Corrigendum to ‘Sleep and sleepiness in shift-working tram drivers’[Applied Ergonomics Sleep and sleepiness in shift-working tram drivers 88 (2020) 1…

2021

Recurrent On-Duty Sleepiness and Alertness Management Strategies in Long-Haul Airline Pilots

2018

Introduction We examined whether long-haul airline pilots without recurrent on-duty sleepiness obtain more prior sleep and use more effective in-flight alertness management strategies than their colleagues with recurrent on-duty sleepiness. Methods There were 51 pilots who flew at least twice from Helsinki to Asia. Of them, 44 flew at least twice back to Helsinki following 1 local night. On-duty sleepiness was measured by the Karolinska Sleepiness Scale (KSS), alertness management strategies by a diary, and sleep by a diary and activity monitor. Pilots who rated KSS ≥ 7 on each, some, or none of the flights were classified as "regularly", "sometimes", and "never" sleepy, respectively. This …

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

2018

Education is a frequently recommended remedy for driver sleepiness in occupational settings, although not many studies have examined its usefulness. To date, there are no previous on-road randomized controlled trials investigating the benefits of training on sleepiness among employees working in road transport. To examine the effects of an educational intervention on long-haul truck drivers' sleepiness at the wheel, amount of sleep between work shifts, and use of efficient sleepiness countermeasures (SCM) in association with night and non-night shift, a total of 53 truck drivers operating from southern Finland were allocated into an intervention and a control group using a stratified random…

Self-reported reasons for on-duty sleepiness among commercial airline pilots

2021

Experimental and epidemiological research has shown that human sleepiness is determined especially by the circadian and homeostatic processes. The present field study examined which work-related factors airline pilots perceive as causing on-duty sleepiness during short-haul and long-haul flights. In addition, the association between the perceived reasons for sleepiness and actual sleepiness levels was examined, as well as the association between reporting inadequate sleep causing sleepiness and actual sleep-wake history. The study sample consisted of 29 long-haul (LH) pilots, 28 short-haul (SH) pilots, and 29 mixed fleet pilots (flying both SH and LH flights), each of whom participated in a…

Cognitive behavioural therapy interventions for insomnia among shift workers: RCT in an occupational health setting

2019

Abstract Introduction The aim of the study was to compare the effectiveness of cognitive behavioural therapy interventions for insomnia (CBT-I) to that of a sleep hygiene intervention in a randomized controlled design among shift workers. We also studied whether the features of shift work disorder (SWD) affected the results. Methods A total of 83 shift workers with insomnia disorder were partially randomized into a group-based CBT-I, self-help CBT-I, or sleep hygiene control intervention. The outcomes were assessed before and after the interventions and at 6-month follow-up using questionnaires, a sleep diary, and actigraphy. Results Perceived severity of insomnia, sleep-related dysfunction…

TRIB1 constitutes a molecular link between regulation of sleep and lipid metabolism in humans.

2012

Epidemiological studies show association between sleep duration and lipid metabolism. In addition, inactivation of circadian genes induces insulin resistance and hyperlipidemia. We hypothesized that sleep length and lipid metabolism are partially controlled by the same genes. We studied the association of total sleep time (TST) with 60 genetic variants that had previously been associated with lipids. The analyses were performed in a Finnish population-based sample (N = 6334) and replicated in 2189 twins. Finally, RNA expression from mononuclear leucocytes was measured in 10 healthy volunteers before and after sleep restriction. The genetic analysis identified two variants near TRIB1 gene th…

Sleep restriction for the duration of a work week impairs multitasking performance

2010

It is important to develop shift schedules that minimise the chance for sleep-related human error in safety-critical domains. Experimental data on the effects of sleep restriction (SR) play a key role in this development work. In order to provide such data, we conducted an experiment in which cognitively demanding and long-duration task performance, simulating task performance at work, was measured under SR and following recovery. Twenty healthy male volunteers, aged 19-29 years, participated in the study. Thirteen of them had first two baseline days (8-h sleep opportunity per day), then five SR days (4-h sleep) and finally two recovery days (8-h sleep). Seven controls were allowed to sleep…

Sleep and sleepiness in shift-working tram drivers

2020

Driver sleepiness contributes to traffic accidents. However, sleepiness in urban public transport remains an understudied subject. To fill this gap, we examined the sleepiness, sleep, and on-duty sleepiness countermeasures (SCMs) in 23 tram drivers working morning, day, and evening shifts for three weeks. Sleepiness was measured using Karolinska Sleepiness Scale (KSS). Nocturnal total sleep time (TST) was measured with wrist actigraphy. SCMs and naps were self-reported with a smartphone application. Caffeine and napping were considered effective SCMs. Severe sleepiness (KSS >= 7) was observed in 22% of shifts with no differences between shift types. Rest breaks were associated with slight r…

Lifestyle counseling to reduce body weight and cardiometabolic risk factors among truck and bus drivers – a randomized controlled trial

2015

Objectives We conducted a randomized trial among overweight long-distance drivers to study the effects of structured lifestyle counseling on body weight and cardiometabolic risk factors. Methods Men with waist circumference > 100 cm were randomized into a lifestyle counseling (LIFE, N=55) and a reference (REF, N=58) group. The LIFE group participated in monthly counseling on nutrition, physical activity, and sleep for 12 months aiming at 10% weight loss. After 12 months, the REF group participated in 3-month counseling. Assessments took place at 0, 12, and 24 months. Between-group differences in changes were analyzed by generalized linear modeling. Metabolic risk (Z score) was calculated fr…

Accumulation of sleep loss among shift-working truck drivers.

2021

Sleep loss is known to contribute to road traffic accidents. Professional drivers are vulnerable to curtailment of sleep due to long driving bouts and shift work. To fill in the gap in the literature related to the buildup of sleep loss in irregular shift systems, we recorded the sleep and working hours of 47 shift-working long-haul truck drivers during a two-week period. Sleep (time in bed) was verified by actigraphy and sleep logs. Sleepiness was measured using the Karolinska Sleepiness Scale (KSS). Individual sleep need was based on self-assessments. We examined the accumulated sleep versus self-reported sleep need across the study period, using midnights as points of observation, and th…

On-Road Study of Fatigue Management Strategies in Long-Haul Truck Drivers

2014

The current study investigated what strategies long-haul truck drivers use to mitigate fatigue at the wheel. A group of 52 truck drivers participated in the study in which drivers’ fatigue at the wheel was measured by a well-validated self-rating scale (the Karolinska Sleepiness Scale) and the use of fatigue countermeasures by a diary for a period of two consecutive workweeks including day and night-time trips. Results showed that the drivers more frequently used fatigue countermeasures while fatigued at the wheel but most of these countermeasures, with the exception of caffeine, can be regarded as inefficient (e.g., opening a window). The results indicate that long-haul truck drivers resp…

Behaviorally Induced Insufficient Sleep

2012

The self-reported stress and stressors in tram and long-haul truck drivers

2022

Work stress may compromise professional drivers’ health and driving capacity. Differences between driver groups in terms of on-duty stress are understudied. Therefore, we examined self-reported stress (Stockholm University Stress Scale) of shift-working tram and long-haul truck drivers (n = 75) across 2–3 weeks. Furthermore, stressors were self-reported retrospectively and categorised as related to the job, driving conditions, personal, or other causes. Stress levels were generally low, but moderate to high stress (≥6) was more frequently reported among the tram drivers. Stressors related to the job (54%) and driving conditions (19% of all shifts) were frequently reported among the tram and…

Prolonged sleep restriction induces changes in pathways involved in cholesterol metabolism and inflammatory responses

2016

Article

Lifestyle counseling in overweight truck and bus drivers : Effects on dietary patterns and physical activity

2016

We studied dietary patterns, physical activity (PA), and monthly goal setting in a weight reduction intervention in long-distance professional drivers. The study was conducted in Finland in 2009–2012. Male drivers with waist circumference > 100 cm were randomized to a lifestyle counseling (LIFE, N = 55) and a reference (REF, N = 58) group. During 12 months, LIFE participated in 6 face-to-face and 7 telephone counseling sessions on diet and PA. Dietary patterns were assessed using an index combining food diary and counselor interview, and PA with the number of daily steps using a pedometer. Monthly lifestyle goals, perceived facilitators and barriers, and adverse effects of PA in the LIFE pa…

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

2015

Driver sleepiness is a prevalent phenomenon among professional drivers working unconventional and irregular hours. For compromising occupational and traffic safety, sleepiness has become one of the major conundrums of road transportation. To further elucidate the phenomenon, an on-road study canvassing the under-explored relationship between working hours and sleepiness, sleep, and use of sleepiness countermeasures during and outside statutory rest breaks was conducted. Testing the association between the outcomes and working hours, generalized estimating equations models were fitted on a data collected from 54 long-haul truck drivers (mean 38.1 ± 10.5 years, one female) volunteering in the…

Mismatch negativity during objective and subjective sleepiness.

1997

The mismatch negativity (MMN) and P3 of auditory event-related potentials were studied during subjectively and objectively (physiologically) defined sleepiness under optimal stimulus conditions for MMN elicitation. The MMN and P3 were elicited by either small or large unattended auditory deviants presented to the left ear. The participant's task was to detect either rare auditory targets presented to the right ear or rare changes in the light flashes. Eleven young adults served as participants in a nighttime experiment. The MMN declined especially at Fz and Cz but not so markedly at the right mastoid as either subjective or objective alertness decreased. The amplitude of P3 also decreased d…

Precursors of the evoked K-complex in event-related brain potentials in stage 2 sleep.

1997

The aim of the study was to examine precursors of the evoked K-complex as manifested in event-related brain potentials (ERPs) during stage 2 sleep. ERPs to infrequent deviant tones of 1100 and 2000 Hz and immediately preceding frequent standard tones of 1000 Hz were compared between trials containing and trials not containing a K-complex (KC trials, NO KC trials, respectively) to the deviant tones. The N350 wave to the deviant tones was markedly larger during the KC than during the NO KC trials. Also the P210 wave to the 2000 Hz deviant tone showed the same phenomenon. No definite evidence was found for the mismatch negativity-like deflection during the KC trials. ERPs to the standard tones…

The Time-Varying Effect of Participatory Shift Scheduling on Working Hour Characteristics and Sickness Absence: Evidence from a Quasi-Experiment in H…

2022

Participatory shift scheduling for irregular working hours can influence shift schedules and sickness absence. We investigated the effects of using participatory shift scheduling and shift schedule evaluation tools on working hour characteristics and sickness absence. We utilized a panel data for 2015−2019 with 16,557 hospital employees (6143 in the intervention and 10,345 in the control group). Difference-in-differences regression with ward-level clustered standard errors was used to estimate the average treatment effect on the treated coefficients relative to timing of the intervention with 95% confidence intervals (CI). Using participatory scheduling tool increased long working hou…

Effects of cumulative sleep restriction on self-perceptions while multitasking

2012

Summary This study addressed a rarely studied question of self-perceptions of performance and overall functional state during cumulative sleep restriction and the ensuing recovery period. Twenty healthy male volunteers, aged 19–29 years, were divided into a sleep restriction group (n = 13) and a control group (n = 7). On the first 2 nights, the sleep restriction group had an 8-h sleep opportunity that was restricted to 4 h for the next 5 nights, and then restored to 8 h for the last 2 nights. The control group had an 8-h sleep opportunity each night. Each day participants accomplished 50-min multitask sessions and gave self-ratings in their connection. Similar to our previous findings on mu…

Self-reported sleep duration and cognitive functioning in the general population

2009

This study investigated the relationship between self-reported sleep factors (sleep duration, insomnia, use of sleeping medicine, probable sleep apnoea and feelings of fatigue and tiredness) with cognitive functioning in 5177 people aged 30 years or older from a cross-sectional representative sample of the adult population in Finland (The Finnish Health 2000 Survey). Previous studies have indicated a U-shaped association between increased health risks and sleep duration; we hypothesized a U-shaped association between sleep duration and cognitive functioning. Objective cognitive functioning was assessed with tasks derived from the Consortium to Establish a Registry for Alzheimer's Disease te…

Sleep and alertness in shift work disorder: findings of a field study

2018

Purpose Although shift work disorder (SWD) affects a major part of the shift working population, little is known about its manifestation in real life. This observational field study aimed to provide a detailed picture of sleep and alertness among shift workers with a questionnaire-based SWD, by comparing them to shift workers without SWD during work shifts and free time. Methods SWD was determined by a questionnaire. Questionnaires and 3-week field monitoring, including sleep diaries, actigraphy, the Karolinska Sleepiness Scale (KSS), EEG-based sleep recordings, and Psychomotor Vigilance Tasks (PVT), were used to study 22 SWD cases and 9 non-SWD workers. Results The SWD group had a shorter …

Estimating brain load from the EEG.

2009

Modern work requires cognitively demanding multitasking and the need for sustained vigilance, which may result in work-related stress and may increase the possibility of human error. Objective methods for estimating cognitive overload and mental fatigue of the brain on-line, during work performance, are needed. We present a two-channel electroencephalography (EEG)–based index, theta Fz/alpha Pz ratio, potentially implementable into a compact wearable device. The index reacts to both acute external and cumulative internal load. The index increased with the number of tasks to be performed concurrently (p= 0.004) and with increased time awake, both after normal sleep (p= 0.002) and sleep restr…

Cognitive behavioral therapy for chronic insomnia inoccupationalhealth services: Analyses of outcomes upto24monthspost-treatment

2013

Abstract Objective Cognitive behavioral therapy for insomnia (CBT-I) is an effective treatment for persistent insomnia. The purpose of this study was to examine the effectiveness of and response patterns to CBT-I among daytime and shift workers with insomnia over a 24-month follow-up in occupational health services (OHS). Methods The participants were 59 media workers with chronic insomnia, of whom 69% were reached at 24-month follow-up. Sleep diaries and questionnaires over seven measurement points were used as outcomes. Trained OHS nurses led the CBT-I groups. The study design was a non-randomized group intervention. Results Self-perceived severity of insomnia, sleep-related dysfunctional…

Processing of auditory stimuli during tonic and phasic periods of REM sleep as revealed by event-related brain potentials

1996

The brain has been reported to be more preoccupied with dreams during phasic than during tonic REM sleep. Whether these periods also differ in terms of the processing of external stimuli was examined. Event-related brain potentials (ERPs) to a frequent standard tone of 1000 Hz (P = 97%) and infrequent deviant tones of 1100 and 2000 Hz (P = 1.5% for each) were recorded (n = 13) during wakefulness and nocturnal sleep. An ERP wave (called REM-P3) resembling a waking P3 wave was larger for the 2000 Hz deviant during tonic than during phasic REM sleep. Also the P210 wave was larger during tonic than during phasic REM sleep. A reliable mismatch negativity component appeared only in wakefulness. I…

Sleep, alertness and alertness management among commercial airline pilots on short-haul and long-haul flights

2016

Item does not contain fulltext Airline pilots' sleep and on-duty alertness are important focus areas in commercial aviation. Until now, studies pertaining to this topic have mainly focused on specific characteristics of flights and thus a comprehensive picture of the matter is not well established. In addition, research knowledge of what airline pilots actually do to maintain their alertness while being on duty is scarce. To address these gaps in research knowledge, we conducted a field study on a representative sample of the airline pilots of a medium-sized airline. The sample consisted of 90 pilots, of whom 30 flew long-haul (LH) routes, 30 short-haul (SH) routes, and 30 flew both. A tota…

Are long-haul truck drivers unusually alert? A comparison with long-haul airline pilots.

2020

Abstract Background Recent studies suggest heavy vehicle drivers self-estimate their sleepiness unexpectedly low during night duties. The present study compared sleepiness ratings of long-haul truck drivers with those of long-haul airline pilots during night and non-night duties. In addition, the correspondence between self-rated manifest and predicted latent sleepiness was examined in the two groups. Methods Twenty-two drivers and 33 pilots participated. Their working hours, sleep, on-duty sleepiness, and use of sleepiness countermeasures were measured in naturalistic conditions. Predictions of latent sleepiness were based on the measurements of working hours and sleep using the Sleep/Wake…

Psychomotor slowness is associated with self-reported sleep duration among the general population

2010

Short and long self‐reported sleep durations have been found to be associated with several seemingly disparate health risks and impaired functional abilities, including cognitive functioning. The role of long sleep is especially poorly understood in this context. Psychomotor slowness, shown to have analogous associations with cognitive performance and health risks as self‐reported long sleep duration, has not been studied together with sleep duration in epidemiological settings. We hypothesized that self‐reported habitual sleep duration, especially long sleep, is associated with slow psychomotor reaction time, and that this association is independent of vigilance‐related factors. The hypoth…

Partial Sleep Restriction Activates Immune Response-Related Gene Expression Pathways: Experimental and Epidemiological Studies in Humans

2013

Epidemiological studies have shown that short or insufficient sleep is associated with increased risk for metabolic diseases and mortality. To elucidate mechanisms behind this connection, we aimed to identify genes and pathways affected by experimentally induced, partial sleep restriction and to verify their connection to insufficient sleep at population level. The experimental design simulated sleep restriction during a working week: sleep of healthy men (N = 9) was restricted to 4 h/night for five nights. The control subjects (N = 4) spent 8 h/night in bed. Leukocyte RNA expression was analyzed at baseline, after sleep restriction, and after recovery using whole genome microarrays complem…

The self-reported causes of sleepiness in shift-working tram and truck drivers

2021

Identifying the causes of sleepiness in various safety-critical work environments is neces-sary for implementing more efficient fatigue management strategies. In transportation, little is known about drivers' own perceptions of these causes. Therefore, we instructed shift-working tram (n = 23) and long-haul truck drivers (n = 52) to report at the end of their shifts what made them sleepy if they felt so. These self-reports, measured on-duty sleepiness, and sleep amounts were recorded on every shift over a period of 2-3 weeks per driver. The causes of sleepiness were queried with smartphone applications and sleep logs. Sleepiness was measured with the Karolinska Sleepiness Scale (KSS) and sl…

Physiological and autonomic stress responses after prolonged sleep restriction and subsequent recovery sleep in healthy young men

2018

Purpose Sleep restriction is increasingly common and associated with the development of health problems. We investigated how the neuroendocrine stress systems respond to prolonged sleep restriction and subsequent recovery sleep in healthy young men. Methods After two baseline (BL) nights of 8 h time in bed (TIB), TIB was restricted to 4 h per night for five nights (sleep restriction, SR, n = 15), followed by three recovery nights (REC) of 8 h TIB, representing a busy workweek and a recovery weekend. The control group (n = 8) had 8 h TIB throughout the experiment. A variety of autonomic cardiovascular parameters, together with salivary neuropeptide Y (NPY) and cortisol levels, were assessed.…

Cognitive behavioral therapy for shift workers with chronic insomnia

2012

Abstract Objective Shift work is a challenge in the screening and treatment of chronic insomnia. The aim of this study was to examine the implementation and effectiveness of a cognitive behavioral group intervention for insomnia (CBT-I) among shift workers with chronic insomnia. We also studied whether insomnia symptoms and intervention effects differed on work days and days off. Methods The study design was a non-randomized group intervention, including a waiting period prior to CBT-I as a control condition. A total of 19 media workers who worked irregular hours and had non-organic insomnia with features of psychological insomnia completed the study. We followed up with the results for a p…

Accumulation of sleep loss among shift-working truck drivers

2021

Sleep loss is known to contribute to road traffic accidents. Professional drivers are vulnerable to curtailment of sleep due to long driving bouts and shift work. To fill in the gap in the literature related to the buildup of sleep loss in irregular shift systems, we recorded the sleep and working hours of 47 shift-working long-haul truck drivers during a two-week period. Sleep (time in bed) was verified by actigraphy and sleep logs. Sleepiness was measured using the Karolinska Sleepiness Scale (KSS). Individual sleep need was based on self-assessments. We examined the accumulated sleep versus self-reported sleep need across the study period, using midnights as points of observation, and th…

Kyky toimia arvossaan turvallisuusaloilla

2023

Turvallisuusalojen henkilöstön fyysisen toimintakyvyn ylläpito korostuu Euroopan kiristyneessä turvallisuustilanteessa. nonPeerReviewed