Øystein Vedaa

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.

A randomized controlled trial with bright light and melatonin for delayed sleep phase disorder: Effects on subjective and objective sleep

Delayed sleep phase disorder (DSPD) is assumed to be common amongst adolescents, with potentially severe consequences in terms of school attendance and daytime functioning. The most common treatment approaches for DSPD are based on the administration of bright light and/or exogenous melatonin with or without adjunct behavioural instructions. Much is generally known about the chronobiological effects of light and melatonin. However, placebo-controlled treatment studies for DSPD are scarce, in particular in adolescents and young adults, and no standardized guidelines exist regarding treatment. The aim of the present study was, therefore, to investigate the short- and long-term effects on sleep of a DSPD treatment protocol involving administration of timed bright light and melatonin alongside gradual advancement of rise time in adolescents and young adults with DSPD in a randomized controlled trial and an open label follow-up study. A total of 40 adolescents and young adults (age range 16–25 years) diagnosed with DSPD were recruited to participate in the study. The participants were randomized to receive treatment for two weeks in one of four treatment conditions: dim light and placebo capsules, bright light and placebo capsules, dim light and melatonin capsules or bright light and melatonin capsules. In a follow-up study, participants were re-randomized to either receive treatment with the combination of bright light and melatonin or no treatment in an open label trial for approximately three months. Light and capsules were administered alongside gradual advancement of rise times. The main end points were sleep as assessed by sleep diaries and actigraphy recordings and circadian phase as assessed by salivary dim light melatonin onset (DLMO). During the two-week intervention, the timing of sleep and DLMO was advanced in all treatment conditions as seen by about 1 h advance of bed time, 2 h advance of rise time and 2 h advance of DLMO in all four groups. Sleep duration was reduced with approximately 1 h. At three-month follow-up, only the treatment group had maintained an advanced sleep phase. Sleep duration had returned to baseline levels in both groups. In conclusion, gradual advancement of rise time produced a phase advance during the two-week intervention, irrespective of treatment condition. Termination of treatment caused relapse into delayed sleep times, whereas long-term treatment with bright light and melatonin (three months) allowed maintenance of the advanced sleep phase.

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.

Systematic review of the relationship between quick returns in rotating shift work and health-related outcomes

A systematic literature search was carried out to investigate the relationship between quick returns (i.e. 11.0 hours or less between two consecutive shifts) and outcome measures of health, sleep, functional ability and work–life balance. A total of 22 studies published in 21 articles were included. Three types of quick returns were differentiated (from evening to morning/day, night to evening, morning/day to night shifts) where sleep duration and sleepiness appeared to be differently affected depending on which shifts the quick returns occurred between. There were some indications of detrimental effects of quick returns on proximate problems (e.g. sleep, sleepiness and fatigue), although the evidence of associations with more chronic outcome measures (physical and mental health and work–life balance) was inconclusive. Practitioner Summary: Modern societies are dependent on people working shifts. This study systematically reviews literature on the consequences of quick returns (11.0 hours or less between two shifts). Quick returns have detrimental effects on acute health problems. However, the evidence regarding effects on chronic health is inconclusive.

Prospective study of predictors and consequences of insomnia: personality, lifestyle, mental health, and work-related stressors

OBJECTIVE To prospectively investigate the reciprocal relationships between personality traits, lifestyle factors, mental health, sleepiness, and work-related stressors against insomnia. METHODS A total of 799 Norwegian shift-working nurses (mean age 33.2 years, 90% female) participated in this prospective cohort study. They were assessed on self-report instruments (Bergen Insomnia Scale, Diurnal Type Scale, Hospital Anxiety and Depression Scale, Negative Acts Questionnaire-Revised, Work-Family Interface Scale, among others) in 2008/2009 (wave 1) and 2011 (wave 3). Structural equation modeling was employed to investigate the bidirectional relationship between a wide range of individual and work-related variables and insomnia. RESULTS Languidity (β = 0.18***), anxiety (β = 0.11**), depression (β = 0.14***), exposure to bullying behavior (β = 0.08*), and negative spillover between work and family life (work to family, β = 0.08*; family to work, β = 0.07*) predicted increased symptoms of insomnia over time. Morningness (β = -0.09*) and positive spillover from work to family (β = -0.11**) predicted less symptoms of insomnia over time. No support was found for night work as a predictor of increased insomnia. Insomnia was a precursor for anxiety (β = 0.11**), but not for depression (*p <0.05, **p <0.01, ***p <0.001). CONCLUSION The data suggested that insomnia more often emerges as a consequence of individual and work-related factors than as a precursor to them. The scope of factors causing insomnia, and factors protecting against it, should be further investigated. Insomnia should be considered in prediction models for mental illnesses and as an outcome of adverse work-related experiences.

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. Trial registration: ClinicalTrials.gov identifier: NCT00834886.

Alcohol use among Norwegian students: Demographics, personality and psychological health correlates of drinking patterns

Aims: This study investigates demographic, personality, and psychological health correlates of different drinking patterns. Design: Students at the four largest institutions of higher education in Bergen municipality were invited via email to complete an internet-based questionnaire. The final sample size was 11,236 (39.4%), mean age 24.9 years (SD = 6.5), and 63.3% were women. The survey included the Alcohol Use Disorder Identification Test (AUDIT) and questions about demographics, personality traits, and symptoms of depression and anxiety. Binary logistic regressions were used to identify correlates of different drinking patterns. Results: A total of 53.0% of the students had an AUDIT score of or above 8 (i.e., hazardous drinking). Being native Norwegian, male, single, without children, non-religious, extroverted, unconscientious, and less open to experience were associated with higher AUDIT scores, drinking frequently, and binge drinking. Having parents with high alcohol or drug use increased the odds of engaging in binge drinking, but this factor was not associated with frequent drinking. Students scoring higher on neuroticism and openness were less likely to report problematic alcohol usage. Conclusions: A majority of the students reported alcohol habits that are associated with harm if they persist. This emphasises the need to examine the long-term consequences of students’ alcohol use.

Alcohol Use Among Business Students: Demographic, Personality, and Social Correlates of Increased Consumption

ABSTRACT This article aims to investigate drinking patterns among business students, and dispositional (e.g., demographics) and social factors (e.g., norms of alcohol use) that may explain differences in alcohol consumption between business and non-business students. Students in Bergen, Norway, were invited to participate in a survey. The sample consisted of 11,236 students. Binary logistic regressions were run to examine the relationship between institutional affiliation and alcohol use when controlling for covariates associated with alcohol use. Business students had higher alcohol consumption than other students, and shared several dispositional and social factors known to predict alcohol use. The heightened alcohol use among business students can partly be explained by dispositional factors, but seems mostly related to social norms and attitudes.

Recurrent cannabis use among Norwegian students: Prevalence, characteristics, and polysubstance use

Background: Research on cannabis has focused on lifetime use or regular/heavy use (i.e., daily or almost daily). Regular, albeit not necessarily daily, cannabis use has received less scientific attention. Objectives: This study aims to identify demographic and personality factors associated with recurrent cannabis use (i.e., cannabis usage 5 to 50 times in the last six months) and to investigate the relationship between cannabis use and use of other substances. Methods: Public and private university students (N = 11,236) in Bergen, Norway, participated in an online survey during autumn 2015. Binary logistic regression was run to identify individual characteristics related to recurrent cannabis use. Chi-square tests were conducted to investigate differences in substance use (alcohol, nicotine, and illicit drugs) between recurrent cannabis users and cannabis abstainers/low-frequency users. Results: A total of 4.0% of the students reported recurrent cannabis use. Students born in North America, non-Christians (compared to non-religious students), and men were more likely to be recurrent users. Recurrent cannabis users scored higher on extroversion and intellect/imagination compared to abstainers/low-frequency users. Male and female recurrent cannabis users had somewhat different characteristics (e.g., agreeableness scores were negatively associated with recurrent use among females but not among males). Recurrent cannabis use was overall strongly associated with polysubstance use. Conclusions: The prevalence of recurrent cannabis use among Norwegian students is low. Recurrent cannabis use seems more prevalent among individuals marked by extroversion and intellect/imagination, which supports the notion of cannabis use as a social activity for individuals identifying themselves as outgoing and unconventional. Cannabis use among students seems strongly associated with use of other substances, suggesting that cannabis should not be considered a replacement drug.

Sleep Detriments Associated with Quick Returns in Rotating Shift Work: A Diary Study

Objective: We aimed to compared sleep characteristics associated with quick returns (QRs, <11 hours between shift intervals) with those associated with other common shift transitions. Methods: Sixty-seven nurses completed a 2-week work and sleep diary (94.0% female, mean age 47.7 years). A multilevel fixed effects model was used to examine the sleep in QRs compared with two consecutive night shifts, two consecutive evening shifts, and two consecutive day shifts, respectively. Results: None of the other shift transitions studied encumbered as many detriments as QRs, which included short sleep duration (5.6 hours), slightly prolonged sleep onset latency, more abrupt ending of main sleep period, increased sleepiness, and higher level of perceived stress on the following shift. Conclusion: The study emphasizes the need for sufficient time for rest and recuperation between shifts.