Ullanlinna Narcolepsy scale (UNS) was sent to 14548 randomly selected Norwegians between 20 and 60 years. Additionally, the study included telephone interviews and clinical evaluation of responders with >or=14 points on the UNS, and in those with suspected narcolepsy, polygraphic sleep recordings and human leucocyte antigen (HLA)-typing. RESULTS: A total of 8992 responders answered the questionnaire (response rate 61.8%), 267 had >or=14 points on the UNS, 156 were interviewed and 15 had sleep recordings. In two HLADQB1*0602-positive patients sleep recordings were compatible with narcolepsy. CONCLUSIONS: The results indicate a prevalence of 0.022% and approximately 1000 patients with narcolepsy with cataplexy in Norway.

Bruxism and sleep efficiency measured at home with wireless devices.

The present study comprised 101 (48 men) employees of the Finnish Broadcasting Company with or without irregular shift work, but all with a work week of five shifts in a row followed by 2 days off. The mean age of the subjects was 41.0 years (SD = 9.9). The BiteStrip, a single-use disposable EMG device was used for one night during the work week to detect sleep bruxism. The Actiwatch Plus actigraph was worn on the non-dominant wrist for the entire week to evaluate sleep. Total sleep time and fragmentation index, the latter as a measure of sleep efficiency was calculated for the present study. The BiteStrip scores among the participants were: 0- no bruxism: 52.2% (according to the manufacturer, comparable to a sleep laboratory bruxism count of up to 39 over 5 h), 1- mild: 29.3% (40-74 counts), 2- moderate: 12.0%: (75-124 counts) and 3- severe: 6.5% (>125 counts). Severe bruxers slept less during the work week than non-bruxers (P = 0.009), but severe bruxers slept slightly more than non-bruxers during days off. The group means of the sleep fragmentation index decreased from start towards the middle of the work week and increased during days off (P = 0.016). The levels of the fragmentation indices were consistently higher in accordance with bruxism severity (P = 0.013). It was concluded that bruxism has a coherent relationship with sleep efficiency and it can be detected at home with a low cost device.

Effects of alertness management training on sleepiness among long-haul truck drivers: A randomized controlled trial.

Education is a frequently recommended remedy for driver sleepiness in occupational settings, although not many studies have examined its usefulness. To date, there are no previous on-road randomized controlled trials investigating the benefits of training on sleepiness among employees working in road transport. To examine the effects of an educational intervention on long-haul truck drivers' sleepiness at the wheel, amount of sleep between work shifts, and use of efficient sleepiness countermeasures (SCM) in association with night and non-night shift, a total of 53 truck drivers operating from southern Finland were allocated into an intervention and a control group using a stratified randomization method (allocation ratio for intervention and control groups 32:21, respectively). The intervention group received a 3.5-hour alertness management training followed by a two-month consultation period and motivational self-evaluation tasks two and 4-5 months after the training, while the control group had an opportunity to utilize their usual statutory occupational health care services. The outcomes were measured under drivers' natural working and shift conditions over a period of two weeks before and after the intervention using unobtrusive data-collection methods including the Karolinska Sleepiness Scale measuring on-duty sleepiness, a combination of actigraphy and a sleep-log measuring sleep between duty hours, and self-report questionnaire items measuring the use of SCMs while on duty. The data analysis followed a per-protocol analysis. Results of the multilevel regression models showed no significant intervention-related improvements in driver sleepiness, prior sleep, or use of SCMs while working on night and early morning shifts compared to day and/or evening shifts. The current study failed to provide support for a feasible non-recurrent alertness-management training being effective remedy for driver sleepiness in occupational settings. These results cannot, however, be interpreted as evidence against alertness management training in general but propose that driver education is not a sufficient measure as such to alleviate driver sleepiness.

Sleepiness, sleep, and use of sleepiness countermeasures in shift-working long-haul truck drivers.

Driver sleepiness is a prevalent phenomenon among professional drivers working unconventional and irregular hours. For compromising occupational and traffic safety, sleepiness has become one of the major conundrums of road transportation. To further elucidate the phenomenon, an on-road study canvassing the under-explored relationship between working hours and sleepiness, sleep, and use of sleepiness countermeasures during and outside statutory rest breaks was conducted. Testing the association between the outcomes and working hours, generalized estimating equations models were fitted on a data collected from 54 long-haul truck drivers (mean 38.1 ± 10.5 years, one female) volunteering in the 2-week study. Unobtrusive data-collection methods applied under naturalistic working and shift conditions included the Karolinska Sleepiness Scale (KSS) measuring sleepiness, a combination of actigraphy and sleep-log measuring sleep, and self-report questionnaire items incorporated into the sleep-log measuring the use of sleepiness countermeasures during and outside statutory rest breaks. Drivers' working hours were categorized into first and consecutive night, morning and day/evening shifts based on shift timing. The results reveal severe sleepiness (KSS≥7) was most prevalent on the first night (37.8%) and least on the morning (10.0%) shifts. Drivers slept reasonably well prior to duty hours, with main sleep being longest prior to the first night (total sleep time 7:21) and shortest prior to the morning (total sleep time 5:43) shifts. The proportion of shifts whereby drivers reported using at least one sleepiness countermeasure outside statutory rest breaks was approximately 22% units greater for the night than the non-night shifts. Compared to the day/evening shifts, the odds of severe sleepiness were greater only on the first night shifts (OR 6.4-9.1 with 95% confidence intervals, depending on the statistical model), the odds of insufficient daily sleep were higher especially prior to the consecutive night shifts (OR 3.5 with 95% confidence intervals), and the odds of using efficient sleepiness countermeasures outside statutory rest breaks were greater on the first as well as consecutive night shifts (OR 4.0-4.6 with 95% confidence intervals). No statistically significant association was found between shift type and use of efficient sleepiness countermeasures during statutory rest breaks. In all, the findings demonstrate marked differences in the occurrence of severe sleepiness at the wheel, sleep preceding duty hours, and the use of sleepiness countermeasures between different shift types. In addition, although drivers slept reasonably well in connection with different shift types, the findings imply there is still room for improvement in alertness management among this group of employees.

Selegiline in the treatment of narcolepsy.

We treated 17 narcolepsy patients in a placebo-controlled, double-blind, crossover trial with 10-, 20-, 30-, and 40-mg daily doses of selegiline, a monoamine oxidase inhibitor widely used in Parkinson's disease. There was a dose-dependent as well as a statistically and clinically significant improvement in narcoleptic symptoms and polygraphic measures. At 40 mg, there was a 36% reduction in the number of daytime sleep episodes and a 34% reduction in their duration (compared with placebo, mean values). The number of excessive sleepiness episodes decreased by 43%, and the duration decreased by 47%. The number of cataplectic attacks was reduced by 89%. On the multiple sleep latency test, the REM sleep latency increased from 5.0 to 13.3 minutes, and the number of sleep-onset REM periods decreased from 3.1 to 0.6. Sleep (S1) latency was not changed. No intolerable adverse events occurred. The effective dose range was 20 to 40 mg, requiring a low-tyramine diet, which was easy to maintain. In conclusion, selegiline alleviates both main symptoms of narcolepsy--the abnormal sleep tendency and cataplexy. Thus, treatment with selegiline makes it possible to avoid polypharmacy and to use a potent stimulant without known addiction risk.

Prevalence and genetics of sleepwalking: a population-based twin study.

We investigated the prevalence of sleepwalking using a well defined population previously used for epidemiologic investigations: the Finnish Twin Cohort. The study population consisted of 11,220 subjects aged 33 to 60 years, and it included 1,045 monozygotic and 1,899 dizygotic twin pairs. Questions on the frequency of sleepwalking were asked separately for occurrence in childhood and adulthood. Childhood sleepwalking was significantly more frequent in women ("often" in 2.8% of women and 2.0% of men and "sometimes" in 6.9% of women and 5.7% of men). As adults, sleepwalking had occurred in 3.9% of men and in 3.1% of women, and it was reported "weekly" in 0.4% for both genders. There was no significant difference in frequency between monozygotic and dizygotic twin individuals, either in childhood or adulthood. For sleepwalking in childhood the probandwise concordance rate was 0.55 for monozygotic and 0.35 for dizygotic pairs, and for adults, 0.32 for monozygotic, and 0.06 for dizygotic pairs. Those who reported never having walked in their sleep in childhood did so as adults rarely (0.6%), both men and women. Those who reported walking in their sleep often or sometimes in childhood did so as adults for 24.6% of men and for 18.3% of women. Of adult men sleepwalkers 88.9% had a positive history of sleepwalking in childhood, and in women, 84.5%. The proportion of total phenotypic variance attributed to genetic influences was 66% in men and 57% in women in childhood sleepwalking, and 80% in men and 36% in women in adult sleepwalking. Our results show that there are substantial genetic effects in sleepwalking in both childhood and adulthood.

An FDOPA PET study in patients with periodic limb movement disorder and restless legs syndrome.

The authors investigated nine drug-naive patients with periodic limb movement disorder and restless legs syndrome (PLMD-RLS) and 27 healthy controls with PET using 6-[18F]fluoro-L-dopa (FDOPA). In the patients, the FDOPA uptake (Ki(occ)) in the caudate nucleus was 88% and in the putamen 89% of the control mean values. This equal affection of the caudate and the putamen differs, for example, from the dopaminergic dysfunction in Parkinson's disease, which affects the putamen earlier and more severely than the caudate. The current results indicate mild nigrostriatal presynaptic dopaminergic hypofunction in PLMD-RLS.

Positron emission tomography study of human narcolepsy: no increase in striatal dopamine D2 receptors.

We investigated dopamine D2 receptors in the caudate nucleus and putamen with positron emission tomography in seven patients with narcolepsy and seven healthy controls by using [11C]raclopride as a ligand. We applied an equilibrium method and Scatchard principle to give a quantitative estimation of the number (Bmax) and dissociation constant (Kd) of the receptors. Both the Bmax and Kd were within the normal range in the caudate nucleus and putamen in narcoleptic patients. We found no evidence for increased D2 receptor binding in narcolepsy.

Limits of self-report in assessing sleep terrors in a population survey.

Sleep terrors are less frequent compared to other parasomnias, and there are no prevalence studies on adults. We performed a questionnaire study in a well-defined population-based sample, the Finnish Twin Cohort. The study population consisted of 11,220 subjects aged 33-60 years, responding to questions on the frequency of sleep terrors in childhood and as adults. In the first questionnaire about 9% reported sleep terrors often or sometimes in childhood, and 3.5% at least once monthly as adults. However, in a second more-detailed questionnaire, only 1% of those with at-least-monthly attacks in adulthood presented with features compatible with the minimal diagnostic criteria for sleep terrors of the International Classification of Sleep Disorders. There was also a strong correlation between current occurrence of nightmares and the report of sleep terrors. Although a clinically definable entity, sleep terrors seem to be unknown to lay people, at least in Finland. Therefore, the use of single items or brief question series on sleep terrors may give inaccurate results in questionnaires. An interview of a person who has witnessed the nocturnal attack suspected to be sleep terror is essential because of the patient's impaired recall of the episode. Our results also support the general view that sleep terrors are rare in adults.

Nocturnal enuresis in a nationwide twin cohort.

We studied the occurrence of nocturnal enuresis (bedwetting) after the age of 4 years, using a questionnaire in a well-defined population, the Finnish Twin Cohort, which consists of 11,220 subjects aged 33-60 years, including 1298 monozygotic and 2419 dizygotic twin pairs. Structural equation modeling techniques were used to estimate variance components to compare different genetic models. Females reported enuresis in childhood "often" in 3.4% (males in 4.0%) and "sometimes" in 5.7% (8.0%). As adults, females had experienced enuresis "weekly" in 0.3% (males in 0.2%) and "monthly" in 0.07% (0.1%). Those who had experienced enuresis in childhood had had "at least sometimes" enuresis as adults in 5.4% of males and in 5.5% of females. Among those who reported they never had experienced enuresis as adults, 70.8% of males and in 77.9% of females had never experienced enuresis in childhood. For enuresis in childhood, the probandwise concordance rate was 0.43 for monozygotic and 0.19 for dizygotic pairs, and in adults 0.25 and 0, respectively. The proportion of total phenotypic variance attributed to genetic influences (due to dominance) was 67% in males (95% confidence interval 57-76%) and 70% in females (61-78%) in childhood enuresis. In conclusion, nocturnal enuresis is common in childhood and rare in adulthood. Our results confirm the central role of genetic liability in enuresis.

Insufficient sleep--a population-based study in adults.

STUDY OBJECTIVES: Insufficient sleep (sleep deprivation) is a common problem of considerable health, social, and economical impact. We assessed its prevalence and associations, and the role of genetic influences. DESIGN: Panel study based on questionnaires administered in 1981 and 1990. SETTING/PATIENTS: 12.423 subjects aged 33-60 years included in the Finnish Twin Cohort, representative of the Finnish population. INTERVENTIONS: N/A. MEASUREMENTS: A difference of 1 hour between the self-reports of the sleep need and the sleep length was considered insufficient sleep. Associations with education, life style, work, psychological characteristics and sleep-wake variables were assessed. Structural equation modelling techniques were used to compare genetic models among monozygotic and dizygotic twin pairs. RESULTS: In 1990, the prevalence of insufficient sleep was 20.4% (16.2% in men and 23.9% in women). 44% of those with insufficient sleep in 1981 also had it 9 years later (Spearman correlation for persistence 0.334). In multivariate analyses, the strongest positively associated factors were daytime sleepiness (women: odds ratio 3.87, 95% confidence limits 3.24-4.63/men: 3.77, 2.98-4.75), insomnia (2.48, 1.92-3.19/2.91, 2.17-3.90), not able to sleep without disturbance (1.95, 1.47-2.60/2.54, 1.66-3.89), and evening type (2.10, 1.65-2.69/1.73, 1.25-2.41). Among men, also weekly working hours > or =75 was strongly associated (3.23, 1.54-6.78). "Not working" was negatively associated in both genders (0.68, 0.51-0.89/0.59, 0.42-0.83). Two thirds of the interindividual variability in the liability to insufficient sleep was attributed to non-genetic factors. CONCLUSIONS: Insufficient sleep is a common and long-standing condition, most strongly associated with sleep/wake variables. One third of the liability to it is attributed to genetic influences. Sleep sufficiency should be assesssed in health examinations of working adults.

Twin studies in narcolepsy.

The genetic basis of narcolepsy is reflected by the strong association to human leukocyte antigen DR2 (most specifically to DQB1-0602) and the occasional familial occurrence, with several modes of transmission. At present, 12 monozygotic pairs with at least one affected twin have been reported. Of the three pairs considered concordant, the only well-documented pair is DR2 negative. Of the nine discordant pairs five are well documented, and all of these are DR2 positive. We performed a questionnaire study using a validated measure of narcoleptic symptoms (the Ullanlinna narcolepsy scale or UNS). The questionnaire was sent to 2,191 monozygotic twin pairs included in the Finnish Twin Cohort. In 225 pairs neither of the twins responded. In 1,550 pairs both twins responded, but in the answers of 228 pairs there were some missing data concerning the UNS items. Not a single case suggestive of narcolepsy was found. Narcolepsy in monozygotic twins is very rare. These facts support the hypothesis of a multifactorial etiology with a strong influence of nongenetic environmental factors.

Epidemiology of narcolepsy.

The prevalence of narcolepsy is usually presented at about 50/100,000. There are, however, marked differences of about 2,500-fold between the lowest and the highest reported prevalence. This discrepancy is at least partly explained by differences in the study populations and methods. There are, however, no earlier population-based epidemiological studies with polygraphically confirmed diagnoses. We studied the occurrence of symptoms resembling the two main manifestations of narcolepsy, i.e. abnormal sleep tendency and emotion-associated muscular weakness, in an adult twin cohort (n = 16,179) with a questionnaire. A total of 3.2% met the minimal diagnostic criteria of the International Classification of Sleep Disorders for narcolepsy. Eleven questionnaire items assessing the main manifestations of narcolepsy formed a measure called the Ullanlinna Narcolepsy Scale (UNS), which has been validated. The UNS score was calculated for 11,354 subjects. Those (n = 75) having a UNS score equal or higher than the lowest value in a narcolepsy patient group were studied. Thirty-one of them (fulfilling also the minimal diagnostic criteria) were interviewed, and those suspected of having narcolepsy (n = 5) were evaluated in the sleep laboratory. In three subjects the narcolepsy diagnosis was verified (all dizygotic, nonfamilial and human leukocyte antigen DR2/DQB-0602 positive), giving a prevalence of 0.026% in the adult Finnish (Caucasian) population.

Nightmares: familial aggregation and association with psychiatric disorders in a nationwide twin cohort.

We quantified the genetic influences affecting the liability to nightmares, and the association between nightmares and psychiatric disorders in a community-based sample. In 1990, 1,298 monozygotic (MZ) and 2,419 dizygotic (DZ) twin pairs aged 33-60 years responded to a questionnaire study in the Finnish Twin Cohort. Structural equation modeling was used to estimate genetic and environmental components of variance in the liability to nightmares. Records on hospitalization and long-term antipsychotic medication were used to estimate the period prevalence of serious psychiatric disorders. Nightmares were reported more frequently in females both in childhood and as adults. The correlation between occurrence in childhood and as adults was 0.69 in males and 0.71 in females. Polychoric correlations of occurrence within the twin pairs were 0. 45 in MZ and 0.21 in DZ pairs in childhood, and as adults 0.39 and 0. 18, respectively. The best fitting genetic model was that specifying additive genetic and unshared environmental effects. The estimated proportion of genetic effects in childhood was in males 44% (95% confidence interval [CI] 35-52%) and in females 45% (95% CI 38-52%) of the phenotypic variance. As adults the values were in males 36% (95% CI 27-44%) and in females 38% (95% CI 31-45%). Nightmare frequency and psychiatric disorders were linearly associated. Among those with the most frequent nightmares odds ratios (95% CI) were 3. 67 (2.48-5.42) for childhood and 5.87 (4.08-8.45) for adults compared with those never having nightmares. Nightmares are quite a stable trait from childhood to middle age. There are persistent genetic effects on the disposition to nightmares both in childhood and adulthood. Nightmares are significantly associated with psychiatric disorders.

Parasomnias: co-occurrence and genetics.

In clinical practice, parasomnias are often found to run in families and to co-occur. Several studies have indicated a role of genetic factors in them. In 1990, a questionnaire (response rate, 77%) sent to the Finnish Twin Cohort, a representative population sample aged 33-60 years, surveyed the frequency of five parasomnias (sleepwalking, sleeptalking, enuresis, bruxism, and nightmares) in childhood and as adults. In assessing the phenotypic covariation and shared genetic effects between the parasomnias, we used polychoric correlations and structural equation modelling. In childhood (n = 5856 individuals), co-occurrence is highest in sleeptalking with sleepwalking (R = 0.73), nightmares (R = 0.50), and bruxism (R = 0.43). As adults (n = 8567), the results are similar (R = 0.56, 0.43, and 0.39, respectively). The analyses of shared genetic effects included 815 monozygotic and 1442 dizygotic twin pairs with complete responses on four parasomnias as adults. The strongest genetic covariation was found in sleeptalking with sleepwalking, sleeptalking with bruxism, and in sleeptalking with nightmares. The estimated proportions of shared genetic effects were 50, 30, and 26%, respectively. The present results indicate that parasomnias share some common genetic background.

Effects of after-midnight intake of zolpidem and temazepam on driving ability in women with non-organic insomnia.

BACKGROUND: Occasionally, insomniac patients may take a sleeping pill after midnight. This may have consequences on their ability to drive a car and result in an increased risk of car accidents. METHODS: This double-blind, randomized, placebo-controlled, three-treatment three-period cross-over study investigated the effects of two frequently prescribed hypnotics of different classes in a real life condition on driving performance and psychomotor skills in insomniac women. Single doses of zolpidem 10 mg (Z), temazepam 20 mg (T) or placebo (P) were administered at 2:00 a.m. to 19 women aged 35-60 years in three treatment periods separated by wash-out periods of 3-14 days. After polysomnography at baseline and each treatment night, patients underwent, 5.5 h after drug intake at 7:30 a.m. on the next morning, a STISIM driving simulator test, and a subsequent neuropsychological test (FePsy). RESULTS: Eighteen insomniac women were included in the analysis (mean age 50 years, mean weight 69 kg, mean BMI 25.6 kg/m2). There were no differences between treatments for the primary outcome measure (mean time to collision; baseline: 0.120 s, P: 0.124, T: 0.118, Z: 0.124; P> or =0.12 for all pairwise comparisons). No differences were recorded for speed deviation and reaction time to tasks for the verum treatments, however, lane position deviation was greater after administration of zolpidem in comparison to both placebo and temazepam (P=0.025 and 0.05, respectively). There were no differences between treatments in the FePsy test. Both medications were well tolerated. CONCLUSIONS: 5.5 h after drug administration there were no major differences in psychomotor performances between both zolpidem and temazepam compared to placebo, which indicates the absence of significant residual effects at that time. However, certain patients were more susceptible than others to the drug effects (two patients with high number of collisions). This underlines the necessity to strongly advocate against the late intake of hypnotics if patients intend to drive a car early the next morning.

Autonomic nervous system function in narcolepsy.

A disturbance of the autonomic nervous system (ANS) in narcolepsy has been suggested, based on abnormalities on pupillometry, ejaculatory and cardiovascular function. The ANS function was studied by measuring the variation in the heart rate and blood pressure during provocations, using the following tests: deep breathing test, Valsalva test and Orthostatic test for heart rate reactivity measurements, and Orthostatic test for blood pressure control. Each test session gave seven variables, and these were compared to age-adjusted reference values in healthy normals. In 22 unmedicated narcoleptics (median age 50.5 y, range 18-70 y) the results did not differ from these. Seventeen of the patients were included in a controlled stimulant medication trial (selegiline 10-40 mg daily), and they showed no significant changes in the ANS variables except for a dose-dependent rise in heart ratio (placebo 1.32+/-1-0.13 and 40 mg 1.14+/-0.05; mean+/-SD) and a decrease in systolic blood pressure (placebo 5.8+/-9.7 and 40 mg 30.1+/-21.5 mmHg) on Orthostatic test. Although blood pressure decreases >/=30 mmHg (maximally 72 mmHg) occurred in 9 patients, they were asymptomatic. These changes are considered primarily to reflect the known characteristic of monoamine oxidase inhibitors to cause postural hypotonia. Abnormalities using these methods were not found, thus supporting the view that cardiovascular reflex abnormalities would be characteristic of narcolepsy.