Habitual Sleep, Social Jetlag, and Reaction Time in Youths With Delayed Sleep-Wake Phase Disorder. A Case-Control Study

The aim of this study was to explore habitual sleep, social jetlag, and day-to-day variations in sleep (measured as intra-individual standard deviation, ISD) in youths with delayed sleep-wake phase disorder (DSWPD), compared to healthy controls. We also aimed to investigate time of day effects in performance. The sample comprised 40 youths with DSWPD (70.0% female, mean age 20.7 ± 3.1 years) and 21 healthy controls (71.4% female, mean age 21.2 ± 2.2 years). Subjective and objective sleep were measured over 7 days on a habitual sleep schedule by sleep diary and actigraphy recordings. Performance was tested twice with a 12-h interval (22:00 in the evening and 10:00 the following morning) using a simple, 10-min sustained reaction time test (RTT). The results showed later sleep timing in the DSWPD group compared to the controls, but sleep duration, social jetlag, and ISD in sleep timing did not differ between the groups. Still, participants with DSWPD reported longer sleep onset latency (SOL) and poorer sleep efficiency (SE), sleep quality, and daytime functioning, as well as larger ISD in SOL, sleep duration, and SE. The groups had similar evening performances on the RTT, but the DSWPD group performed poorer (slower with more lapses) than the controls in the morning. The poor morning performance in the DSWPD group likely reflects the combined impact of sleep curtailment and circadian variations in performance (synchrony effect), and importantly illustrates the challenges individuals with DSWPD face when trying to adhere to early morning obligations.

Patient-reported depression treatment and future treatment preferences: an observational study in general practice

BACKGROUND

Depression is prevalent in general practice, but few studies have explored patient-reported depression care.

AIM

To investigate patient-reported treatment received for depression and future treatment preferences among adult patients visiting their GP, and to evaluate the associations with sex, age and educational level.

DESIGN AND SETTING

A cross-sectional survey was conducted in general practices in Norway from 2016 to 2017.

METHODS

Altogether, 2335 consecutive patients (response rate, 89.2%) in the GPs' waiting rooms answered a questionnaire about their received depression treatment and treatment preferences in case of future depression.

RESULTS

The study population (N = 2239) had a mean age of 48.6 ± 17.7 years (range 18-91), 60.1% were women. Of the 770 patients reporting to have received depression treatment, 39.1% were treated exclusively by their GP while 52.5% also were referred to a psychologist/psychiatrist. Older age was positively associated with medication and negatively associated with referrals to psychologist/psychiatrist. People with high education had lower odds for receiving medication (odds ratios [OR], 0.49; 95% confidence intervals [CI]: 0.30-0.80) compared to those with low education. If future depression, 81.6% of the respondents would discuss this with their GP, 60.9% would prefer talking therapy with their GP, 22.5% medication, and 52.9% referral to psychologist or psychiatrist.

CONCLUSION

One-third of the patients attending their GPs had consulted with them at some time concerning depression the case of future depression, most patients preferred talking therapy with the GP. This finding warrants increased research focus on the GP's role in depression care.

Pain complaints are associated with quick returns and insomnia among Norwegian nurses, but do not differ between shift workers and day only workers

PURPOSE

To determine whether common work schedule characteristics among Norwegian nurses were associated with subjective pain complaints.

METHODS

A cross-sectional study in a sample of 1585 nurses, part of the longitudinal questionnaire-based cohort project 'Survey of Shift work, Sleep and Health' (SUSSH). Pain from six regions were assessed: 'headache', 'neck/shoulder/upper back', 'upper extremities', 'lower back', 'lower extremities', and 'abdomen'. Logistic and negative binomial regression (adjusted for age, sex, percentage of full-time equivalent, marital status and children living at home) were conducted where work schedule, number of night shifts last year, number of quick returns (QR) last year (< 11 h between shifts) and insomnia were predictors of localized pain, widespread pain and number of pain sites.

RESULTS

Localized pain, widespread pain and number of pain sites were associated with insomnia (OR 2.06, 95% CI 1.66-2.55, OR 2.14, 95% CI 1.47-3.09, IRR 1.70, 95% CI 1.51-1.91, respectively). Work schedule and number of night shifts worked last year were not associated with any of the three pain measures. Number of QRs worked last year tended to be associated with number of pain sites.

CONCLUSION

The study did not support the hypothesis that non-daytime work schedules are associated with pain complaints. Neither was there support for the hypothesis linking number of night shifts, or the number of QRs, to pain complaints. Future studies should aim to determine the association between QRs and pain in more detail. Pain complaints were associated with insomnia.

Shift Work and Lifestyle Factors: A 6-Year Follow-Up Study Among Nurses

Objectives: To evaluate different work schedules, short rest time between shifts (quick returns), and night shift exposure for their possible adverse effects on different lifestyle factors in a 6-year follow-up study.

Methods: Data stemmed from “The Survey of Shiftwork, Sleep and Health,” a cohort study of Norwegian nurses started in 2008/9. The data analyzed in this sub-cohort of SUSSH were from 2008/9 to 2015 and consisted of 1,371 nurses. The lifestyle factors were: Exercise (≥1 h/week, <1 h/week), caffeine consumption (units/day), smoking (prevalence and cigarettes/day), and alcohol consumption (AUDIT-C score). We divided the nurses into four groups: (1) day workers, (2) night workers, (3) nurses who changed toward, and (4) nurses who changed away from a schedule containing night shifts. Furthermore, average number of yearly night shifts (NN), and average number of quick returns (QR) were calculated. Paired t-tests, McNemar tests, and logistic regression analyses were used in the analyses.

Results: We found a significant increase in caffeine consumption across all work schedule groups and a decline in smoking prevalence for day workers and night workers at follow-up. Analyses did not show any significant differences between groups when analyzing (1) different work schedules, (2) different exposures to QR, (3) different exposures to NN on the respective lifestyle factor trajectories.

Conclusion: We found no significant differences between the different work schedule groups or concerning different exposures to QR or NN when evaluating these lifestyle factor trajectories. This challenges the notion that shift work has an adverse impact on lifestyle factors.

Insomnia symptom trajectories among adult survivors of childhood sexual abuse: A longitudinal study

BACKGROUND

Childhood sexual abuse (CSA) is associated with sleep disturbances in adulthood. However, longitudinal studies have yet to identify among CSA-survivors subgroups distinguished by the trajectory of their insomnia severity, or predictors of subgroup membership.

OBJECTIVE

The objective of this study was to examine longitudinal insomnia symptom trajectories, as well as predictors and correlates of the identified trajectories, over a 4 year study period in a sample of adult, mainly female CSA-survivors.

PARTICIPANTS AND SETTING

The sample comprised 533 adult survivors of CSA (94.9% women, mean age 39.2 years, mean age of abuse onset 6.5 years), recruited from support centers for sexual abuse survivors in Norway.

METHODS

Latent class growth analyses were used to identify insomnia symptom trajectories.

RESULTS

Three distinct trajectories of insomnia symptoms were identified; one characterized by high insomnia symptom scores minimally decreasing over the study period ('high and decreasing', 30.6%), one characterized by stable intermediate insomnia symptom scores ('intermediate and stable', 41.5%), and one characterized by stable low insomnia symptom scores ('low and stable', 27.9%). Predictors of belonging to the high and decreasing trajectory (using the low and stable trajectory as a reference), was lower age of abuse onset (expotentiated coefficient (EC): 0.93, p = 0.026), abuse involving penetration (EC: 2.36, p = 0.005), threats (EC: 3.06, p < 0.001) or physical violence (EC: 3.29 p < 0.001), a higher score on a composite variable comprising multiple other abuse and perpetrator aspects (EC: 2.55, p < 0.001), as well as scoring above a clinical cut-off on a measure of posttraumatic stress symptoms (EC: 12.17, p < 0.001). Those belonging to the high and decreasing trajectory also reported lower levels of perceived social support and higher levels of subjectively experienced relational difficulties compared to those belonging to the two other trajectories.

CONCLUSIONS

We conclude that different longitudinal insomnia trajectories exist among adult CSA survivors. The overall results, as well as the significant predictors, are discussed alongside their potential clinical implications.

The when and how of the gynaecological examination: a survey among Norwegian general practitioners

Introduction: Little is known about the indications general practitioners (GPs) perceive as relevant for performing gynaecological examinations (GEs), how GPs master the GE and associated procedures, and how they handle the sensitive nature of GEs. Methods: In 2015, 70 medical students at the University of Bergen distributed a questionnaire to all 175 GPs in the practices they visited. The questions covered practical routines related to GEs, insertion of intrauterine device, frequency of GEs in different clinical settings and use of assisting personnel. Statistical analyses included chi-square tests and multiple logistic regressions adjusting for age, gender, specialization and localization. Results: Ninety male and 61 female GPs (87% of invited GPs) responded to the questionnaire. A minority (8%) usually had other staff present during GEs. Compared with female colleagues, male GPs performed bimanual palpation significantly less often in connection with routine Pap smear (AOR 0.3 (95% CI 0.1-0.6)). Twenty-eight percent of the GPs stated that they often/always omitted the GE if the patient was anxious about GE and 35% when the patient asked for referral to a gynaecologist. Omission was more frequent among male GPs. When the GP decided to refer to a gynaecologist based on the patient's symptoms, more male than female GPs omitted GE (AOR 2.5 (95% CI 1.1-5.4)). Conclusion: Male gender of the GP may be associated with barriers to medical evaluation of pelvic symptoms in women, potentially leading to substandard care. Possibly, however, male GPs' reluctance to perform the GE may also limit unnecessary bimanual palpation in asymptomatic women.

Insomnia as a Partial Mediator of the Relationship Between Personality and Future Symptoms of Anxiety and Depression Among Nurses

Background: This study investigates insomnia as a partial mediator in the relationship between personality and symptoms of anxiety and depression.

Methods: The study is based on partly longitudinal data from the ongoing cohort study “Survey of Shift work, Sleep, and Health” (SUSSH) among Norwegian nurses, a survey examining the work situation and health status of Norwegian nurses measured with annual questionnaires. The present study uses data collected in 2012 (Wave 4), 2013 (Wave 5), and 2014 (Wave 6). The final sample at Wave 6 consisted of 2002 participants, of which 91% were females. The questionnaires included items measuring, among others, demographic variables, work time schedule, insomnia (Bergen Insomnia Scale), personality (Mini-IPIP) and anxiety and depression (Hospital Anxiety and Depression Scale).

Results: Extraversion and conscientiousness had no significant direct or indirect association with insomnia, anxiety or depression. Neuroticism and insomnia had direct associations to future symptoms of anxiety and depression. Insomnia was also a significant partial mediator of the relationship between both neuroticism and anxiety, and neuroticism and depression, meaning that neuroticism had an indirect relation to symptoms of anxiety and depression through insomnia. When adjusting for previous symptoms of anxiety and depression at Wave 5, insomnia was no longer a significant mediator between neuroticism and anxiety, and only marginally mediated the relationship between neuroticism and depression.

Conclusion: The results showed that insomnia may act as a mediator between neuroticism and symptoms of anxiety and depression, but the indirect relationship between neuroticism and anxiety and depression through insomnia is considerably weaker than the direct association. Hence, the mediating effect of insomnia should be interpreted with caution. The sample mainly consisted of female nurses, and the generalizability of the findings to male dominated occupations is limited. Findings from the present study highlight the importance of an integrated approach and strengthen the understanding of how personality and psychopathology are connected.

Working hour characteristics and schedules among nurses in three Nordic countries - a comparative study using payroll data

Background

Organisation of working hour schedules in the Northern European countries are rather similar. EU countries are obliged to adopt national legislation regarding duration of weekly working hours and rest periods. Yet, working hour characteristics and schedules are likely to differ with respect to starting times and duration depending e.g. on culture and tradition. Yet, very little is known about potential differences between shifts and schedules across countries among nursing personel. This knowledge is relevant, since the potential differences in working hour characteristics may influence and possibly explain some of the differences observed in studies of health and safety.The aim of the study was to compare characteristics of working hours and work schedules among nursing personel in three Nordic countries: Denmark, Finland and Norway.

Methods

The study populations included nursing personnel holding a ≥ 50% position at public hospitals in Denmark (n = 63,678), Finland (n = 18,257) or Norway (n = 1538) in 2013. Objective payroll based registry data with information on daily starting and ending times were used to compare working hour characteristics e.g. starting time, duration of shift, and quick returns (< 11 h between two shifts), as well as work schedules e.g. permanent or 3-shift work between the three countries.

Results

Night shifts generally started earlier and lasted longer in Finland (10-11 h starting at 20:00-22:59) than in Norway (10 h starting at 21:00-21:59) and in Denmark (8 h starting at 23:00-23:59). Very long shifts (≥12 h) were more common in Denmark (12%) compared to Finland (8%) and Norway (3%). More employees had many (> 13/year) quick returns in Norway (64%) and Finland (47%) compared to Denmark (16%). The frequency of 3-shift rotation workers was highest in Norway (41%) and lower in Denmark (22%) and Finland (22%). There were few differences across the countries in terms of early morning shifts and (very) long weekly working hours.

Conclusion

Despite similar distribution of operational hours among nurses in the three countries, there were differences in working hour characteristics and the use of different types of work schedules. The observed differences may affect health and safety.

The Short-Term Efficacy of an Unguided Internet-Based Cognitive-Behavioral Therapy for Insomnia: A Randomized Controlled Trial With a Six-Month Nonrandomized Follow-Up

OBJECTIVE

Insomnia is a major health problem, and the need for effective and accessible treatment is urgent. The aim of the current study was to evaluate the short-term efficacy of an unguided Internet-based cognitive-behavioral treatment program for insomnia (CBTi), called SHUTi (Sleep Healthy Using the Internet).

METHODS

This study used a parallel arm randomized controlled trial in Norway. Participants were randomly allocated to the SHUTi condition or a Web-based patient education condition. Both groups were assessed before and after the nine-week intervention period (online sleep diaries and questionnaires). The SHUTi participants were reassessed in a six-month nonrandomized follow-up. Primary outcome measures were the Insomnia Severity Index (ISI) and the Bergen Insomnia Scale (BIS).

RESULTS

A total of 181 participants were included in the study; SHUTi condition (n = 95), patient education condition (n = 86). Intention-to-treat mixed-model repeated-measures analysis revealed that the SHUTi group had better short-term outcomes compared with the patient education group on most sleep measures. The SHUTi group showed a significant decrease on the primary outcomes, the ISI (d_between = -1.77, 95% CI = -2.23, -1.31) and the BIS (d_between = -1.00, 95% CI = -1.32, -.68). Improvements were maintained among the completing SHUTi participants at the six-month nonrandomized follow-up. However, dropout attrition was high.

CONCLUSION

Unguided Internet-based CBTi produced significant short-term improvements in sleep in patients with chronic insomnia. This highlights the benefits of making Internet-delivered CBTi programs available as a standard first-line treatment option in public health services. Nevertheless, the rate of dropout attrition (participants not completing post-assessment) in this trial limits the generalizability of the findings.

Correlation between Excessive Daytime Sleepiness (EDS) and self-reported and objective nasal characteristics

BACKGROUND

The aim of the present study was to explore the relationship between excessive daytime sleepiness (EDS), Peak Nasal Inspiratory Flow (PNIF), and patient reported symptoms from the nose.

METHOLOGY

Six hundred and fifty one consecutive patients referred to a hospital on suspicion of sleep related breathing disorder (SRBD) were included in the study. Daytime sleepiness was assessed by Epworth Sleepiness Scale (EpSS). Nasal airflow was measured with Peak Nasal Inspiratory Flow (PNIF). Symptoms of sino-nasal dysfunction and diseases were graded on Visual Analogue Scales (VAS).

RESULTS

EpSS score was not correlated with nasal flow as measured by PNIF or nasal obstruction - VAS scores. There were significant associations between daytime sleepiness and patient-reported VAS-scores on nasal discharge, headache, coughing, general health and to some extent sneezing when age, gender, BMI and reported co-morbidity levels were adjusted for.

CONCLUSION

A clinical implication of this is that patients with EDS may be evaluated and treated for sino-nasal disease, while medical and surgical measures to open the nose per se may not be effective therapeutic options. A scientific implication is that the relationship between SRBD and sino-nasal disease should be further investigated.

Sleep problems, behavioural problems and respiratory health in children born extremely preterm: a parental questionnaire study

OBJECTIVE

To explore whether children born extremely preterm (EPT) with different types of sleep problems had more behavioural and respiratory health problems than EPT children without sleep problems.

DESIGN

Prospective, nationwide, questionnaire-based study. At 11 years of age, parents reported on four current sleep problems: difficulty falling asleep or frequent awakenings, snoring, daytime sleepiness and not recommended sleep duration (<9 hours). Behavioural problems were assessed by parents and teachers with the Strengths and Difficulties Questionnaire (SDQ). Parents assessed respiratory symptoms with the International Study of Asthma and Allergies in Childhood questionnaire and described use of asthma medication.

SETTING

Norway.

PATIENTS

EPT children.

MAIN OUTCOME MEASURES

Specified sleep problems, behavioural problems and respiratory health.

RESULTS

Data were obtained from 216 of 372 (58 %) of eligible children. All four specified sleep problems were associated with significantly higher parent-reported SDQ total-score (OR 1.1 for all), and except for not recommended sleep duration, also with higher teacher-reported SDQ total-score (OR 1.1 for all). Daytime sleepiness was strongly associated with wheezing last 12 months (OR 3.4), disturbed sleep due to wheezing (OR 3.9), wheeze during or after exercise (OR 2.9), use of inhaled corticosteroids or oral leukotriene modifiers (OR 3.4) and use of bronchodilators (OR 3.9). Snoring was associated with wheezing during or after exercise (OR 2.8) and current asthma (OR 4.2).

CONCLUSION

EPT children with different types of sleep problems had more behavioural and respiratory health problems than EPT children without sleep problems.

Causes and Management of Sleepiness Among Pilots in a Norwegian and an Austrian Air Ambulance Service-A Comparative Study

OBJECTIVE

We compared subjectively reported sleepiness and fatigue as well as causes and management strategies for combating sleepiness among pilots working in 2 different helicopter emergency medical services operating with different shift systems.

METHODS

Pilots from the Norwegian Air Ambulance (NAA) and Christophorus Flugrettungsverein (CFV) in Austria participated. NAA performs flight missions 24/7, whereas at the time of the study the participating CFV bases did not fly after sunset. The pilots are on duty for 1 week in both services. NAA and CFV used an identical research protocol, including questionnaires about sleep, sleepiness (Epworth Sleepiness Scale and Karolinska Sleepiness Scale), coping strategies, and work-related causes of fatigue.

RESULTS

CFV pilots kept busy, whereas NAA pilots slept and did physical exercise as strategies to prevent sleepiness. The majority in both groups used napping and coffee consumption as strategies. CFV pilots reported more frequently than NAA pilots that administrative duties and environmental factors were reasons preventing napping.

CONCLUSION

Some differences existed between the 2 pilot groups regarding strategies for managing sleepiness and causes that prevented pilots from napping. Pilots in both groups were healthy, physically active, and had normal Epworth Sleepiness Scale and Karolinska Sleepiness Scale scores.

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.

Migraine, tension-type headache and medication-overuse headache in a large population of shift working nurses: a cross-sectional study in Norway

OBJECTIVES

To investigate associations between different types of headaches and shift work.

DESIGN, PARTICIPANTS AND OUTCOME MEASURES

Nurses with different work schedules (day work, two-shift rotation, night work, three-shift rotation) participated in a cohort study with annual surveys that started in 2008/2009. In 2014 (wave 6), a comprehensive headache instrument was included in the survey, in which 1585 nurses participated. Headaches were assessed according to the International Classification of Headache Disorders IIIb. Frequent headache (≥1 day per month), migraine, tension-type headache, chronic headache (headache >14 days per month) and medication-overuse headache (chronic headache + acute headache medication ≥10 days last month) comprised the dependent variables. Adjusted (for sex, age, percentage of full-time equivalent, marital status, children living at home) logistic regression analyses were conducted with work schedule, number of night shifts worked last year, number of quick returns (<11 hours in-between shifts) last year, shift work disorder and insomnia disorder as predictors.

RESULTS

Frequent headache, migraine and chronic headache were associated with shift work disorder (OR 2.04, 95% CI 1.62 to 2.59; 1.60, 1.21 to 2.12; 2.45, 1.25 to 4.80, respectively) and insomnia disorder (OR 1.79, 95% CI 1.43 to 2.23; 1.55, 1.18 to 2.02; 3.03, 1.54 to 5.95, respectively), but not with work schedule, number of night shifts or number of quick returns. Tension-type headache was only associated with >20 night shifts last year (OR 1.41, 95% CI 1.07 to 1.86). Medication-overuse headache was only associated with insomnia disorder (OR 7.62, 95% CI 2.48 to 23.41).

CONCLUSIONS

We did not find any association between different types of headaches and work schedule. However, tension-type headache was associated with high number of night shifts. Nurses with sleep disorders (insomnia disorder and shift work disorder) reported higher prevalence of frequent headaches, migraine, chronic headache and medication-overuse headache (only insomnia) compared with nurses not having insomnia disorder and shift work disorder, respectively.

Sleep duration mediates abdominal and lower-extremity pain after night work in nurses

OBJECTIVES

The aim of this study was to investigate the association between different working shifts (i.e. morning, evening, night shifts) and headache, musculoskeletal and abdominal pain, and the extent to which reduced sleep duration could account for these associations.

METHODS

Nurses (N = 679, 649 female, aged 22-53 years) were followed up for a period of 28 consecutive days, responding to a diary about sleep, shift type and pain complaints (measured on a Likert-type scale ranging from 0 to 3). Generalised structural equation modelling mediation analysis (GSEM) was performed to test whether shift type was associated with higher incidence or higher intensity of pain (headache, pain in neck/shoulders/upper back, upper extremity, low back, lower extremity and abdominal pain), and if this effect was mediated by sleep duration (continuous variable), after controlling for age, work and lifestyle factors.

RESULTS

Pain scores in lower extremities were decreased following night shifts in general. However, when night shifts were followed by short sleep duration, the risk of pain in the lower extremities and abdominal pain were increased. Headache and pain in the upper extremity were increased after night shifts, but were not associated with sleep duration. Pain in the neck/shoulder/upper back and lower back was not related to shift work.

CONCLUSIONS

Among nurses in a three-shift rotating schedule, night shifts increased the risk of pain in several regions, but only pain in the lower extremities and abdomen was related to reduced sleep duration.

Long working hours are inversely related to sick leave in the following 3 months: a 4-year registry study

PURPOSE

The aim of this study was to investigate the effects of long working hours (≥ 12 h shifts) on sick leave using objective records of shift work exposure and of sick leave.

METHODS

A total of 1538 nurses (mean age 42.5, SD 12.0; response rate 42%) participated. Payroll and archival sick leave data over a 4-year period were retrieved from employers' records and aggregated over every third calendar month. A multilevel negative binomial model was used to investigate the effects of exposure to long working hours, on subsequent sick leave rates the following 3 months. Covariates included prior sick leave, number of shifts worked, night and evening shifts, personality, and demographic characteristics.

RESULTS

Exposure to long working hours was associated with fewer sick leave days in the subsequent 3 months [adjusted model, incidence rate ratio (IRR) = 0.946, 95% CI 0.919-0.973, p < 0.001]. The interaction long working hours by a number of work days showed that sick leave days the subsequent 3 months was higher by long shifts when number of shifts was high compared to when number of shifts was low [adjusted model, IRR 1.002, 95% CI 1.000-1.004, p < 0.05].

DISCUSSION

Long working hours was associated with fewer sick leave days. The restorative effects of extra days off with long working hours are discussed as possible explanations to this relationship.

Workaholism and negative work-related incidents among nurses

The present study comprised 1,781 nurses who participated in an investigation about working conditions, sleep, and health. They answered a questionnaire about age, sex, marital status, children living at home, work hours per week, number of night shifts last year, and total sleep duration and that also included a validated instrument assessing workaholism. In addition, they were asked to report on eight items concerning negative work-related incidents (dozed off at work, dozed while driving, harmed or nearly harmed self, harmed or nearly harmed patients/others, and harmed or nearly harmed equipment). Logistic regression analyses identified several predictors of these specific incidents: Low age (dozed at work, harmed and nearly harmed self, harmed and nearly harmed equipment), male sex (harmed and nearly harmed self, nearly harmed equipment), not living with children (harmed patients/others), low percentage of full-time equivalent (nearly harmed self and harmed patients/others), number of night shifts last year (dozed off at work and while driving, nearly harmed patients/others) and sleep duration (inversely related to dozed off at work and while driving, nearly harmed self). However, the most consistent predictor of negative work-related incidents was workaholism which was positively and significantly associated with all the eight incidents.

Factors associated with self-rated health in primary care

BACKGROUND

Self-rated health (SRH) measures one's current general health and is a widely used health indicator. Sleep problems, somatic health complaints, and unmet needs in interpersonal relationships are suspected to influence SRH, but studies in primary health care settings are sparse.

OBJECTIVE

To examine the associations between patients' self-rated health and their sleep problems, somatic health complaints, and unmet needs in interpersonal relationships.

DESIGN

We collected data via questionnaires for this cross-sectional study from general practice.

SETTING

Primary health care in Norway.

SUBJECTS

1302 consecutive patients participated.

MAIN OUTCOME MEASURES

The questionnaire included a single question about SRH, the Bergen Insomnia Scale (BIS), five questions on somatic health complaints, and three questions from the Basic Psychological Needs Scale (BPNS) pertaining to the relationships domain. We analyzed our data using ordinal logistic regression models.

RESULTS

Our response rate was 74%. The prevalence of fair/poor SRH was 26%, with no gender differences. We revealed a significant association between increasing age and reduced SRH. The study showed that sleep problems and somatic health complaints were strongly associated with SRH, and unmet needs in relationships were also significantly and independently associated with reduced SRH in a full model analysis.

CONCLUSION

Sleep problems, somatic health complaints, and unmet needs in interpersonal relationships were all associated with reduced SRH. These factors are all modifiable and could be managed both within and outside a primary care setting in order to improve SRH. Key Points There was a high prevalence of reduced SRH in clinical general practice Sleep problems, somatic health complaints, and unmet needs in interpersonal relationships were all associated with reduced SRH These predictors are all modifiable with a potential to improve SRH.