The association between different sleep health dimensions and sex, age, education, circadian preference, and chronic insomnia: a representative population-based study.

Objectives: The aims were to explore multidimensional sleep health and the different dimensions of sleep health in the adult Norwegian population in relation to sex, age, education, circadian preference, and chronic insomnia. Methods: A representative sample of 1028 Norwegians, aged 18 + years completed a cross-sectional web-based survey. Sleep health was measured with the multidimensional RU_SATED scale, which assesses the dimensions of regularity, satisfaction, alertness, timing, efficiency, and duration. Insomnia was assessed with the Bergen Insomnia Scale. Data were analyzed with chi-square tests, t-tests, one-way ANOVAs, and regression analyses, as appropriate. Response rate was 33.5%. Results: Sleep health was better in males, with increasing age, and with higher educational level, and was poorer in participants with evening preference and chronic insomnia, compared to their respective counterparts. When investigating the different sleep health dimensions, males scored better than females on satisfaction (adjusted odds ratio [aOR] = 0.69, 95% CI = 0.51 to 0.93), timing (aOR = 0.66, 95% CI = 0.49 to 0.88), and efficiency (aOR = 0.68, 95% CI = 0.52 to 0.89). Older age was associated with better scores on regularity and satisfaction, whereas young age was associated with better scores on alertness and duration. High educational level was associated with better scores on alertness, timing, and duration. Evening types scored worse than morning types on regularity (aOR = 0.27, 95% CI = 0.18 to 0.41), satisfaction (aOR = 0.37, 95% CI = 0.26 to 0.53), and timing (aOR = 0.36, 95% CI = 0.26 to 0.51). Participants with chronic insomnia scored worse than participants without insomnia on all six sleep health dimensions. Conclusions: Sleep health differed significantly in relation to sex, age, education, circadian preference, and chronic insomnia. However, specific group differences were not equally evident in all sleep health dimensions.

Do people use methods or tricks to fall asleep? A comparison between people with and without chronic insomnia.

The present study estimated the frequency of using methods or tricks to fall asleep in the general Norwegian population. Further, people with chronic insomnia were compared with people without chronic insomnia. A representative sample of 1028 participants aged 18 years or older completed a web-based survey. The response rate was 33.5%. Insomnia symptoms were assessed with the validated Bergen Insomnia Scale, and chronic insomnia based on ICSD-3/DSM-5 criteria. Data were analysed with chi-square tests and logistic regression with adjustment for sex, age, education, and circadian preference. The results showed that 34.3% reported using a method or a trick to fall asleep, with relaxation exercises/breathing exercises being the most common. More females (39.5%) compared with males (29.1%) reported the use of a method/trick to fall asleep with an adjusted odds ratio (aOR) of 1.44. Chronic insomnia was reported by 24.9%, and clearly associated with higher use of such methods/tricks (53.7%; aOR = 3.49). Among the participants without chronic insomnia, 28.1% reported using methods/tricks to fall asleep. In conclusion, most people do not use methods or tricks to fall asleep, but chronic insomnia was associated with a higher frequency of such use. Still, since methods/tricks were also used by some participants without chronic insomnia, this may suggest that, for some people, this strategy may be effective or at least does not seem to disrupt the sleep onset process.

Clinical information predicting severe obstructive sleep apnea: A cross-sectional study of patients waiting for sleep diagnostics.

INTRODUCTION: Obstructive sleep apnea (OSA) is highly prevalent with serious health consequences. Demand for diagnostic studies is high, in many countries exceeding capacity. PURPOSE: The objective of this cross-sectional study was to identify predictors of severe OSA among patients on waiting lists for sleep studies, to better prioritize time to examinations. METHODS: The sample comprised 3646 patients (30.3% women) referred to a university clinic in Western Norway with suspected OSA. All patients underwent respiratory polygraphy. Severe OSA was defined by an apnea-hypopnea index ≥30. Information on symptoms (snoring, breathing cessations, daytime sleepiness) and medical history was collected with questionnaires, including prior diagnosis of angina, myocardial infarction, stroke, hypertension, depression or diabetes. Blood pressure was measured with thresholds of 90 and 140 mmHg defining diastolic and systolic hypertension. RESULTS: 15.7% had severe OSA. In multivariate logistic regression analysis, factors positively associated with severe OSA were increasing age, male sex, snoring, breathing cessations, BMI ≥30, diastolic hypertension, self-reported history of hypertension, and self-reported myocardial infarction. A prediction score (range 0-5) devised from 5 of these items (age ≥50, snoring, breathing cessations, BMI ≥30, and self-reported hypertension) had a sensitivity of 96.2% and a negative predictive value of 97.1% for severe OSA, when a score ≥2 was set as cut-off. CONCLUSIONS: Based on a prediction score derived from simple, easily available data, patients unlikely to suffer from severe OSA can be identified, and thus facilitate more urgent consideration of patients more likely to have severe OSA.

Daylight Saving Time preferences in Norway: Do individual chronotype and home address' latitude and longitude matter?

Daylight Saving Time is highly debated and associated with several health risks. Health experts recommend terminating adjusting the clock time, and to keep permanent standard (winter) time year around. The aims of the study were to investigate preferences for keeping or terminating this biannual adjustment of clock times and for permanent standard or summer time, in the general Norwegian population. Furthermore, we aimed to investigate whether such preferences depended on individual chronotype and home address' latitude/longitude. The online survey included 47,194 participants. Chronotype was measured with the Composite Scale of Morningness (morning types, intermediate types, evening types). Results showed that 78.2% preferred to terminate adjusting the clock time. Summer time year around was preferred by 61.5% whereas 29.1% preferred standard time year around, and 9.4% did not have any preference. Preferences for terminating adjustment of clock times and summer time year around were found in all chronotypes and regardless of living south (latitude 58-59°N), north (latitude 69-71°N), west (longitude 5-6°E) or east (longitude 19-31°E). However, a relatively larger proportion of evening chronotypes preferred to terminate adjusting the clock time compared to morning chronotypes, and relatively more people living north or east preferred termination than people living south or west, respectively. Permanent standard time was more strongly preferred by extreme morning types in comparison with the other chronotypes. In conclusion, nearly four out of five participants reported to prefer to terminate adjusting the clock time, in line with recommendations. However, in contrast to advice from health experts, permanent summer time was preferred by twice as many as permanent standard time. Both chronotype and home address' latitude and longitude mattered in regard to such preferences, but only to a small degree.

Self-reported seasonality is strongly associated with chronotype and weakly associated with latitude.

The aim of this study was to investigate the association between self-reported seasonality, i.e., seasonal variations in mood and related behavior, and chronotype, and between self-reported seasonality and home address' latitude. Data were collected from an online questionnaire with 45,338 participants. Seasonality and chronotype were measured with the Global Seasonality Score (GSS) and the Composite Scale of Morningness, respectively. The participants were categorized into extreme morning types, moderate morning types, intermediate types, moderate evening types, and extreme evening types. Furthermore, participants were categorized depending on home address' latitude. Data were analyzed with chi-square tests and logistic regression analyses adjusting for sex, age, marital status, level of education, and children living at home. Results showed that high seasonality (GSS 11+) was found in 20.9%. The prevalence dose-dependency ranged from 12.2% in extreme morning types to 42.6% in extreme evening types (adjusted OR = 4.21, CI = 3.27-5.41). The prevalence was higher in participants living in North-Norway (latitude from 65 to 71°N) versus South-Norway (latitude from 58 to 65°N) (23.8% versus 20.7%; adjusted OR = 1.18, CI = 1.08-1.28). When comparing the northernmost (69-71°N) to the southernmost (58-59°N) counties of Norway, the association was stronger (24.9% versus 18.7%; adjusted OR = 1.37, CI = 1.20-1.56). Among the adjusting variables, high seasonality was associated with female sex, younger age, being unmarried, low level of education, and not having children living at home. In conclusion, about one in five Norwegians reported high seasonality. High seasonality was strongly associated with late chronotype (being an evening type) and weakly associated with living in the north (high latitude).

No Effect of a Self-Help Book for Insomnia in Patients With Obstructive Sleep Apnea and Comorbid Chronic Insomnia - A Randomized Controlled Trial.

Objective: To compare the effects of a self-help book for insomnia to that of sleep hygiene advice in a randomized controlled trial with follow-up after about 3 months among patients who were diagnosed with obstructive sleep apnea (OSA) and comorbid chronic insomnia, and who were concurrently initiating treatment with continuous positive airway pressure (CPAP). Methods: In all, 164 patients were included. OSA was diagnosed and categorized based on a standard respiratory polygraphic sleep study using a type 3 portable monitor. The self-help book focused on cognitive behavioral therapy for insomnia. The main outcome measure was insomnia severity assessed with the Bergen Insomnia Scale (BIS) and the Insomnia Severity Index (ISI). Results: The scores on the BIS improved significantly from pre-treatment to follow-up in the sleep hygiene advice group (26.8 vs. 21.8) and in the self-help book group (26.3 vs. 22.4). Similarly, the ISI scores were significantly improved in both conditions (sleep hygiene: 17.0 vs. 14.1; self-help book: 16.6 vs. 13.6). No time × condition interaction effects were detected, suggesting that the self-help book did not improve insomnia symptoms more than the sleep hygiene advice. Conclusion: In this randomized controlled trial among patients with OSA and comorbid insomnia who were initiating CPAP treatment, concurrently treating their insomnia with a self-help book did not improve sleep more than sleep hygiene advice. The statistically significant improved sleep at follow-up in both groups is most likely explained by the CPAP treatment.

Prevalence of Parasomnias in Patients With Obstructive Sleep Apnea. A Registry-Based Cross-Sectional Study.

Objective: To assess the prevalence of parasomnias in relation to presence and severity of obstructive sleep apnea (OSA). We hypothesized higher parasomnia prevalence with higher OSA severity. Methods: The sample comprised 4,372 patients referred to a Norwegian university hospital with suspicion of OSA (mean age 49.1 years, 69.8% males). OSA was diagnosed and categorized by standard respiratory polygraphy (type 3 portable monitor). The patients completed a comprehensive questionnaire prior to the sleep study, including questions about different parasomnias during the last 3 months. Pearson chi-square tests explored differences according to the presence and severity of OSA. Furthermore, logistic regression analyses with the parasomnias as dependent variables and OSA severity as predictor were conducted (adjusted for sex, age, marital status, smoking, and alcohol consumption). Results: In all, 34.7% had apnea-hypopnea index (AHI) <5 (no OSA), 32.5% had AHI 5-14.9 (mild OSA), 17.4% had AHI 15-29.9 (moderate OSA), and 15.3% had AHI ≥30 (severe OSA). The overall prevalence of parasomnias was 3.3% (sleepwalking), 2.5% (sleep-related violence), 3.1% (sexual acts during sleep), 1.7% (sleep-related eating), and 43.8% (nightmares). The overall parasomnia prevalence was highest in the no OSA group. In the chi-square analyses, including all OSA groups, the prevalence of sleep-related violence and nightmares were inversely associated with OSA severity, whereas none of the other parasomnias were significantly associated with OSA severity. In adjusted logistic regression analyses the odds of sleepwalking was significantly higher in severe compared to mild OSA (OR = 2.0, 95% CI = 1.12-3.55). The other parasomnias, including sleep-related violence and nightmares, were not associated with OSA presence or severity when adjusting for sex and age. Conclusions: We found no increase in parasomnias in patients with OSA compared to those not having OSA. With the exception of sleepwalking, the parasomnias were not associated with OSA severity.

Age and sex differences in bedroom habits and bedroom preferences.

OBJECTIVE: The objective of this study was to estimate the prevalence of different bedroom habits/preferences, and to assess whether these habits/preferences differ with age and sex. METHODS: A population-based Norwegian cross-sectional telephone survey with 1001 of 1599 randomly selected adults (63% response rate) was performed. The questions about habits and preferences had different response alternatives (yes/no; up to eight response alternatives). Mean age was 47.5 years, and split into four groups (18-29, 30-44, 45-59, 60+ years). Age and sex differences were explored with chi-square statistics. RESULTS: Electronic media use in bed after bedtime was more common in younger compared to older age groups, with no sex difference. Daily use was reported by 61.8% of participants aged 18-29 years, compared to 3.7% among participants of 60+ years. Reading in bed after bedtime was more common with increasing age, and more common among females compared to males. Females and older participants more often rated their bed as very good. The older the participants, the colder the reported bedroom temperature. During winter, 48.5% of participants aged 60+ years reported a bedroom temperature of ≤12 °C. Many participants (39.2%) reported having their bedroom window always open at night, with no sex difference, but an increase with increasing age. Blackout curtains were used by 63.3%, with a drop in use with increasing age. Most participants preferred lying on the side when trying to sleep. Fewer older compared to younger participants preferred lying on the stomach. CONCLUSIONS: The findings may stimulate further studies exploring whether these habits/preferences may influence sleep and sleep disorders.

Prevalence of excessive sleepiness is higher whereas insomnia is lower with greater severity of obstructive sleep apnea.

PURPOSE: The objective of the present study was to investigate the prevalence of insomnia and excessive sleepiness in relation to the presence and severity of obstructive sleep apnea (OSA). METHODS: The sample consisted of patients referred to a university hospital on suspicion of OSA. In total, 1115 patients with mean age of 48 years were studied. Insomnia (Bergen Insomnia Scale) and excessive sleepiness (Epworth Sleepiness Scale) were diagnosed using validated questionnaires. The insomnia scale permits diagnosing insomnia using both old and new (from 2014) criteria. OSA was diagnosed and categorized based on a standard respiratory polygraphic sleep study using a type 3 portable monitor. RESULTS: OSA was diagnosed in 59.4 % of the referred patients. The prevalence of excessive sleepiness was higher with greater severity of OSA: 40.5 % in the patients without OSA (apnea-hypopnea index (AHI) <5), 46.5 % in mild OSA (AHI 5-14.9), 52.0 % in moderate OSA (AHI 15-29.9), and 58.0 % in severe OSA (AHI 30 or above). In contrast, the prevalence of insomnia using the 2014 diagnostic criteria showed an opposing prevalence: 54.2 % no OSA, 54.9 % mild OSA, 48.5 % moderate OSA, and 44.6 % severe OSA. Logistic and linear regression analyses showed that sleepiness was positively associated whereas insomnia was negatively associated with OSA severity and AHI. CONCLUSIONS: Both excessive sleepiness and insomnia were seen in high proportions of the patients referred on suspicion of OSA. Excessive sleepiness was higher whereas insomnia was lower with greater OSA severity.

The personality profile of young adults with delayed sleep phase disorder.

Delayed sleep phase disorder (DSPD) is a circadian rhythm sleep disorder characterized by a substantial delay in the major sleep period, resulting in difficulties falling asleep and awakening at a socially desirable time in the morning. This study is the first to investigate the NEO-Personality Inventory-Revised profile of young adults with DSPD. The study includes 40 patients diagnosed with DSPD (mean age = 20.7) and 21 healthy controls (mean age = 21.1). Results showed that young adults with DSPD scored higher on Neuroticism, lower on Extroversion, and much lower on Conscientiousness than the control group. Assessing the personality profile of young adults with DSPD before initiating treatment might provide useful clinical guidance regarding the individual needs for follow up during treatment.

A randomized controlled trial with bright light and melatonin for the treatment of delayed sleep phase disorder: effects on subjective and objective sleepiness and cognitive function.

Delayed sleep phase disorder (DSPD) is a circadian rhythm sleep disorder. Patients with DSPD have problems initiating sleep if they go to bed at a conventional time, and they often have problems waking at desired times. If they rise early in the morning, they usually experience severe sleepiness during morning hours. In the present study, we investigated the short- and long-term effects on measures of subjective and objective sleepiness and cognitive function of bright light and melatonin treatment alongside gradually advanced rise times in adolescents and young adults. Four treatment conditions were used in the short-term intervention (2 weeks): dim light (placebo) + placebo capsule, bright light + placebo capsule, dim light (placebo) + melatonin capsule, and bright light + melatonin capsule. This was followed by a long-term intervention (3 months) including 2 conditions: no treatment and combined bright light + melatonin treatment. Effects of treatment on sleepiness and fatigue were the primary outcome measures, and effects on cognitive function were secondary outcome measures. On a gradual advancement of the rise time schedule, all treatment conditions (bright light, melatonin, combination, and placebo) were almost equally effective in improving subjective daytime sleepiness, fatigue, and cognitive function in the 2-week study. The 2-week intervention showed no effect on objective sleepiness. Long-term treatment increased some of the positive effects seen after 2 weeks. The combined bright light and melatonin treatment improved subjective daytime sleepiness, fatigue, and cognitive function in the 3-month study. The no-treatment group returned to baseline values on most variables. In conclusion, a gradual advancement of rise times seems to produce positive effects on subjective sleepiness, fatigue, and cognitive performance during short-term treatment of patients with DSPD. However, the benefits from gradually advanced rise times seem to wear off, suggesting that the continuation of bright light and melatonin treatment is beneficial to maintain positive effects over time.

Objective measures of sleep and dim light melatonin onset in adolescents and young adults with delayed sleep phase disorder compared to healthy controls.

Delayed sleep phase disorder is characterized by a delay in the timing of the major sleep period relative to conventional norms. The sleep period itself has traditionally been described as normal. Nevertheless, it is possible that sleep regulatory mechanism disturbances associated with the disorder may affect sleep duration and/or architecture. Polysomnographic data that may shed light on the issue are scarce. Hence, the aim of this study was to examine polysomnographic measures of sleep in adolescents and young adults with delayed sleep phase disorder, and to compare findings to that of healthy controls. A second aim was to estimate dim light melatonin onset as a marker of circadian rhythm and to investigate the phase angle relationship (time interval) between dim light melatonin onset and the sleep period. Data from 54 adolescents and young adults were analysed, 35 diagnosed with delayed sleep phase disorder and 19 healthy controls. Results show delayed timing of sleep in participants with delayed sleep phase disorder, but once sleep was initiated no group differences in sleep parameters were observed. Dim light melatonin onset was delayed in participants with delayed sleep phase disorder, but no difference in phase angle was observed between the groups. In conclusion, both sleep and dim light melatonin onset were delayed in participants with delayed sleep phase disorder. The sleep period appeared to occur at the same circadian phase in both groups, and once sleep was initiated no differences in sleep parameters were observed.

Prevalence and correlates of delayed sleep phase in high school students.

PURPOSE: To investigate prevalence and correlates of delayed sleep phase, characterized by problems falling asleep in the evening and rising at adequate times in the morning, in a large sample of Norwegian high school students. METHODS: A randomized sample of 1285 high school students (aged 16-19 years) participated in an internet based study answering questions about sleep habits, height, weight, smoking, alcohol use, school grades, and anxiety and depression symptoms. Delayed sleep phase was operationalized as difficulties falling asleep before 2 a.m. at least three nights per week together with much or very much difficulty waking up in the morning. RESULTS: The results show a prevalence of delayed sleep phase of 8.4%. In all, 68% of these students (5.7% of the total sample) also reported problems advancing their sleep period as well as one daytime consequence (oversleeping at least two days a week or experiencing much/very much sleepiness at school). Delayed sleep phase was associated with lower average school grades, smoking, alcohol usage, and elevated anxiety and depression scores. CONCLUSIONS: Delayed sleep phase appears to be common amongst Norwegian adolescents and is associated with negative outcomes such as lower average school grades, smoking, alcohol usage, and elevated anxiety and depression scores.