Mélanie LeBlanc

The natural history of insomnia: a population-based 3-year longitudinal study.

BACKGROUND Despite its high prevalence, little information is available about the natural history of insomnia. The extent to which episodes of insomnia will persist or remit over time is difficult to predict. We examined the natural history of insomnia and describe the most common trajectories over 3 years. METHODS Three hundred eighty-eight adults (mean [SD] age, 44.8 [13.9] years; 61% women) were selected from a larger population-based sample on the basis of the presence of insomnia at baseline. They completed standardized sleep/insomnia questionnaires at 3 annual follow-up assessments. For each follow-up assessment, participants were classified into 1 of 3 groups (individuals with an insomnia syndrome, individuals with insomnia symptoms, and individuals with good sleep) on the basis of algorithms using standard diagnostic criteria for insomnia. Rates of persistent insomnia, remission, and relapse were computed for each group. RESULTS Of the study sample, 74% reported insomnia for at least 1 year (2 consecutive assessments) and 46% reported insomnia persisting over the entire 3-year study. The course of insomnia was more likely to be persistent in those with more severe insomnia at baseline (ie, insomnia syndrome) and in women and older adults. Remission rate was 54%; however, 27% of those with remission of insomnia eventually experienced relapse. Individuals with subsyndromal insomnia at baseline were 3 times more likely to remit than worsen to syndrome status, although persistence was the most frequent course in that group as well. CONCLUSION These findings indicate that insomnia is often a persistent condition, in particular when it reaches the diagnostic threshold for an insomnia disorder.

Insomnia and its relationship to health-care utilization, work absenteeism, productivity and accidents.

BACKGROUND AND PURPOSE To document and provide a micro analysis of the relationship between insomnia and health problems, health-care use, absenteeism, productivity and accidents. PARTICIPANTS AND METHODS A population-based sample of 953 French-speaking adults from Québec, Canada. Participants were categorized as having insomnia syndrome (SYND) or insomnia symptoms (SYMPT) or as good sleepers (GS). They completed questionnaires on sleep, health, use of health-care services and products, accidents, work absences and reduced work productivity. Data were also obtained from the Québec-government-administered health insurance board on selected variables (e.g., consultations with health-care professionals, diagnoses). RESULTS There were significantly more individuals in the SYND group relative to the GS group reporting at least one chronic health problem (83% vs. 53%; OR: 2.78) and who had consulted a health-care professional in the past year (81% vs. 60%; OR: 2.8). There were also higher proportions of individuals in the SYND group than in the GS group who had used prescription medications (57% vs. 30.7%; OR: 2.8), most notably to treat insomnia, mood and anxiety disorders, or who had used over-the-counter products (75.6% vs. 62.0%; OR: 1.8) and alcohol as a sleep aid (17.8% vs. 3.9%; OR: 4.6). In terms of daytime function, 25.0% of the SYND had been absent from work relative to 17.1% of GS (OR: 1.7), 40.6% reported having experienced reduced productivity compared to 12.3% of GS (OR: 4.8) and non-motor-vehicle accidents occurred at higher rates in the SYND group (12.5% vs. 6.4% for GS; OR: 2.4). No differences were found for hospitalisations or motor-vehicle accidents. Most of the associations remained significant even after controlling for psychiatric comorbidity. Rates for the SYMPT group were situated between SYND and GS on all major dependent variables. Furthermore, insomnia and fatigue were perceived as contributing significantly to accidents, absences and decreased work productivity, regardless of insomnia status. CONCLUSIONS This study indicates that insomnia is associated with significant morbidity in terms of health problems and health-care utilization, work absenteeism and reduced productivity, and risk of non-motor-vehicle accidents. Future studies should evaluate whether treating insomnia can reverse this morbidity.

Cognitive performance and sleep quality in the elderly suffering from chronic insomnia Relationship between objective and subjective measures

OBJECTIVE The objective of the present study was to evaluate the relationship between objective and subjective sleep quality and objective and subjective evaluation of cognitive performance in older adults suffering of chronic insomnia (using or not benzodiazepines, BZs) or self-reported good sleepers. METHODS Three groups of participants 55 years and older were evaluated: 20 insomnia sufferers using BZs chronically, 20 drug-free insomnia sufferers and 20 good sleepers. Objective sleep (PSG) and subjective sleep (sleep diaries, SD) were measured. Objective measures of cognitive performance (attention/concentration, verbal/visual memory, executive function and psychomotor speed) and subjective perception of daily performance were evaluated. RESULTS Correlational analysis revealed that objective and subjective measures of daytime performance are differentially related to sleep quality for the three groups. An objective good night of sleep is associated with better cognitive performance in good sleepers and drug-free individuals. On the other hand, the impression of having slept well is related to better cognitive performance in good sleepers and chronic insomnia sufferers using BZs. CONCLUSION Daytime performance and sleep quality are related, but differently so for a good sleeper, an insomnia sufferer without treatment, or one using BZs to alleviate sleep difficulties.

Prevalence of Insomnia and its Treatment in Canada

Objectives: To estimate the prevalence of insomnia and examine its correlates (for example, demographics and physical and mental health) and treatments. Methods: A sample of 2000 Canadians aged 18 years and older responded to a telephone survey about sleep, health, and the use of sleep-promoting products. Respondents with insomnia were identified using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, and the International Classification of Diseases, Tenth Edition, criteria. Results: Among the sample, 40.2% presented at least 1 symptom of insomnia (that is, trouble falling or staying asleep, or early morning awakening) for a minimum of 3 nights per week in the previous month, 19.8% were dissatisfied with their sleep, and 13.4% met all criteria for insomnia (that is, presence of 1 insomnia symptom 3 nights or more per week for at least 1 month, accompanied by distress or daytime impairment). Insomnia was associated with female sex, older age, and poorer self-rated physical and mental health. Thirteen per cent of respondents had consulted a health care provider for sleep difficulties once in their lifetime. Moreover, 10% had used prescribed medications for sleep in the previous year, 9.0% used natural products, 5.7% used over-the-counter products, and 4.6% used alcohol. There were differences between French- and English-speaking adults, with the former group presenting lower rates of insomnia (9.5%, compared with 14.3%) and consultation (8.7%, compared with 14.4%), but higher rates of prescribed medications (12.9%, compared with 9.3%) and the use of natural products (15.6%, compared with 7.4%). Conclusions: Insomnia is a prevalent condition, although few people seek professional consultation for this condition. Despite regional differences in the prevalence and treatments used to manage insomnia, prescribed medications remain the most widely used therapeutic option.

Insomnia in shift work

BACKGROUND Shift work disorder involves insomnia and/or excessive sleepiness associated with the work schedule. The present study examined the impact of insomnia on the perceived physical and psychological health of adults working on night and rotating shift schedules compared to day workers. METHODS A total of 418 adults (51% women, mean age 41.4 years), including 51 night workers, 158 rotating shift workers, and 209 day workers were selected from an epidemiological study. An algorithm was used to classify each participant of the two groups (working night or rotating shifts) according to the presence or absence of insomnia symptoms. Each of these individuals was paired with a day worker according to gender, age, and income. Participants completed several questionnaires measuring sleep, health, and psychological variables. RESULTS Night and rotating shift workers with insomnia presented a sleep profile similar to that of day workers with insomnia. Sleep time was more strongly related to insomnia than to shift work per se. Participants with insomnia in the three groups complained of anxiety, depression, and fatigue, and reported consuming equal amounts of sleep-aid medication. Insomnia also contributed to chronic pain and otorhinolaryngology problems, especially among rotating shift workers. Work productivity and absenteeism were more strongly related to insomnia. CONCLUSION The present study highlights insomnia as an important component of the sleep difficulties experienced by shift workers. Insomnia may exacerbate certain physical and mental health problems of shift workers, and impair their quality of life.

Monthly fluctuations of insomnia symptoms in a population-based sample

STUDY OBJECTIVES To document the monthly changes in sleep/insomnia status over a 12-month period; to determine the optimal time intervals to reliably capture new incident cases and recurrent episodes of insomnia and the likelihood of its persistence over time. DESIGN Participants were 100 adults (mean age = 49.9 years; 66% women) randomly selected from a larger population-based sample enrolled in a longitudinal study of the natural history of insomnia. They completed 12 monthly telephone interviews assessing insomnia, use of sleep aids, stressful life events, and physical and mental health problems in the previous month. A total of 1,125 interviews of a potential 1,200 were completed. Based on data collected at each assessment, participants were classified into one of three subgroups: good sleepers, insomnia symptoms, and insomnia syndrome. RESULTS At baseline, 42 participants were classified as good sleepers, 34 met criteria for insomnia symptoms, and 24 for an insomnia syndrome. There were significant fluctuations of insomnia over time, with 66% of the participants changing sleep status at least once over the 12 monthly assessments (51.5% for good sleepers, 59.5% for insomnia syndrome, and 93.4% for insomnia symptoms). Changes of status were more frequent among individuals with insomnia symptoms at baseline (mean = 3.46, SD = 2.36) than among those initially classified as good sleepers (mean = 2.12, SD = 2.70). Among the subgroup with insomnia symptoms at baseline, 88.3% reported improved sleep (i.e., became good sleepers) at least once over the 12 monthly assessments compared to 27.7% whose sleep worsened (i.e., met criteria for an insomnia syndrome) during the same period. Among individuals classified as good sleepers at baseline, risks of developing insomnia symptoms and syndrome over the subsequent months were, respectively, 48.6% and 14.5%. Monthly assessment over an interval of 6 months was found most reliable to estimate incidence rates, while an interval of 3 months proved the most reliable for defining chronic insomnia. CONCLUSIONS Monthly assessment of insomnia and sleep patterns revealed significant variability over the course of a 12-month period. These findings highlight the importance for future epidemiological studies of conducting repeated assessment at shorter than the typical yearly interval in order to reliably capture the natural course of insomnia over time.

Sequential Treatment for Chronic Insomnia: A Pilot Study

This article explores the efficacy of sequential treatment involving medication and cognitive behavioral treatment (CBT) for insomnia. In a multiple baseline across-subjects design, 6 participants with primary chronic insomnia received 1 of the following treatment sequences: (a) concurrent combination of medication and CBT for the 10-week treatment duration (Combined); (b) medication for the first 5 weeks, with introduction of CBT at week 4 and medication withdrawal after the 5th week resulting in treatment overlap during weeks 4 and 5 (Overlapping: Medication → Combined → CBT); and (c) medication alone for the first 5 weeks followed by CBT alone for an additional 5 weeks (Medication → CBT). Each sequence led to significant sleep improvements, but these improvements occurred at different times during the intervention. Participants in the Combined and in the Overlapping sequences improved their sleep during the 1st phase of treatment, whereas those in the Medication → CBT sequence improved mostly during the 2nd phase of treatment. These preliminary results suggest that a sequential treatment is effective for chronic insomnia. In addition, the results suggest that sleep improvements are more likely to emerge when CBT is introduced, with an Overlapping sequence showing a slight advantage over the other sequences. Additional clinical trials should be conducted with larger samples to replicate these preliminary findings.

USING THE IMPACT OF EVENT SCALE TO EVALUATE DISTRESS IN THE CONTEXT OF GENETIC TESTING FOR BREAST CANCER SUSCEPTIBILITY

The data obtained with two forms of the Impact of Event Scale were compared, one referring to a BRCA1/2 test result (IES-T) and another to cancer (IES-C). The sample consisted of 272 women with a family history suggestive of a BRCA1/2 mutation who underwent genetic testing and received results: noncarrier, carrier, or inconclusive. Globally, mean scores on the IES-C form were higher than those obtained on the IES-T form. Among carriers of a BRCA1/2 mutation, mean scores on the two forms were similar and agreement was good, as measured by the in-traclass correlation coefficient (.83; 95% 95% CI = .72, .91). Agreement between the forms was poor to fair among noncarriers (ICC = .38; CI = .15, .57) and women with an inconclusive result (ICC = .40; 95% CI = .26, 52). Having had cancer increased total scores but had little influence on agreement between scores on forms. These findings highlight the importance of carefully selecting the form of the Impact of Event Scale in the context of genetic testing for breast cancer susceptibility.

Familial Aggregation of Insomnia

Study Objectives: There is little information about familial aggregation of insomnia; however, this type of information is important to (1) improve our understanding of insomnia risk factors and (2) to design more effective treatment and prevention programs. This study aimed to investigate evidence of familial aggregation of insomnia among first‐degree relatives of probands with and without insomnia. Methods: Cases (n = 134) and controls (n = 145) enrolled in a larger epidemiological study were solicited to invite their first‐degree relatives and spouses to complete a standardized sleep/insomnia survey. In total, 371 first‐degree relatives (Mage = 51.9 years, SD = 18.0; 34.3% male) and 138 spouses (Mage = 55.5 years, SD = 12.2; 68.1% male) completed the survey assessing the nature, severity, and frequency of sleep disturbances. The dependent variable was insomnia in first‐degree relatives and spouses. Familial aggregation was claimed if the risk of insomnia was significantly higher in the exposed (relatives of cases) compared to the unexposed cohort (relatives of controls). The risk of insomnia was also compared between spouses in the exposed (spouses of cases) and unexposed cohort (spouses of controls). Results: The risk of insomnia in exposed and unexposed biological relatives was 18.6% and 10.4%, respectively, yielding a relative risk (RR) of 1.80 (p = .04) after controlling for age and sex. The risk of insomnia in exposed and unexposed spouses was 9.1% and 4.2%, respectively; however, corresponding RR of 2.13 (p = .28) did not differ significantly. Conclusions: Results demonstrate evidence of strong familial aggregation of insomnia. Additional research is warranted to further clarify and disentangle the relative contribution of genetic and environmental factors in insomnia.