Prevalence, incidence, evolution and associated factors of sleep paralysis in a longitudinal study of the US general population.

BACKGROUND AND OBJECTIVE: Sleep paralysis is a common phenomenon which causes and consequences are seldomly studied. The aim of this study was to investigate the incidence and prevalence of sleep paralysis (SP) in the American adult population and its evolution on a 3-year period. METHODS: This longitudinal study was conducted between 2002 and 2015 and included a representative sample of the US general population. A total of 12,218 subjects were initially interviewed (W1) and 10,931 were re-interviewed three years later (W2). The subjects participated in telephone interviews using the Sleep-EVAL expert system. Each interview lasted for about 1 h. SP episodes were assessed according to their frequency and duration. RESULTS: At W1, 9.7% (95%CI: 9.1%-10.3%) reported having ≥1 episode of SP in the previous year. At W2, 15.1% (95%CI: 14.4%-15.8%) reported SP. A total of 29.9% of subjects with SP at W1 still reported episodes at W2. The 1-year incidence was 2.7% (95%CI: 2.4-3.0%). After adjusting for age and sex, prevalent SP (i.e., present at W2) was predicted by age and race and the following factors present at W1: major depressive disorder, pain, hypersomnolence, cataplexy, hypnagogic and hypnopompic hallucinations, posttraumatic stress disorder, a reduction in sleep duration of ≥60 min, and the use of analgesic/antipyretic medication. Incident SP (i.e. new cases at W2) had similar predictive factors. DISCUSSION: Episodes of SP are frequent in the general population. Its persistence is predicted by several factors associated with narcolepsy like hypersomnolence and cataplexy but also by other factors like posttraumatic stress disorder or pain.

Medical comorbidity in narcolepsy: findings from the Burden of Narcolepsy Disease (BOND) study.

OBJECTIVE/BACKGROUND: The objective of this study was to evaluate medical comorbidity patterns in patients with a narcolepsy diagnosis in the United States. PATIENTS/METHODS: This was a retrospective medical claims data analysis. Truven Health Analytics MarketScan® Research Databases were accessed to identify individuals ≥18 years of age with ≥1 diagnosis code for narcolepsy (International Classification of Diseases (ICD)-9, 347.0, 347.00, 347.01, 347.1, 347.10, or 347.11) continuously insured between 2006 and 2010, and controls without narcolepsy matched 5:1 on age, gender, region, and payer. Narcolepsy and control subjects were compared for frequency of comorbid conditions, identified by the appearance of >1 diagnosis code(s) mapped to a Clinical Classification System (CCS) level 1 category any time during the study period, and on specific subcategories, including recognized narcolepsy comorbidities of obstructive sleep apnea (OSA) and depression. RESULTS: The final study group included 9312 subjects with narcolepsy and 46,559 controls (each group: average age, 46.1 years; 59% female). As compared with controls, patients with narcolepsy showed a statistically significant excess prevalence in all the CCS multilevel categories, the only exceptions being conditions originating in the perinatal period and pregnancy/childbirth complications. The greatest excess prevalence in the narcolepsy cohort was seen for mental illness (31.1% excess prevalence; odds ratio (OR) 3.8, 95% confidence interval (CI) 3.6, 4.0), followed by diseases of the digestive system (21.4% excess prevalence; OR 2.7, 95% CI 2.5, 2.8) and nervous system/sense organs (excluding narcolepsy; 20.7% excess prevalence; OR 3.7, 95% CI 3.4, 3.9). CONCLUSIONS: In this claims analysis, a narcolepsy diagnosis was associated with a wide range of comorbid medical illness claims, at significantly higher rates than matched controls.

Prevalence and comorbidity of nocturnal wandering in the U.S. adult general population.

OBJECTIVE: To assess the prevalence and comorbid conditions of nocturnal wandering with abnormal state of consciousness (NW) in the American general population. METHODS: Cross-sectional study conducted with a representative sample of 19,136 noninstitutionalized individuals of the U.S. general population ≥18 years old. The Sleep-EVAL expert system administered questions on life and sleeping habits; health; and sleep, mental, and organic disorders (DSM-IV-TR; International Classification of Sleep Disorders, version 2; International Classification of Diseases-10). RESULTS: Lifetime prevalence of NW was 29.2% (95% confidence interval [CI] 28.5%-29.9%). In the previous year, NW was reported by 3.6% (3.3%-3.9%) of the sample: 1% had 2 or more episodes per month and 2.6% had between 1 and 12 episodes in the previous year. Family history of NW was reported by 30.5% of NW participants. Individuals with obstructive sleep apnea syndrome (odds ratio [OR] 3.9), circadian rhythm sleep disorder (OR 3.4), insomnia disorder (OR 2.1), alcohol abuse/dependence (OR 3.5), major depressive disorder (MDD) (OR 3.5), obsessive-compulsive disorder (OCD) (OR 3.9), or using over-the-counter sleeping pills (OR 2.5) or selective serotonin reuptake inhibitor (SSRI) antidepressants (OR 3.0) were at higher risk of frequent NW episodes (≥2 times/month). CONCLUSIONS: With a rate of 29.2%, lifetime prevalence of NW is high. SSRIs were associated with an increased risk of NW. However, these medications appear to precipitate events in individuals with a prior history of NW. Furthermore, MDD and OCD were associated with significantly greater risk of NW, and this was not due to the use of psychotropic medication. These psychiatric associations imply an increased risk due to sleep disturbance.

Frequency of narcolepsy symptoms and other sleep disorders in narcoleptic patients and their first-degree relatives.

Narcolepsy is a rare neurological sleep disorder affecting around 0.05% of the general population. Genetic factors are known to have an important role in narcolepsy. However, because of its very low prevalence, it is difficult to have groups of comparison between first-degree relatives and general population subjects in order to identify a specific spectrum of disorders in these families. Consequently, from 157 Italian patients with narcolepsy, 263 first-degree relatives were recruited, two refused to participate. These family members were compared with a matched group of 1071 subjects selected from a sample of 3970 subjects representative of the general population of Italy (46 million inhabitants). Finally, 68 spouses of narcoleptic patients were used to assess for possible role of environmental factors. All subjects were interviewed by telephone using the Sleep-EVAL system. Nineteen cases of narcolepsy were discovered among the first-degree relatives of 17 probands (10.8%). Compared with the general population subjects, the relative risk of narcolepsy among female first-degree relatives was of 54.4 and of 105.1 among male first-degree relatives. First-degree relatives were also at higher risk for idiopatic hypersomnia (OR: 23.0), obstructive sleep apnea syndrome (OR: 6.8), adjustment sleep disorder (OR: 4.0), insufficient sleep syndrome (OR: 7.0), circadian rhythm disorders (OR: 2.5), REM behavior disorder (OR: 4.4), and sleep talking (OR: 2.0). The vulnerability to sleep disorders is very high in first-degree relatives and the link with different expressivity and severity of hypersomnia can be confirmed.

[Daytime consequences of insomnia complaints in the French general population]. / Répercussions diurnes de l'insomnie dans la population générale française.

Insomnia is a frequent symptom in the general population; numerous studies have proven this. In the past years, classifications have gradually given more emphasis to daytime repercussions of insomnia and to their consequences on social and cognitive functioning. They are now integrated in the definition of insomnia and are used to quantify its severity. If the daytime consequences of insomnia are well known at the clinical level, there are few epidemiological data on this matter. The aim of this study was to assess the daytime repercussions of insomnia complaints in the general population of France. A representative sample (n=5,622) aged 15 or older was surveyed by telephone with the help of the sleep-EVAL expert system, a computer program specially designed to evaluate sleep disorders and to manage epidemiological investigations. Interviews have been completed for 80.8% of the solicited subjects (n=5,622). The variables considered comprised insomnia and its daytime repercussions on cognitive functioning, affective tone, daytime sleepiness and diurnal fatigue. Insomnia was found in 18.6% of the sample. The prevalence was higher in women (22.4%) than in men (14.5%, p<0.001) with a relative risk of 1.7 (95% confidence interval 1.5 to 2) and was twice more frequent for subjects 65 years of age or older compared to subjects younger than 45 years. Approximately 30% of subjects reporting insomnia had difficulties initiating sleep. Nearly 75% of insomnia complainers reported having a disrupted sleep or waking up too early in the morning and about 40% said they had a non-restorative sleep. Repercussions on daytime functioning were reported by most insomnia subjects (67%). Repercussions on cognitive functioning changed according age, number of insomnia symptoms and the use of a psychotropic medication. A decreased efficiency was more likely to be reported by subjects between 15 and 44 years of age (OR: 2.9), those using a psychotropic (OR: 1.5), those reporting at least three insomnia symptoms (OR: 1.4) and women (OR: 1.4). The highest probability of the appearance of concentration difficulties was found in subjects younger than 65 Years, having a depressive disorder and using a psychotropic (15-44 years: OR 19.1; 45-64 years: OR 46.6). Difficulties maintaining attention were 15 times higher in subjects aged between 45 and 64 who were using a psychotropic and had also a depressive disorder. Memory difficulties were three times more likely to be reported by subjects using a psychotropic. At the affective level, irritability was 10 times more likely to be reported by subjects younger than 65 Years who were also using a psychotropic and had a depressive disorder. Independent of the presence of a mental disorder and the use of a psychotropic, subjects between 15 and 44 Years were five times more likely to be irritable following a bad sleep. Feeling depressed after a bad night's sleep was 18 times more likely to occur in subjects aged between 45 and 64 who were using a psychotropic and had a depressive disorder. Feeling anxious after a bad night's sleep was seven times more likely to occur in subjects with a depressive disorder. Daytime sleepiness was reported by approximately 20% of insomnia subjects. This rate was relatively comparable among gender, age groups, presence/absence of a mental disorder and use or not of a psychotropic. However, taking into account the interaction between age, use of a psychotropic and the presence of a mental disorder, subjects younger than 65 years, using a psychotropic and having a depressive disorder were at least 10 times more likely to report daytime sleepiness. Subjects who were suffering the most diurnal symptoms of insomnia were those younger than 65 years. Several factors can be evoked to explain this fact. These subjects were, for the most part, likelier to have a stricter sleep/wake schedule because of constraints imposed by work, studies, child care, etc. Subjects older than 65 Years were generally retired and therefore less prone to sleepiness and to cognitive difficulties. Insomnia consequences were limited due to their inactivity. Complementary studies should be undertaken to describe the daytime repercussions of insomnia for this specific age group of the general population and to measure these repercussions.

[Sleep and insomnia markers in the general population]. / Sommeil et principaux indicateurs d'insomnie dans la population générale française.

Several epidemiological surveys performed in Western Europe reported a prevalence of insomnia symptoms between 20% and 40% of the general population. Women and elderly individuals were the most affected. Many events can occur during sleep and affect its quality. Daytime sleepiness, a consequence of lack of sleep and/or insomnia, is responsible for many road, work and domestic accidents. Therefore, insomnia may have important consequences both for individuals and society. This study performed in the non institutionalized French population reports the sleep habits of that population and the factors associated with insomnia. This epidemiological study was conducted with 5,622 subjects representative of the French general population. They were aged between 15 and 96 Years. The participation rate was 80.8%. The results showed that men and women have different sleep habits. Generally speaking, women went to bed about 12 minutes earlier than men and woke up later than men (p<0.001). Women also took more time to fall asleep than men but only when they were aged between 35 and 65 Years. Furthermore, women had a longer sleep than men except between the ages of 55 and 74, where men slept significantly more than women. However, sleep efficiency was lower in women than in men who were over age 35. This was due to a greater frequency of nocturnal awakenings in women than in men. Sleep habits also changed with age: Bedtime became progressively earlier with advancing age and wake-up time was later when the subjects reached retirement age. Sleep latency progressively increased with age after 35. Similarly, disrupted sleep increased with age and was reported by more than half of subjects 75 years or older. We found also that evening or night workers showed irregularities in their sleep patterns: sleep latency was significantly longer - at least 12 minutes - compared to daytime and shift workers (p<0.001). They also had a shorter sleep duration of about 30 minutes compared to shift workers, and 40 minutes compared to daytime workers (p<0.001). Shift workers and evening or night workers had a lower sleep efficiency compared to daytime workers. Finally, in regions with greater density population (>100,000 inhabitants) sleep duration was shorter by approximately 10 minutes compared to localities with fewer than 5,000 residents (p<0.01). Similarly, bedtime and wake up hours were more related in regions with more than 100,000 inhabitants compared to small localities (fewer than 5,000 residents). Insomnia complaints, defined as the presence of at least one insomnia symptom accompanied by sleep dissatisfaction or use of a sleep medication, were reported by 18.6% of the sample. The prevalence was higher in women (22.4%) than in men (14.5%) and increased with age. However, the proportion of subjects dissatisfied with their sleep remained comparable for all age groups; it was the number of subjects using a sleep medication that increased with age. This was 3.2% in subjects 44 years or younger, 13.3% in subjects between 45 and 64 years, 22% of those between 65 and 74 years and almost a third of individuals 75 Years or older (32%; p<0.001). However, insomnia symptoms remained present for most of these consumers: 80.4% of those between 15 and 44 years, 87.9% of those between 45 and 64 Years, 81.4% of those between 65 and 74 years and 78.8% of subjects of 75 years or older. Compared to subjects in other epidemiological studies undertaken in England, Germany and Italy and using the same methodology, subjects in this study complained with their sleep more often. Insufficient sleep was found more often in the active population, which is subject to schedule constraints. Shift workers as well as evening or night workers were the most likely to have a sleep debt.

[A connection between insomnia and psychiatric disorders in the French general population]. / Liens entre insomnie et pathologie psychiatrique dans la population générale française.

Untreated insomnia often has repercussions on socio-professional or cognitive functioning of insomniacs. In industrialized countries, the prevalence of insomnia ranges between 10% and 48%, depending on the methodology and the measured time interval. However, few studies have examined the relationship between insomnia and mental disorder diagnoses. This epidemiological study on insomnia complaints was conducted on 5 622 subjects representative of the non-institutionalized French population aged 15 years or over. Sixteen interviewers using the Sleep-EVAL expert system performed telephone interviews. Insomnia complaints (defined as difficulty initiating or maintaining sleep, feeling unrefreshed at awakening accompanied by dissatisfaction with sleep quality or quantity, or use of sleep-promoting medication) were observed in 18.6% (95% confidence interval: 17.6% to 19.6%) of the sample. The median duration of insomnia complaints was five years. Regional variations in the prevalence of insomnia complaints were observed in France. In North 2 and Center 4 regions, the prevalence of insomnia complaints was higher compared to the rest of France with a relative risk of 1.4 (95% confidence interval: 1.1-1.6) time superior for the North region and 1.3 (95% CI: 1.0-1.6) for the Center 4 region. The lowest prevalence was registered in the Mediterranean area. In most regions, the prevalence of insomnia complaints was higher in women than in men with the exception of the South and West regions where the prevalence was similar. Subjects with insomnia complaints consulted more frequently compared to the rest of sample with an odds ratio of 3 to 1 [95% CI: 2.8 to 4.1]. Close to 20% of subjects were being treated for a physical disease at the time of the survey; subjects with insomnia complaints being twice more numerous (34.3%) than the rest of the sample (15.9%; p<0.001). To identify the main factors associated with insomnia complaints, socio-demographic and health variables were introduced in a multivariate model. Separated or divorced individuals (OR: 1.6); widowers (OR: 1.5); subjects aged between 45 and 65 years (OR: 1.4) or older than 65 (OR: 1.5); women (OR: 1.3); those with little or no education (OR: 1.4); and subjects living in the North region had higher reported insomnia complaints. Living in the East region (Mediterranean) was a protective factor (OR: 0.6). Furthermore, subjects with vascular diseases (OR: 2.0), musculo-skeletal diseases (OR: 2.0) or cardiac diseases (OR: 1.9) and those who had consulted a physician in the previous six months (OR: 2.7) had higher a probability of insomnia complaints. Subsequently, DSM IV insomnia diagnoses were examined in subjects who complained of insomnia. A diagnosis of primary insomnia was found in 7% of these subjects. A diagnosis of insomnia related to another mental disorder was found in 15.6% of insomnia complainers. A depressive disorder diagnosis was given in 10.8% of cases (mainly a major depressive disorder). This diagnosis was made more often among women and subjects of less than 65 years. An anxiety disorder diagnosis was given for 33.1% of insomnia complainers (an anxiety generalized disorder in about half the cases). About a quarter of insomnia complainers did not receive a diagnosis. This was the case more often for men and the subjects 65 years or older. If demographic and medical factors are relatively well documented at the epidemiological level, it is otherwise for psychiatric diagnosis associated with insomnia complaint. Very few studies in the general population have been done and still fewer of them have applied a positive and differential diagnosis process. In this study, we used the DSM IV classification to establish positive and differential diagnoses among subjects with insomnia complaints. Compared to other epidemiological studies, our study is distinguished by several aspects: 1) insomnia complaint had a narrower definition. It did not suffice that the subject reported insomnia symptoms, it was also necessary that the subject said s/he was dissatisfied with her/hr/his sleep or that s/he took measures to improve it (medication or sleep hygiene). This choice was motivated essentially by the fact that it is difficult, from a point of clinical point of view, to consider that an individual has insomnia solely based on the presence of symptoms, that, appreciated by a clinician, would resemble insomnia without that they make problem for the subject. 2) Several sleep habits were systematically collected. The majority of epidemiological studies are not centered on sleep problems, with the consequence that results do not allow a global view of factors that are associated with insomnia. 3) The various diagnostic categories of insomnia as well as elements of the differential diagnosis were applied. Thus, we can conclude that insomnia, as a diagnostic entity, including all its forms, is found in 5.6% of the French population. In the majority of cases, the insomnia complaint is part of the symptomatology of a mental disorder, mainly an anxiety disorder. This distinction is important since it helps the physician to determine therapeutic choices. To conclude, it is worthwhile to consider the number of insomnia complainers who had consulted a physician, mainly a general practitioner, in the six months prior to the study. This designates physicians as the first-line resource in the treatment and the prevention of sleep disorders.

[Methodology of a study on insomnia in the general population]. / Présentation et méthodologie d'une enquête sur l'insomnie en population générale.

The study of sleep disorders in the general population involves several methodological issues that need to be defined prior to proceeding to the epidemiological study. The rigor of the methodology is an important issue since it will determine the reliability of the data gathered. This paper describes the methodology used in an epidemiological study performed in the French general population using telephone interviews with the help of Sleep-EVAL, an expert system designed for this purpose. The study aimed to investigate the prevalence of insomnia disorders according to the DSM IV classification and the use of psychotropic medications in the general population. The methodological choices for this study were based on several considerations. First, the sample had to be representative of the French population. Second, the study had to be conducted in the shortest period of time. Third, the interviews had to be conducted with respect to a strict standardization and fourth, the realization costs had to be minimal for a maximum of data collected. The telephone interview procedure was chosen over postal and face-to-face interviews because it offered the possibility of conducting all the interviews from the same site. Supervision was easier. It also offered an absolute control in the application of the selection procedure. To draw the sample, a two-stage procedure was adopted. At the first stage, we pulled a random series of telephone numbers in each Nielsen region with respect to the size of the settlement. At the second stage, during the initial telephone contact, a household member was chosen using the Kish selection procedure. This method is based on the utilization of eight tables of selection that allows for the choice of the person to interview in a given household and keeps the representativeness of the sample. This technique is little used in telephone surveys because of its burden and its intrusive nature: the interviewer must collect the age and gender of all eligible subjects, to classify men from the oldest to youngest and then to classify women. However, it is the most rigorous selection method for epidemiological surveys. To reduce the refusal rates and to alleviate the work of interviewers, the Kish method was implanted in the computer software used for this study. For this study, the exclusion criteria were minimal. Only individuals younger than 15 years of age, those with a speech or hearing impairment and those who were too ill to perform the interview were not included. Subjects who refused to participate, those who hung up without speaking to the interviewer and those who hung up before completing at least half of the interview were tabulated as refusal. The participation rate was calculated by dividing the number of completed interviews by the number of eligible participants (completed interviews, refusals and telephone numbers where the interviewer was unable to determine if the individuals met an exclusion criterion). In this study, the participation rate was 80.8% (5 622 completed interviews/6 966 eligible households). The diagnostic tool used for this study was the Sleep-EVAL system, an expert system designed to conduct epidemiological studies in the general population. It is a level 2, non-monotonic system endowed with a causal reasoning able to provide sleep and mental disorders diagnoses according to the DSM IV classification for this study. Subsequent versions of Sleep-EVAL also included the International Classification of Sleep Disorders. System symbolic representation of the classifications was put in a compiled knowledge base. This knowledge base was read and interpreted by the inference engine at the beginning of the interview. During the interview, this interpretation changed as a function of the answers provided by the interviewee and by deductions made from the analysis of information the system already knew. All interviews began with a standard questionnaire about sociodemographic information and sleep habits. From these first answers, the Sleep-EVAL system emitted a series of diagnostic hypotheses that were confirmed or rejected with supplementary questions. The interview ended once all diagnostic possibilities were exhausted. The validity of the Sleep-EVAL system was demonstrated in different studies performed in sleep disorders clinics. There were several advantages in using such a tool to conduct epidemiological surveys. No special skills from the interviewers nor specific knowledge of sleep and mental disorders were required. All the questions were chosen and formulated by the Sleep-EVAL system. The interviewer had simply to read the questions as they appeared on the monitor screen and enter the interviewee's responses by clicking the appropriate answer or typing it on the keyboard. Missing answers were non-existent because there was no possibility of skipping a question or entering inconsistent answers. It also ensured the uniformity of the interviews. Furthermore, it allowed the exploration of infrequent diagnoses. In summary, the methodology used for this study allowed for the investigation of the sleep pathology of the French population in a short period of time: only three months were necessary to complete the 5 622 interviews. The use of a computerized tool greatly facilitated the training of the interviewers and also their work. Furthermore, it ensured a standardized administration of the interviews and the exploration of a broad range of disorders that could hardly be realized with traditional paper-pencil questionnaires.

Prevalence of narcolepsy symptomatology and diagnosis in the European general population.

OBJECTIVE: To determine the prevalence of narcolepsy in the general population of five European countries (target population 205,890,882 inhabitants). METHODS: Overall, 18,980 randomly selected subjects were interviewed (participation rate 80.4%). These subjects were representative of the general population of the UK, Germany, Italy, Portugal, and Spain. They were interviewed by telephone using the Sleep-EVAL expert system, which provided narcolepsy diagnosis according to the International Classification of Sleep Disorders (ICSD). RESULTS: Excessive daytime sleepiness was reported by 15% of the sample, with a higher prevalence in the UK and Germany. Napping two times or more in the same day was reported by 1.6% of the sample, with a significantly higher rate in Germany. Cataplexy (episodes of loss of muscle function related to a strong emotion), a cardinal symptom of narcolepsy, was found in 1.6% of the sample. An ICSD narcolepsy diagnosis was found in 0.047% of the sample: The narcolepsy was severe for 0.026% of the sample and moderate in 0.021%. CONCLUSION: This is the first epidemiologic study that estimates the prevalence of narcolepsy in the general population of these five European countries. The disorder affects 47 individuals/100,000 inhabitants.

What are the contributing factors for insomnia in the general population?

Lack of a systematic assessment of insomnia has led to large variations in its reported prevalence in the general population. This study aims to provide new guidelines to assess insomnia prevalence. A cross-sectional telephone survey using the Sleep-EVAL system was done with 24,600 general population-based subjects 15 years and older representative of general populations (France, the UK, Germany, Italy, Portugal, and Spain) consisting of 251,405,391 inhabitants. The overall participation rate was 81.0%. Within the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) symptomatology for insomnia, 27.2% (95% confidence interval: 26.6-27.8%) of the sample reported difficulty initiating sleep (DIS) (10.1%) or maintaining sleep (DMS) (disrupted sleep (DS): 18.0%; early morning awakening (EMA): 10.9%) or nonrestorative sleep (NRS) (8.9%) at least three times per week; 48.5% of them were concomitantly suffering of a DSM-IV sleep/mental disorder. A factor analysis identified several variables strongly related to each of the major factors of insomnia allowing: (1) The narrowing of the definition of insomnia: the prevalence of insomnia decreased to 16.8% with 64.5% of insomnia subjects having a DSM-IV sleep/mental disorder; (2) The identification of a sleep-deprived (voluntary or not) group without insomnia symptoms, representing 2.1% (1.9-2.3%) of the sample. Interestingly, the latter group closely matched the definition of insufficient sleep syndrome as described by the International Classification of Sleep Disorders (ICSD). Using more delineated criteria to assess insomnia increases the recognition of subjects complaining about sleep. Classifications should be amended to improve the correct identification of insomnia. Sleep-deprived subjects should also not be neglected.

Correlates of global sleep dissatisfaction in the German population.

STUDY OBJECTIVES: Global sleep dissatisfaction (GSD) is not part of the habitual insomnia symptoms in epidemiological studies. Furthermore, none of these studies has examined the relative importance of the various factors correlated to sleep dissatisfaction. This study aims to examine the links between GSD and insomnia and to find the factors contributing to GSD. DESIGN: A cross-sectional telephone survey was conducted in Germany (66 million inhabitants 15 years of age or older) with a representative sample of 4,115 subjects aged 15 years or older. Interviewers used the Sleep-EVAL system. The questionnaire covered several topics that were grouped into six classes of variables identified as potential factors associated with sleep dissatisfaction: sociodemographic descriptors, environmental factors, life habits, health status, psychological factors, sleep/wake factors. SETTING: N/A. PARTICIPANTS: A representative sample of 4,115 subjects aged 15 years or older INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Overall, 7% of the subjects reported being GSD; 95.5% of them had at least one insomnia symptom. The duration of insomnia symptom(s) was 20 months longer in GSD subjects compared to insomnia subjects without GSD. The prevalence of GSD was higher in women than in men and increased with age. The most significant predictive factors for GSD were: 1) for sleep/wake schedule variables: night sleep duration less than 6 hours (OR: 4.0 and over) and sleep latency greater than 30 minutes. 2) for sociodemographic variables: age between 65 and 74 (OR: 6.7) 3) for health variables: Upper airway disease (OR: 7.1); 4) for mental health variables: anxiety symptoms (OR: 3.0); 5) for environmental factors: too hot bedroom (OR=2.5) 6) for life habit factors: the need of a particular object in order to fall asleep (OR: 2.4). CONCLUSIONS: This study confirms that GSD is a better indicator of an underlying pathology than the classical insomnia symptoms alone: compared to insomniac subjects without GSD, subjects with GSD were two times more likely to report excessive daytime sleepiness, and eight times more likely to have a diagnosis of sleep or mental disorder. Furthermore, in car drivers, road accidents in the previous year were two times more frequent with GSD drivers as compared to insomnia drivers without GSD. Subjects with GSD were more than 10 times more likely to seek help for their sleep problems and five times more likely to use a sleep medication than insomnia subjects without GSD.

How age and daytime activities are related to insomnia in the general population: consequences for older people.

OBJECTIVES: To determine the role of activity status and social life satisfaction on the report of insomnia symptoms and sleeping habits. DESIGN: Cross-sectional telephone survey using the Sleep-EVAL knowledge base system. SETTING: Representative samples of three general populations (United Kingdom, Germany, and Italy). PARTICIPANTS: 13,057 subjects age 15 and older: 4,972 in the United Kingdom, 4,115 in Germany, and 3,970 in Italy. These subjects were representative of 160 million inhabitants. MEASUREMENTS: Clinical questionnaire on insomnia and investigation of associated pathologies (psychiatric and neurological disorders). RESULTS: Insomnia symptoms were reported by more than one-third of the population age 65 and older. Multivariate models showed that age was not a predictive factor of insomnia symptoms when controlling for activity status and social life satisfaction. The level of activity and social interactions had no influence on napping, but age was found to have a significant positive effect on napping. CONCLUSIONS: These results indicate that the aging process per se is not responsible for the increase of insomnia often reported in older people. Instead, inactivity, dissatisfaction with social life, and the presence of organic diseases and mental disorders were the best predictors of insomnia, age being insignificant. Healthy older people (i.e., without organic or mental pathologies) have a prevalence of insomnia symptoms similar to that observed in younger people. Moreover, being active and satisfied with social life are protective factors against insomnia at any age.

Risk factors for sleep bruxism in the general population.

OBJECTIVE: Sleep bruxism can have a significant effect on the patient's quality of life. It may also be associated with a number of disorders. However, little is known about the epidemiology of sleep bruxism and its risk factors in the general population. DESIGN: Cross-sectional telephone survey using the Sleep-EVAL knowledge based system. SETTINGS: Representative samples of three general populations (United Kingdom, Germany, and Italy) consisting of 158 million inhabitants. PARTICIPANTS: Thirteen thousand fifty-seven subjects aged > or = 15 years (United Kingdom, 4,972 subjects; Germany, 4,115 subjects; and Italy, 3,970 subjects). INTERVENTION: None. MEASUREMENTS: Clinical questionnaire on bruxism (using the International Classification of Sleep Disorders [ICSD] minimal set of criteria) with an investigation of associated pathologies (ie, sleep, breathing disorders, and psychiatric and neurologic pathologies). RESULTS: Grinding of teeth during sleep occurring at least weekly was reported by 8.2% of the subjects, and significant consequences from teeth grinding during sleep (ie, muscular discomfort on awakening, disturbing tooth grinding, or necessity of dental work) were found in half of these subjects. Moreover, 4.4% of the population fulfilled the criteria of ICSD sleep bruxism diagnosis. Finally, subjects with obstructive sleep apnea syndrome (odds ratio [OR], 1.8), loud snorers (OR, 1.4), subjects with moderate daytime sleepiness (OR, 1.3), heavy alcohol drinkers (OR, 1.8), caffeine drinkers (OR, 1.4), smokers (OR, 1.3), subjects with a highly stressful life (OR, 1.3), and those with anxiety (OR, 1.3) are at higher risk of reporting sleep bruxism. CONCLUSIONS: Sleep bruxism is common in the general population and represents the third most frequent parasomnia. It has numerous consequences, which are not limited to dental or muscular problems. Among the associated risk factors, patients with anxiety and sleep-disordered breathing have a higher number of risk factors for sleep bruxism, and this must raise concerns about the future of these individuals. An educational effort to raise the awareness of dentists and physicians about this pathology is necessary.

Comparability of sleep disorders diagnoses using DSM-IV and ICSD classifications with adolescents.

STUDY OBJECTIVES: The use of diagnostic classifications to define sleep disorders is still unusual in epidemiological studies assessing the prevalence of sleep disorders in an adolescent population. DESIGN: Cross-sectional study. Representative samples of general populations in United Kingdom, Germany and Italy were selected and interviewed by telephone about their sleep habits, sleep and mental disorder diagnoses. Overall, 724 adolescents ages 15-18 years and 1447 young adults ages 19 to 24 years were interviewed. ICSD-90 and DSM-IV diagnoses provided by the Sleep-EVAL expert system were used for the comparisons. SETTING: N/A. PARTICIPANTS: N/A. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: 8% of the adolescents and 12.6% of the young adults had ICSD dyssomnia or sleep disturbances associated with a mental disorder. According to the DSM-IV classification, 5.7% of the adolescents and 8.1% of the young adults had a dyssomnia diagnosis. The comparison between the two classifications show that 73.2% of adolescents and young adults with a DSM-IV dyssomnia diagnosis also had similar ICSD diagnosis. The reverse comparison, ICSD vs. DSM-IV, shows that 39.8% of the subjects with an ICSD diagnosis had a DSM-IV diagnosis. DSM-IV primary insomnia was the most frequent diagnosis. Subjects with such a diagnosis were found in about 10 different ICSD diagnoses, mainly inadequate sleep hygiene, psychophysiological or idiopathic insomnia and insufficient sleep syndrome. CONCLUSIONS: ICSD-90 classification provided higher prevalence of sleep disorder diagnoses than the DSM-IV classification. In adolescents and young adults, DSM-IV primary insomnia is two times more often associated with ICSD inadequate sleep hygiene than with ICSD psychophysiological or idiopathic insomnia.

Prevalence and patterns of problematic sleep among older adolescents.

OBJECTIVE: Despite many constraints on time schedules among teenagers, epidemiological data on sleep complaints in adolescence remain limited and are nonexistent for sleep disorders. This study provides additional data on sleep habits and DSM-IV sleep disorders in late adolescence. METHOD: A representative sample of 1,125 adolescents aged 15 to 18 years was interviewed by telephone using the Sleep-EVAL system. These adolescents came from 4 European countries: France, Great Britain, Germany, and Italy. Information was collected about sociodemographic characteristics, sleep/wake schedule, sleep habits, and sleep disorders and was compared with information from 2,169 young adults (19-24 years of age). RESULTS: Compared with young adults, adolescents presented with a distinct sleep/wake schedule: they went to sleep earlier, they woke up later, and they slept longer than young adults did. On weekends and days off, they also slept more than young adults did. However, the prevalence rates of sleep symptoms and sleep disorders were comparable in both groups. Approximately 25% reported insomnia symptoms and approximately 4% had a DSM-IV insomnia disorder. Fewer than 0.5% had a circadian rhythm disorder. CONCLUSIONS: Prevalence of insomnia disorders is lower in the adolescent population than in middle-aged or elderly adults. However, a rate of 4% in this young population is important given their young age and the consequences for daytime functioning.

Sleep disturbances and psychiatric disorders associated with posttraumatic stress disorder in the general population.

The aim of the study was to assess sleep disturbances in subjects with posttraumatic stress disorder (PTSD) from an urban general population and to identify associated psychiatric disorders in these subjects. The study was performed with a representative sample of 1,832 respondents aged 15 to 90 years living in the Metropolitan Toronto area who were surveyed by telephone (participation rate, 72.8%). Interviewers used Sleep-EVAL, an expert system specifically designed to conduct epidemiologic studies of sleep and mental disorders in the general population. Overall, 11.6% of the sample reported having experienced a traumatic event, with no difference in the proportion of men and women. Approximately 2% (1.8%) of the entire sample were diagnosed by the system as having PTSD at the time of interview. The rate was higher for women (2.6%) than for men (0.9%), which translated into an odds ratio (OR) of 2.8 (95% confidence interval [CI], 1.3 to 6.1). PTSD was strongly associated with other mental disorders: 75.7% of respondents with PTSD received at least one other diagnosis. Most concurrent disorders (80.7%) appeared after exposure to the traumatic event. Sleep disturbances also affected about 70% of the PTSD subjects. Violent or injurious behaviors during sleep, sleep paralysis, sleep talking, and hypnagogic and hypnopompic hallucinations were more frequently reported in respondents with PTSD. Considering the relatively high prevalence of PTSD and its important comorbidity with other sleep and psychiatric disorders, an assessment of the history of traumatic events should be part of a clinician's routine inquiry in order to limit chronicity and maladjustment following a traumatic exposure. Moreover, complaints of rapid eye movement (REM)-related sleep symptoms could be an indication of an underlying problem stemming from PTSD.

Is sleep-disordered breathing an independent risk factor for hypertension in the general population (13,057 subjects)?

UNLABELLED: OBJECTIVES Sleep-disordered breathing has been hypothesized to have a close relationship with hypertension but previous studies have reported mixed results. This is an important health issue that requires further clarification because of the potential impact on the prevention and control of hypertension. METHODS: The relationship between hypertension and three forms of sleep-disordered breathing (chronic snoring, breathing pauses and obstructive sleep apnea syndrome (OSAS)) was assessed using representative samples of the non-institutionalized population of the UK, Germany and Italy (159 million inhabitants). The samples were comprised of 13,057 individuals aged 15-100 years who were interviewed about their sleeping habits and their sleep symptoms over the telephone using the Sleep-EVAL system. RESULTS: OSAS was found in 1.9% (95% CI: 1.2% to 2.3%) of the UK sample, 1.8% (95% CI: 1.4% to 2.2%) of the German sample and 1.1% (95% CI: 0.8% to 1.4%) of the Italian sample. OSAS was an independent risk factor (odds ratio (OR): 9.7) for hypertension after controlling for possible confounding effects of age, gender, obesity, smoking, alcohol consumption, life stress, and, heart and renal disease. CONCLUSIONS: Results from three of the most populated countries in Western Europe indicate that OSAS is an independent risk factor for hypertension. Snoring and breathing pauses during sleep appeared to be non-significant predictive factors.

The place of confusional arousals in sleep and mental disorders: findings in a general population sample of 13,057 subjects.

Confusional arousals, or sleep drunkenness, occur upon awakening and remain unstudied in the general population. We selected a representative sample from the United Kingdom, Germany, and Italy (N = 13,057) and conducted telephone interviews. Confusional arousals were reported by 2.9% of the sample: 1% (95% confidence interval: .8 to 1.2%) of the sample also presented with memory deficits (53.9%), disorientation in time and/or space (71%), or slow mentation and speech (54.4%), and 1.9% (1.7% to 2.1%) reported confusional arousals without associated features. Younger subjects (< 35 years) and shift or night workers were at higher risk of reporting confusional arousals. These arousals were strongly associated with the presence of a mental disorder with odds ratios ranging from 2.4 to 13.5. Bipolar and anxiety disorders were the most frequently associated mental disorders. Furthermore, subjects with Obstructive Sleep Apnea Syndrome (OSAS), hypnagogic or hypnopompic hallucinations, violent or injurious behaviors, insomnia, and hypersomnia are more likely to suffer from confusional arousals. Confusional arousals appears to occur quite frequently in the general population, affecting mostly younger subjects regardless of their gender. Physicians should be aware of the frequent associations between confusional arousals, mental disorders, and OSAS. Furthermore, the high occurrence of confusional arousals in shift or night workers may increase the likelihood of inappropriate response by employees sleeping at work.

Differentiating DSM-IV anxiety and depressive disorders in the general population: comorbidity and treatment consequences.

OBJECTIVE: To attempt, for the first time, to apply a positive and differential diagnosis process in the general population during interviews using DSM-IV classification to ascertain the profile and occurrence of concomitant mental disorders. METHOD: A representative sample of 1832 individuals aged 15 years or older living in the metropolitan area of Toronto were interviewed by means of telephone interviews. The participation rate was 72.8%. RESULTS: Overall, 13.2% (n = 242) of the sample had either a mood disorder (n = 127; 6.9%) or an anxiety disorder (n = 170; 9.3%) at the time of their interview. The prevalence was higher among women (16.5%) than among men (9.7%), with an odds ratio of 1.8. The comorbidity of mood and anxiety disorders was found in 3% (n = 55) of the sample. Less than one-third of respondents with a mood and/or anxiety disorder were being treated by a physician for a mental disorder. However, these individuals were greater consumers of health care services. Most of them consulted a physician an average of 5 times in the past year. Individuals on medication diagnosed with a mood and an anxiety disorder consulted a physician an average of 12 times in the past year. Only 13% of them were treated with antidepressants and under 9% with anxiolytics. CONCLUSIONS: More than 70% of subjects with a mood disorder also complained of insomnia. With the differential process, 12% of the subjects manifesting a full-fledged anxiety disorder were diagnosed with only a mood disorder because the anxiety occurred only in the course of the mood disorder. About two-thirds of the subjects diagnosed in this study were undiagnosed and untreated by their physician.