Psychosocial Work Characteristics Predicting Daytime Sleepiness in Day and Shift Workers

Characteristics of work organization other than working time arrangements may contribute importantly to daytime sleepiness. The present study was designed to identify the psychosocial factors at work that predict daytime sleepiness in a sample of day and shift workers. Participants working at a pulp and chemical factory completed an annual questionnaire regarding psychosocial factors at work using the U.S. National Institute for Occupational Safety and Health Generic Job Stress Questionnaire (i.e., quantitative workload, variance in workload, job control, support from supervisor, coworkers, or family/friends, job satisfaction, and depressive symptoms), as well as daytime sleepiness (through the Epworth Sleepiness Scale [ESS]) and sleep disturbances for three years starting in 2002 (response rates, 94.6–99.0%). The present analysis included 55 day workers (11 women) and 57 shift workers (all men) who participated in all three years of the study, worked under the same work schedule throughout the study period, and had no missing data on any of the daytime sleep items. A repeated‐measures analysis of covariance (ANCOVA) was used to test the effects of work schedule (day vs. shift work) and psychosocial factors at work in 2002 on the ESS scores in subsequent years, with sleep duration, insomnia symptoms, chronic diseases, and sleepiness levels at baseline as covariates. Given significant and near‐significant interactions of work schedules with psychosocial factor or study year, the ANCOVA, with the factors of psychosocial work characteristics and study year, was performed by type of work schedule. The results indicated a significant main effect of psychosocial work characteristics (p=0.010, partial ?²=0.14) and an almost significant main effect of study year (p=0.067, partial ?²=0.06) and interaction between psychosocial work characteristics and study year (p=0.085, partial ?²=0.06) for variance in workload among the day work group. The day workers reporting high variance in workload in 2002 exhibited significantly higher ESS scores in 2003 and 2004 than did those reporting low variance in workload. The ANCOVA for the shift work group showed a main effect of psychosocial work characteristics for job satisfaction (p=0.026, partial ?²=0.10) and depressive symptoms (p=0.094, partial ?²=0.06) with the interaction between psychosocial work characteristics and study year for job satisfaction (p=0.172, partial ?²=0.04) and depressive symptoms (p=0.035, partial ?²=0.07). The shift workers with low job satisfaction and high symptoms of depression in 2002 showed significantly greater ESS scores in 2003 and/or 2004 than did those with opposite characteristics. These results may suggest a potential predictive value of variance in workload for day workers as well as job satisfaction and depressive symptoms for shift workers with respect to daytime sleepiness. The present findings may imply that redesigning these aspects of work environment would be of help in managing daytime sleepiness.     

Association of sickness absence with poor sleep and depressive symptoms in shift workers

A cross-sectional study was conducted to evaluate the contribution of daily sleep habits and depressive symptoms to sickness absences of shift workers. A self-administered questionnaire that solicited answers about sleep, symptoms of depression, sickness absence, diseases/injuries, and lifestyle factors was submitted to a sample of 522 rotating shift workers between the ages of 18-59 (mean 27) yrs of an electric equipment manufacturing company. The seven features of sleep queried were daily hours of sleep, time to fall asleep, awakening during sleep, early morning awakening, sleep well at night, sufficiency of sleep, and excessive daytime sleepiness at work. The responses were assessed over the subject's previous 1-yr period. Each sleep feature, except daily sleeping hours, was dichotomized by the following responses: (1) taking more than 30min to fall asleep (difficulty initiating sleep; DIS), (2) awakening during sleep almost every day (difficulty maintaining sleep; DMS), (3) early morning awakening almost every day (EMA), (4) sleeping very poorly or not so well at night, (5) definite or somewhat insufficient nightly sleep, and (6) excessive daytime sleepiness at work almost every day (EDS). Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) scale. Sickness absence was calculated by asking subjects "How many days in total have you been absent from work due to sickness, including paid vacation, in the last 1-yr period?" The responses were divided into three groups that included no (0 days) sickness absences (reference group, n=235 subjects), 1 to 4 days (short-term, n=199 subjects), and 5 days or more (long-term, n = 88 subjects). Compared to the prevalence of sleep features of the reference group, workers with short-term absence showed a significantly higher prevalence of EMA with an odds ratio (OR) of 5.3, 95% confidence interval (CI) 1.3-22.0. Long-term absence was significantly associated with DMS (OR = 2.1, 95%CI 1.0-4.6), EMA (OR = 5.6, 95%CI 1.0-28.7), sleeping poorly at night (OR= 2.6, 95%CI 1.4-5.0), and high depressive symptoms (OR = 2.0, 95%CI 1.0-3.7) according to the CES-D score of >16, after adjusting for multiple confounding variables. These data point to an association between both the parameters of poor sleep and symptoms of deep depression when self-reported sickness absence is frequent. The association is particularly strong with long-term absence in male shift workers.     

Association of Sickness Absence with Poor Sleep and Depressive Symptoms in Shift Workers

A cross-sectional study was conducted to evaluate the contribution of daily sleep habits and depressive symptoms to sickness absences of shift workers. A self-administered questionnaire that solicited answers about sleep, symptoms of depression, sickness absence, diseases/injuries, and lifestyle factors was submitted to a sample of 522 rotating shift workers between the ages of 18–59 (mean 27) yrs of an electric equipment manufacturing company. The seven features of sleep queried were daily hours of sleep, time to fall asleep, awakening during sleep, early morning awakening, sleep well at night, sufficiency of sleep, and excessive daytime sleepiness at work. The responses were assessed over the subject's previous 1-yr period. Each sleep feature, except daily sleeping hours, was dichotomized by the following responses: (1) taking more than 30 min to fall asleep (difficulty initiating sleep; DIS), (2) awakening during sleep almost every day (difficulty maintaining sleep; DMS), (3) early morning awakening almost every day (EMA), (4) sleeping very poorly or not so well at night, (5) definite or somewhat insufficient nightly sleep, and (6) excessive daytime sleepiness at work almost every day (EDS). Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) scale. Sickness absence was calculated by asking subjects “How many days in total have you been absent from work due to sickness, including paid vacation, in the last 1-yr period?” The responses were divided into three groups that included no (0 days) sickness absences (reference group, n = 235 subjects), 1 to 4 days (short-term, n = 199 subjects), and 5 days or more (long-term, n = 88 subjects). Compared to the prevalence of sleep features of the reference group, workers with short-term absence showed a significantly higher prevalence of EMA with an odds ratio (OR) of 5.3, 95% confidence interval (CI) 1.3–22.0. Long-term absence was significantly associated with DMS (OR = 2.1, 95%CI 1.0–4.6), EMA (OR = 5.6, 95%CI 1.0–28.7), sleeping poorly at night (OR = 2.6, 95%CI 1.4–5.0), and high depressive symptoms (OR = 2.0, 95%CI 1.0–3.7) according to the CES-D score of ≥16, after adjusting for multiple confounding variables. These data point to an association between both the parameters of poor sleep and symptoms of deep depression when self-reported sickness absence is frequent. The association is particularly strong with long-term absence in male shift workers.     

Factors associated with sleep duration in Brazilian high school students

The aim of this study was to investigate the factors associated with short sleep duration on southern Brazilian high school students. Our study was comprised of 1,132 adolescents aged 14 to 19 years, enrolled in public high schools in São José, Brazil. The students answered a questionnaire about working (work and workload), health perception, smoking, school schedule, sleep (duration and daytime sleepiness), and socio-demographics data. The results showed that more than two thirds of adolescent workers had short sleep duration (76.7%), and those with a higher workload (more than 20 hours) had a shorter sleep duration (7.07 hours) compared to non-workers (7.83 hours). In the analysis of factors associated with short sleep duration, adolescents who worked (OR = 2.12, 95% CI 1.53 to 2.95) were more likely to have short sleep duration compared to those who did not work. In addition, older adolescents (17–19 years) and students with poor sleep quality were 40% and 55% more likely to have short sleep duration compared to younger adolescents (14–16 years) and students with good sleep quality, respectively. Adolescents with daytime sleepiness were more likely to have short sleep duration (OR = 1.49, 95% CI 1.06 to 2.07) compared to those without excessive daytime sleepiness. In addition students of the morning shift (OR = 6.02, 95% CI 4.23 to 8.57) and evening shift (OR = 2.16, 95% CI 1.45 to 3.22) were more likely to have short sleep duration compared to adolescents of the afternoon shift. Thereby adolescents who are workers, older, attended morning and evening classes and have excessive daytime sleepiness showed risk factors for short sleep duration. In this sense, it is pointed out the importance of raising awareness of these risk factors for short sleep duration of students from public schools from São José, located in southern Brazil.     

Daytime sleepiness in the obese: not as simple as obstructive sleep apnea

Objective: Excessive daytime sleepiness is a common symptom in obese patients, but what drives this condition is unclear. The objective was to look for clinical, anthropometric, biochemical, and polysomnographic predictors of excessive daytime sleepiness as measured by the Epworth Sleepiness Scale (ESS) in obese patients. Research Methods and Procedures: The ESS questionnaire was completed by 1055 consecutive patients presenting for obesity surgery. Those at high risk for obstructive sleep apnea (n = 331) had diagnostic overnight polysomnography preoperatively. All patients had preoperative clinical, hematologic, and biochemical measurements and completed multiple questionnaires. Results: There was no significant relationship between ESS score and any measure of diagnostic polysomnography factors, including total apnea hypopnea index. Subtle increases in ESS scores were reported in men, older patients, and those with type 2 diabetes. However, general demographic, anthropometric, and biochemical measures of the metabolic syndrome explained only 3% of ESS score variance, and inflammatory markers of C‐reactive protein and total white cell count were not predictive. Poor Short Form‐36 energy scores (b = ?0.18, p < 0.001) and high Beck Depression Inventory scores were predictive of higher ESS scores (b = 0.15, p < 0.001) and, along with increasing age and male gender, explained 10% of variance. Symptoms related to disturbed nocturnal sleep explained 30% of variance. Conclusion: In severely obese subjects, increased daytime sleepiness does not seem to be driven by obstructive sleep apnea, the degree of obesity, or anthropometric, metabolic, or inflammatory markers of the metabolic syndrome. It is, however, associated with poor energy, symptoms of depression, and symptoms of nocturnal sleep disturbance.     

Shift work and depressive symptoms: the mediating effect of vitamin D and sleep quality

Shift work is associated with vitamin D level, sleep quality, and depressive symptoms. Vitamin D and sleep quality are also associated with depressive symptoms. The purpose of this study was to compare vitamin D level, sleep quality, and depressive symptoms between shift workers and daytime workers and analyze the mediating effect of vitamin D and sleep quality between shift work and depressive symptoms. Among those who participated in the Kangbuk Samsung Health Study in 2012 and 2014, 82,078 cases of full-time workers were analyzed. We evaluated their shift work, vitamin D level, sleep quality, and depressive symptoms with blood samples and questionnaires. Chi-square tests, t-tests, and path statistical analysis were performed. More depressive symptoms, lower vitamin D levels, and poorer sleep quality were associated with shift work. According to a path analysis, shift work had both a direct effect and an indirect effect on depressive symptoms, each mediated by sleep quality and vitamin D level. When a multigroup analysis was conducted for each sex, paths containing sleep quality were more significant in female shift workers than male shift workers; paths involving vitamin D did not differ between sexes. To assess depression risk in shift workers, evaluating vitamin D level and sleep quality is essential. Also, sleep problems are more prevalent in female compared to male shift workers with respect depression prevalence.     

Association between depressive symptoms and morningness-eveningness,sleep duration and rotating shift work in Japanese nurses

Higher depressive symptoms have been reported in rotating shift workers compared with day workers. Depressive symptoms in adults who do not engage in night work have also been shown to be associated with chronotype and sleep duration. This study examines associations between depressive symptoms, morningness-eveningness (i.e. the degree to which people prefer to be active in the morning or the evening), sleep duration and rotating shift work. Japanese nurses (1252 day workers and 1780 rotating shift workers, aged 20–59) were studied using a self-administered questionnaire. The questionnaire covered depressive symptoms, morningness-eveningness, sleep habits and demographic characteristics of the participants. The Center for Epidemiologic Studies Depression Scale (CES-D) was used to determine the levels of depressive symptoms. A Japanese version of the Morningness-Eveningness Questionnaire (MEQ) was used to measure morningness-eveningness. The CES-D score of shift workers was significantly (p < 0.05) higher than that of day workers. The MEQ score was significantly (p < 0.05) lower (i.e. greater eveningness) in shift workers than in day workers. Sleep duration on the day shift was significantly (p < 0.05) shorter in shift workers than in day workers. Simple linear regression revealed that the MEQ score, sleep duration on the day shift and current work shift (i.e. rotating shift work) were significantly (p < 0.05) associated with the CES-D score. Multivariate linear regression indicated that greater eveningness and shorter sleep duration were independently associated with higher CES-D scores, while rotating shift work was not. These associations between the MEQ score, the sleep duration and the CES-D score were also confirmed in both day workers and shift workers when the groups were analyzed separately. These results suggest that greater eveningness and shorter sleep duration on the day shift were independently associated with higher levels of depressive symptoms, which may explain associations between rotating shift workers and depressive symptoms. These findings have important implications for the development of novel strategies for preventing poor mental health in day workers and rotating shift workers.     

Job stress, social support at work, and insomnia in Japanese shift workers

A cross-sectional study was conducted to clarify the contribution of psychological job stress to insomnia in shift workers. A self-administered questionnaire concerning job stress, sleep, depressive symptoms and lifestyle factors was submitted to a sample of 530 rotating shift workers of age 18-59 years (mean age 27) in an electric equipment manufacturing company. Perceived job stress, i.e., job demands, job control and social support at work, was assessed using the Japanese version of the Job Content Questionnaire. Insomnia was regarded as prevalent if the workers had at least one of the following symptoms in the last year; less than 30 minutes to fall asleep, difficulty in maintaining sleep, or early morning awakening almost everyday. Overall prevalence was 37.8%. Logistic regression analyses while adjusting relevant factors showed that lower social support at work was significantly associated with a greater risk of insomnia than the higher social support (adjusted OR 2.5). Higher job strain with lower social support at work increased the risk, compared to lower strain with higher support at work (crude OR 1.8; adjusted OR 1.5). Our findings suggest the low social support at work independently associated with insomnia in shift workers.     

Trajectories of sleepiness and insomnia symptoms in Norwegian nurses with and without night work and rotational work

Numerous cross-sectional studies report high prevalence rates of sleepiness and insomnia in shift workers, but few longitudinal studies exist. We investigated trajectories of sleepiness and insomnia symptoms in a sample of Norwegian nurses across four measurements, spanning a total of four years (sleepiness) and five years (insomnia). The participants completed the Epworth Sleepiness Scale and the Bergen Insomnia Scale at each measurement instance. Latent growth curve models were used to analyse the data. Separate models examined night work (night work, entering and leaving night work) and rotational work (rotational work, entering and leaving rotational work) as predictors for trajectories of sleepiness and insomnia symptoms, respectively. Baseline values of sleepiness and insomnia were higher among rotational shift workers than among workers with fixed shifts (day or night). The results showed that night work throughout the period and entering night work during the period were not associated with different trajectories of sleepiness or insomnia symptoms, compared to not having night work. The same results were found for rotational work and entering rotational work, compared to not having rotational work. Leaving night work and leaving rotational work were associated with a decrease in sleepiness and insomnia symptoms, compared to staying in such work.     

Sleep on the job partially compensates for sleep loss in night-shift nurses

Nursing personnel in Brazil are usually submitted to fixed 12 h shifts with no consecutive working days or nights. Moonlighting is common in this group, with a consequent increase in the number of working hours. The possibility of sleeping on the job during the night shift in the studied hospitals had already been described. The present study aims to analyze whether the time devoted to daily activities (sleep, rest, leisure, housework, commuting, personal needs, care of children or other people, non-paid work, and study) is related to the number of worked hours and to nap-taking during the night shift. The field study took place at two public hospitals in Rio de Janeiro, Brazil. Workers filled out a structured form on time devoted to the above-mentioned activities for at least four consecutive days. The time devoted to sleep was analyzed according to its occurrence at home or on the job. Workers were classified according to the number of jobs (one job/two jobs) and the time dedicated to work according to the median of the whole series (below the median/above the median). All workers who had at least one working night were analyzed as to nap-taking on the job. They were classified according to the sleep occurrence during the night shift-the sleep group and the non-sleep group, both of which were compared to daytime workers. Statistical treatment of data included non-parametrical procedures. The study group comprised 144 workers (mean age: 35.7+/-10.5 years old; 91% women; 78% nurse assistants, the remainder registered nurses). They recorded their daily activities for 4-11 days; 829 cumulative days were analyzed for the whole group. A total of 165 working nights were analyzed; sleep or rest occurred during 112 (68%) of them, with mean sleep/rest duration of 141+/-86 min. Time devoted to sleep and leisure varied according to the number of working hours, being significantly reduced in those submitted to longer work hours (p < 0.001 and p = 0.002, respectively). Results close to significance point to a reduction in the time dedicated to housework among workers with long work hours (p = 0.053). The time spent on sleep/rest per working night did not differ according to the number of worked hours (p = 0.490). A tendency was observed for those who have two jobs to devote more time to sleep/rest on the job (p = 0.058). The time of personal needs was significantly lower among those who did not sleep on the job as compared to day workers (p = 0.036). The total sleep time was significantly lower among those who did not sleep on the job, as compared to day workers and to those who slept on the job (p = 0.004 and p = 0.05, respectively). As to home sleep length, workers who slept and those who did not sleep on the job were similar and slept significantly less than exclusively daytime workers (p < 0.001 and p = 0.002, respectively). Sleeping on the job during the night shift seems to partially compensate for the shorter sleep at home among night workers and may play a beneficial effect in coping with two jobs.     

Daytime Sleepiness in Parkinson’s Disease: A Reappraisal

Background

Excessive daytime sleepiness is a frequent complaint in Parkinson’s disease (PD); however the frequency and risk factors for objective sleepiness remain mostly unknown. We investigated both the frequency and determinants of self-reported and objective daytime sleepiness in patients with Parkinson’s disease (PD) using a wide range of potential predictors.

Methods

One hundred and thirty four consecutive patients with PD, without selection bias for sleep complaint, underwent a semi-structured clinical interview and a one night polysomnography followed by a multiple sleep latency test (MSLT). Demographic characteristics, medical history, PD course and severity, daytime sleepiness, depressive and insomnia symptoms, treatment intake, pain, restless legs syndrome, REM sleep behaviour disorder, and nighttime sleep measures were collected. Self-reported daytime sleepiness was defined by an Epworth Sleepiness Scale (ESS) score above 10. A mean sleep latency on MSLT below 8 minutes defined objective daytime sleepiness.

Results

Of 134 patients with PD, 46.3% had subjective and only 13.4% had objective sleepiness with a weak negative correlation between ESS and MSLT latency. A high body mass index (BMI) was associated with both ESS and MSLT, a pain complaint with ESS, and a higher apnea/hypopnea index with MSLT. However, no associations were found between both objective and subjective sleepiness, and measures of motor disability, disease onset, medication (type and dose), depression, insomnia, restless legs syndrome, REM sleep behaviour disorder and nighttime sleep evaluation.

Conclusion

We found a high frequency of self-reported EDS in PD, a finding which is however not confirmed by the gold standard neurophysiological evaluation. Current treatment options for EDS in PD are very limited; it thus remains to be determined whether decreasing pain and BMI in association with the treatment of sleep apnea syndrome would decrease significantly daytime sleepiness in PD.     

Effects of Shift Work on the Postural and Psychomotor Performance of Night Workers

The purpose of the study was to investigate the effects of shift work on the psychomotor and postural performance of night workers. The study included 20 polysomnography technicians working schedule of 12-h night shift by 36-h off. On the first day of protocol, the body mass and height were measured, and an actigraph was placed on the wrist of each participant. On the second day of protocol, sleepiness by Karolinska Sleepiness Scale, postural control by force platform (30 seconds) and psychomotor performance by Psychomotor Vigilance Task (10 minutes) were measured before and after 12-h night work. Results showed that after 12-h night work, sleepiness increased by 59% (p<0.001), postural control variables increased by 9% (p = 0.048), and 14% (p = 0.006). Mean reaction time, and the number of lapses of attention increased by 13% (p = 0.006) and 425% (p = 0.015), respectively, but the mean reciprocal reaction time decreased by 7%. In addition, there were correlations between sleepiness and postural control variables with opened eyes (r = 0.616, 95% confidence interval [CI] = 0.361–0.815; r = 0.538; 95% CI = 0.280–0.748) and closed eyes (r = 0.557; 95% CI = 0.304–0.764, r = 0497; 95% CI = 0.325–0.715) and a pronounced effect of sleepiness on postural sway (R² = 0.393; 95% CI = 0.001–0.03). Therefore, 12-h night work system and sleepiness showed a negative impact in postural and psychomotor vigilance performance of night workers. As unexpected, the force platform was feasibility to detect sleepiness in this population, underscoring the possibility of using this method in the workplace to prevent occupational injuries and accidents.     

Symptoms In Patients With Primary Hyperparathyroidism: Muscle Weakness Or Sleepiness

ObjectiveTo evaluate the effects of parathyroidectomy on the nonspecific symptoms associated with primary hyperparathyroidism, with an emphasis on distinguishing sleepiness from muscle weakness.MethodsWe conducted a prospective cohort study of consecutive patients presenting for parathyroidectomy for the treatment of primary hyperparathyroidism. Twenty-three patients underwent assessment preopera tively and postoperatively. The Functional Outcomes of Sleep Questionnaire (FOSQ), the Epworth Sleepiness Scale (ESS), and a questionnaire of disease-specific symptoms were administered preoperatively, 2 weeks postoperatively, and 4 to 6 months postoperatively. The FOSQ assesses how sleepiness alters daytime performance, and the ESS reflects the degree of daytime sleepiness.ResultsAll 23 patients achieved normocalcemia postoperatively. Although no significant changes were found in the overall scores for the FOSQ and ESS after parathyroidectomy, there was a significant decline in the overall mean incidence of disease-specific symptoms postoperatively (P<0.0001 after 2 weeks and P= 0.0020 after 4 to 6 months). The five disease-specific symptoms that significantly decreased in frequency postoperatively were (1) muscle weakness, (2) polydipsia, (3)dry skin and itching, (4) memory loss, and (5) anxiety.ConclusionIn this study, patients with primary hyperparathyroidism did not demonstrate daytime sleepiness or difficulty performing everyday activities because of sleepiness at baseline or after successful parathyroidectomy. The overall mean percentage for incidence of disease-specific symptoms, however, significantly declined postoperatively, especially in reference to muscle weakness. (Endocr Pract. 2004;10:404-408)     

Sleep Disturbances Among Female Nurses: Comparing Shift to Day Work

Recently, attention has focused in Israel on the possible legal and health consequences of shift work. We decided to study sleep disorders among female nursing personnel working a shift schedule, in comparison with day nurses, in a large metropolitan general hospital. The study population was composed of 131 female certified nurses working shifts and 44 working days only. Inclusion criteria for the survey was at least 1 year of shift work alternating between day, evening, and night shifts, or at least 1 year of day work. All participants completed a self-report sleep questionnaire encompassing (a) demographic data, (b) sleep survey, and (c) employment details. Statistical analysis was performed using the Pearson correlation test and analysis of variance multiple range test (according to Scheffe's procedure). No significant correlation was found between sleep disorders and age of subjects. No sleep disorders were reported by 19.8% of shift workers versus 76.5% of day workers. Statistically significant findings were that the number of shifts per week >4.1 (p = 0.001) and duration of shift work >13.6 years (p = 0.007) correlated with the presence of sleep disorders. An additional significant finding (p = 0.014) was the impact of evening shifts on sleep disorders. The present small study confined to women supports the growing body of data on sleep complaints among shift workers.     

Factors affecting work ability in day and shift-working nurses

Satisfactory work ability is sustained and promoted by good physical and mental health and by favorable working conditions. This study examined whether favorable and rewarding work-related factors increased the work ability among European nurses. The study sample was drawn from the Nurses' Early Exit Study and consisted of 7,516 nursing staff from seven European countries working in state-owned and private hospitals. In all, 10.8% were day, 4.2% were permanent night, 20.9% were shift without night shift, and 64.1% were shift workers with night shifts. Participants were administered a composite questionnaire at baseline (Time 0) and 1 yr later (Time 1). The Work Ability Index (WAI) at Time 1 was used as the outcome measure, while work schedule, sleep, rewards (esteem and career), satisfaction with pay, work involvement and motivation, and satisfaction with working hours at Time 0 were included as potential determinants of work ability. Univariate and multivariate analyses were conducted after adjusting for a number of confounders (i.e., country, age, sex, type of employment, family status, and other job opportunities in the same area). Work schedule was not related to Time 1 changes in WAI. Higher sleep quality and quantity and more favorable psychosocial factors significantly increased work ability levels. Higher sleep quality and quantity did not mediate the effect of work schedule on work ability. No relevant interaction effects on work ability were observed between work schedule and the other factors considered at Time 0. As a whole, sleep and satisfaction with working time were gradually reduced from day work to permanent night work. However, scores on work involvement, motivation, and satisfaction with pay and rewards were the highest in permanent night workers and the lowest in rotating shift workers that included night shifts.     

Factors Affecting Work Ability in Day and Shift‐Working Nurses

Satisfactory work ability is sustained and promoted by good physical and mental health and by favorable working conditions. This study examined whether favorable and rewarding work‐related factors increased the work ability among European nurses. The study sample was drawn from the Nurses' Early Exit Study and consisted of 7,516 nursing staff from seven European countries working in state‐owned and private hospitals. In all, 10.8% were day, 4.2% were permanent night, 20.9% were shift without night shift, and 64.1% were shift workers with night shifts. Participants were administered a composite questionnaire at baseline (Time 0) and 1 yr later (Time 1). The Work Ability Index (WAI) at Time 1 was used as the outcome measure, while work schedule, sleep, rewards (esteem and career), satisfaction with pay, work involvement and motivation, and satisfaction with working hours at Time 0 were included as potential determinants of work ability. Univariate and multivariate analyses were conducted after adjusting for a number of confounders (i.e., country, age, sex, type of employment, family status, and other job opportunities in the same area). Work schedule was not related to Time 1 changes in WAI. Higher sleep quality and quantity and more favorable psychosocial factors significantly increased work ability levels. Higher sleep quality and quantity did not mediate the effect of work schedule on work ability. No relevant interaction effects on work ability were observed between work schedule and the other factors considered at Time 0. As a whole, sleep and satisfaction with working time were gradually reduced from day work to permanent night work. However, scores on work involvement, motivation, and satisfaction with pay and rewards were the highest in permanent night workers and the lowest in rotating shift workers that included night shifts.     

Perceived sleep quality among edentulous elders

doi: 10.1111/j.1741‐2358.2010.00426.x Perceived sleep quality among edentulous elders Background: Anatomical changes associated with edentulism are thought to disturb seniors’ sleep. Objectives: (1) To determine sleep quality and daytime sleepiness of edentulous elders. (2) To examine the association between oral health‐related quality of life and sleep quality. Methods: Data were collected at a 1‐year follow‐up from 173 healthy edentulous elders who had participated in a randomised controlled trial and randomly received two types of mandibular prosthesis. Subjective sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI, range 0–21), with higher scores indicating poorer sleep quality. The Epworth Sleepiness Scale (ESS) was used to measure the level of perceived daytime sleepiness, and scores ≥10 indicated sleepiness. Results: The mean global PSQI and ESS scores were 4.7 ± 3.5 and 5.3 ± 3.9. There were no differences in sleep quality or sleepiness between those who wore their dentures at night and those who did not. Elders with frequent denture problems were sleepier during the day than those with fewer problems (p = 0.0034). General health (p = 0.02) and oral health‐related quality of life (p = 0.001) are significant predictors of sleep quality. Conclusion: Healthy edentulous elders, independent of nocturnal wearing of their prosthesis, are good sleepers. Maintaining high oral health quality of life could contribute to better sleep.     

Sleep parameters among offshore workers: an initial assessment in the Campos Basin, Rio De Janeiro, Brazil

Shift work has potentially adverse effects on health, particularly on sleep. The purpose of the present study was to assess sleep parameters among personnel working in oil and gas offshore installations in the Campos Basin, Rio de Janeiro, Brazil. One hundred and seventy-nine subjects were asked to complete a sleep questionnaire with multiple-choice answers. Offshore workers were divided into two groups according to their work schedule: (1) fixed daytime workers (n = 86; age: 35.8+/-9.6 yrs) and (2) shift (n = 87) or night (n = 6) workers (total n = 93; age: 37.7+/-9.7 yrs). Shift/night workers reported poor sleep more frequently than the daytime workers (20.4% vs. 1.2%, p < 0.01), as well as habitual difficulty in falling asleep (15.1% vs. 4.7%, p<0.01), long latency of sleep onset (28% vs. 7%, p<0.01), fragmented sleep (45.2% vs. 16.3%, p<0.01), short sleep episodes (44.1% vs. 16.3%, p < 0.01), irregular bedtimes (29.0% vs. 12.8%, p < 0.01), and feeling tired upon awakening (15.1% vs. 3.5%, p < 0.01). Habitual napping and loud snoring were reported twice as often in shift/night than in day workers (p < 0.01). Nightmares, somnambulism, and unpleasant feeling in the legs were equality reported by both groups (p > 0.05). Few offshore workers had sought medical help for their sleep problems. A higher number of shift/night workers reported feelings of sadness compared with day workers (26.9% vs. 9.3%, p < 0.01). The findings of this study show that subjective reports of sleep-related problems are quite common among Brazilian offshore shift workers. Reliance on self-reported sleep problems and a cross-sectional design are the main limitations of our study.     

A Prospective Study of Seasonal Variation in Shift‐Work Tolerance

Seasonal effects on shift‐work tolerance were assessed using the Standardized Shiftwork Index and the 21‐item Hamilton Depression Scale. Participants (N=88) mainly worked a two‐day, two‐night, four‐off rotation with 12 h shifts changing at 06∶00 and 18∶00 h in Vancouver, Canada. At this latitude (～49° N), daylength varies seasonally from ～16 to ～8 h, and both daily commutes occur in the dark in mid‐winter and in sunlight in mid‐summer. Questionnaires were completed twice, near the summer and winter solstices (order counterbalanced). Outcome variables were mood, general psychological health, sleep quality, chronic fatigue, physical health, job satisfaction, and social and domestic disruption. Of these, general psychological health and mood were significantly worse in winter, while sleep was more disturbed in summer. In winter, 31% exceeded the cutoff for psychological distress, and >70% scored in the higher than normal range for depressive symptoms. In summer, the proportions dropped to 19% and 53%, respectively. Measures of physical health and psychosocial well‐being showed no seasonal effects. Relationships among explanatory and outcome variables, assessed by linear regression and canonical correlations, were also stable across season. Neuroticism was the strongest predictor of tolerance to shift work. Age was predictive only of sleep disturbance in both summer and winter. These results indicate that time of year can affect important outcome measures in shift‐work assessment and intervention studies. The high average scores on measures of psychological distress and depression in winter suggest that at northern latitudes, some shift schedules may increase the risk of seasonal‐type depression.     

Examining courses of sleep quality and sleepiness in full 2 weeks on/2 weeks off offshore day shift rotations

ABSTRACT

To better understand sleep quality and sleepiness problems offshore, we examined courses of sleep quality and sleepiness in full 2-weeks on/2-weeks off offshore day shift rotations by comparing pre-offshore (1 week), offshore (2 weeks) and post-offshore (1 week) work periods. A longitudinal observational study was conducted among N=42 offshore workers. Sleep quality was measured subjectively with two daily questions and objectively with actigraphy, measuring: time in bed (TIB), total sleep time (TST), sleep latency (SL) and sleep efficiency percentage (SE%). Sleepiness was measured twice a day (morning and evening) with the Karolinska Sleepiness Scale. Changes in sleep and sleepiness parameters during the pre/post and offshore work periods were investigated using (generalized) linear mixed models. In the pre-offshore work period, courses of SE% significantly decreased (p=.038). During offshore work periods, the courses of evening sleepiness scores significantly increased (p<.001) and significantly decreased during post-offshore work periods (p=.004). During offshore work periods, TIB (p<.001) and TST (p<.001) were significantly shorter, SE% was significantly higher (p=.002), perceived sleep quality was significantly lower (p<.001) and level of rest after wake was significantly worse (p<.001) than during the pre- and post-offshore work periods. Morning sleepiness was significantly higher during offshore work periods (p=.015) and evening sleepiness was significantly higher in the post-offshore work period (p=.005) compared to the other periods. No significant changes in SL were observed. Courses of sleep quality and sleepiness parameters significantly changed during full 2-weeks on/2-weeks off offshore day shift rotation periods. These changes should be considered in offshore fatigue risk management programmes.