Associations between obesity, a composite risk score for probable long COVID, and sleep problems in SARS-CoV-2 vaccinated individuals.

BACKGROUND: Preliminary data suggests that obesity might hasten the decline in mRNA vaccine-induced immunity against SARS-CoV-2. However, whether this renders individuals with obesity more susceptible to long COVID symptoms post-vaccination remains uncertain. Given sleep's critical role in immunity, exploring the associations between obesity, probable long COVID symptoms, and sleep disturbances is essential. METHODS: We analyzed data from a survey of 5919 adults aged 18 to 89, all of whom received two SARS-CoV-2 mRNA vaccinations. Participants were categorized into normal weight, overweight, and obesity groups based on ethnicity-specific BMI cutoffs. The probability of long COVID was evaluated using the Post-Acute Sequelae of SARS-CoV-2 (PASC) score, as our survey did not permit confirmation of acute SARS-CoV-2 infection through methods such as antibody testing. Additionally, sleep patterns were assessed through questionnaires. RESULTS: Participants with obesity exhibited a significantly higher adjusted odds ratio (OR) of having a PASC score of 12 or higher, indicative of probable long COVID in our study, compared to those with normal weight (OR: 1.55, 95% CI: 1.05, 2.28). No significant difference was observed for overweight individuals (OR: 0.92 [95% CI: 0.63, 1.33]). Both obesity and probable long COVID were associated with increased odds of experiencing a heightened sleep burden, such as the presence of obstructive sleep apnea or insomnia (P < 0.001). However, no significant interaction between BMI and probable long COVID status was found. CONCLUSIONS: Even post-vaccination, individuals with obesity may encounter a heightened risk of experiencing prolonged COVID-19 symptoms. However, confirming our observations necessitates comprehensive studies incorporating rigorous COVID infection testing, such as antibody assays - unavailable in our anonymous survey. Additionally, it is noteworthy that the correlation between probable long COVID and sleep disturbances appears to be independent of BMI.

Nightmare frequency is a risk factor for suicidal ideation during the COVID-19 pandemic.

The association between nightmare frequency (NMF) and suicidal ideation (SI) is well known, yet the impact of the COVID-19 pandemic on this relation is inconsistent. This study aimed to investigate changes in NMF, SI, and their association during the COVID-19 pandemic. Data were collected in 16 countries using a harmonised questionnaire. The sample included 9328 individuals (4848 women; age M[SD] = 46.85 [17.75] years), and 17.60% reported previous COVID-19. Overall, SI was significantly 2% lower during the pandemic vs. before, and this was consistent across genders and ages. Most countries/regions demonstrated decreases in SI during this pandemic, with Austria (-9.57%), Sweden (-6.18%), and Bulgaria (-5.14%) exhibiting significant declines in SI, but Italy (1.45%) and Portugal (2.45%) demonstrated non-significant increases. Suicidal ideation was more common in participants with long-COVID (21.10%) vs. short-COVID (12.40%), though SI did not vary by COVID-19 history. Nightmare frequency increased by 4.50% during the pandemic and was significantly higher in those with previous COVID-19 (14.50% vs. 10.70%), during infection (23.00% vs. 8.10%), and in those with long-COVID (18.00% vs. 8.50%). The relation between NMF and SI was not significantly stronger during the pandemic than prior (rs = 0.18 vs. 0.14; z = 2.80). Frequent nightmares during the pandemic increased the likelihood of reporting SI (OR = 1.57, 95% CI 1.20-2.05), while frequent dream recall during the pandemic served a protective effect (OR = 0.74, 95% CI 0.59-0.94). These findings have important implications for identifying those at risk of suicide and may offer a potential pathway for suicide prevention.

Sleep symptoms are essential features of long-COVID - Comparing healthy controls with COVID-19 cases of different severity in the international COVID sleep study (ICOSS-II).

Many people report suffering from post-acute sequelae of COVID-19 or "long-COVID", but there are still open questions on what actually constitutes long-COVID and how prevalent it is. The current definition of post-acute sequelae of COVID-19 is based on voting using the Delphi-method by the WHO post-COVID-19 working group. It emphasizes long-lasting fatigue, shortness of breath and cognitive dysfunction as the core symptoms of post-acute sequelae of COVID-19. In this international survey study consisting of 13,628 subjects aged 18-99 years from 16 countries of Asia, Europe, North America and South America (May-Dec 2021), we show that post-acute sequelae of COVID-19 symptoms were more prevalent amongst the more severe COVID-19 cases, i.e. those requiring hospitalisation for COVID-19. We also found that long-lasting sleep symptoms are at the core of post-acute sequelae of COVID-19 and associate with the COVID-19 severity when COVID-19 cases are compared with COVID-negative cases. Specifically, fatigue (61.3%), insomnia symptoms (49.6%) and excessive daytime sleepiness (35.8%) were highly prevalent amongst respondents reporting long-lasting symptoms after hospitalisation for COVID-19. Understanding the importance of sleep-related symptoms in post-acute sequelae of COVID-19 has a clinical relevance when diagnosing and treating long-COVID.

Associations between changes in habitual sleep duration and lower self-rated health among COVID-19 survivors: findings from a survey across 16 countries/regions.

BACKGROUND: Self-rated health (SRH) is widely recognized as a clinically significant predictor of subsequent mortality risk. Although COVID-19 may impair SRH, this relationship has not been extensively examined. The present study aimed to examine the correlation between habitual sleep duration, changes in sleep duration after infection, and SRH in subjects who have experienced SARS-CoV-2 infection. METHODS: Participants from 16 countries participated in the International COVID Sleep Study-II (ICOSS-II) online survey in 2021. A total of 10,794 of these participants were included in the analysis, including 1,509 COVID-19 individuals (who reported that they had tested positive for COVID-19). SRH was evaluated using a 0-100 linear visual analog scale. Habitual sleep durations of < 6 h and > 9 h were defined as short and long habitual sleep duration, respectively. Changes in habitual sleep duration after infection of ≤ -2 h and ≥ 1 h were defined as decreased or increased, respectively. RESULTS: Participants with COVID-19 had lower SRH scores than non-infected participants, and those with more severe COVID-19 had a tendency towards even lower SRH scores. In a multivariate regression analysis of participants who had experienced COVID-19, both decreased and increased habitual sleep duration after infection were significantly associated with lower SRH after controlling for sleep quality (ß = -0.056 and -0.058, respectively, both p < 0.05); however, associations between current short or long habitual sleep duration and SRH were negligible. Multinomial logistic regression analysis showed that decreased habitual sleep duration was significantly related to increased fatigue (odds ratio [OR] = 1.824, p < 0.01), shortness of breath (OR = 1.725, p < 0.05), diarrhea/nausea/vomiting (OR = 2.636, p < 0.01), and hallucinations (OR = 5.091, p < 0.05), while increased habitual sleep duration was significantly related to increased fatigue (OR = 1.900, p < 0.01). CONCLUSIONS: Changes in habitual sleep duration following SARS-CoV-2 infection were associated with lower SRH. Decreased or increased habitual sleep duration might have a bidirectional relation with post-COVID-19 symptoms. Further research is needed to better understand the mechanisms underlying these relationships for in order to improve SRH in individuals with COVID-19.

Which outcomes should be measured in hand eczema trials? Results from patient interviews and an expert survey.

BACKGROUND: Hand eczema (HE) is a common skin disease characterized by itch, pain and visible skin changes such as fissures, erythema and vesicles. It is not yet clear which outcome domains are most important for patients. The Hand Eczema Core Outcome Set (HECOS) initiative is developing a consented set of core domains and suitable measurement instruments for the future application in all HE trials. This includes an online Delphi survey about core domains, which requires a 'Long List' of all domains that might be important to measure. OBJECTIVES: To compile a 'Long List' of candidate outcome domains for therapeutic HE trials with suggestions from patients and experts. METHODS: First, 60 patients with chronic HE were interviewed at seven study sites in Croatia, Denmark, Germany, the Netherlands and Spain. Patients were asked about domains that were important from their perspectives. Second, 185 HE experts were invited by email to complete an online survey. With an open question, they were asked to suggest up to six domains. RESULTS: Suggestions were provided by 58 patients and 82 experts. Most patients and experts suggested to measure the domains 'signs', 'symptoms' and 'HE-related quality of life'. Specifically, >25% of patients said that less itch, pain or fissures indicated a successful treatment. Among experts, >25% suggested 'itch' and 'ability to work' as core sub-domains. Further outcomes from the domains 'HE control over time', 'patient-reported treatment experience' and 'skin barrier function' were mentioned. CONCLUSION: 'Itch' was rated high among patients with HE and professional HE experts. While patients emphasized fissures as important, experts underlined the ability to work. This investigation allowed us to define a 'Long List' of 7 candidate outcome domains with 58 sub-domains. From this list, a panel of stakeholders will select core domains during an online Delphi survey.

Factors related to skin health in hairdressing apprentices from two Croatian regions.

BACKGROUND: Hairdressing apprentices are at high risk for developing occupational contact dermatitis. OBJECTIVES: The objective of this study was to analyse whether there are differences in skin health, skin protection and health-related quality of life between apprentices from two Croatian regions (Zagreb and Dalmatia). MATERIALS AND METHODS: Final-year hairdressing apprentices from Zagreb (n = 101) and Dalmatia (n = 77) were enrolled in the study. Clinical examination of hands was performed by use of the Osnabrück Hand Eczema Severity Index. Transepidermal water loss (TEWL) was measured on forearm and hand. A history of self-reported skin symptoms, work-related exposure to skin hazards and health-related quality of life were assessed with validated questionnaires. RESULTS: Apprentices from Zagreb reported having been engaged in practical work more days per month than Dalmatian apprentices (median 12 days vs 8 days, respectively, P < 0.001), and washing their hands >20 times per day more frequently (28% vs 10%, respectively, P = 0.004), and consequently more frequently having dry hands (37% vs 16%, respectively, P = 0.002), and significantly higher TEWL values on the hand and forearm, which was confirmed by the results obtained with multiple linear regression models. CONCLUSIONS: A higher extent of exposure to skin hazards was related to poorer skin barrier function, which confirms the need for improvement of appropriate safety practices in hairdressing schools.

Morningness-eveningness and daytime functioning in university students: the mediating role of sleep characteristics.

The aim of this study was to explore the mediating role of sleep characteristics in the relationship between morningness-eveningness and three different aspects of daytime functioning: daytime sleepiness, depressive mood and substance use in university students. A multiple mediator model was proposed with sleep debt, poor sleep quality and bedtime delay at weekends as parallel mediators in these relationships. We analysed the data of 1052 university students aged 18-25 years who completed a modified version of the School Sleep Habits Survey, which included questions on sleep and the Composite Scale of Morningness, Sleepiness Scale, Depressive Mood Scale and Substance Use Scale. Students with more pronounced eveningness reported greater daytime sleepiness, greater depressive mood and more frequent substance use, as well as greater sleep debt, poorer sleep quality and greater bedtime delay at weekends. Mediation analyses indicated that morningness-eveningness affected daytime sleepiness and substance use both directly and indirectly through all proposed sleep-related mediators. However, the effect of morningness-eveningness on depressive mood was entirely indirect and was accounted for more by poor sleep than by sleep debt or bedtime irregularity. In conclusion, there are multiple possible mechanisms through which morningness-eveningness affects daytime functioning in university students, and sleep characteristics are a significant mechanism. Sleep debt, poor sleep quality and bedtime irregularity can, to a significant extent, explain the feeling of daytime sleepiness and greater substance use in students with eveningness preferences. However, more depressed mood in the evening-orientated students is primarily a consequence of their poor sleep quality.

The Relationship Between Work-Related Stress and Depression: A Scoping Review.

Objectives: Work-related stress is highly prevalent. Recent systematic reviews concluded on a significant association between common work-related stress measures and depression. Our scoping review aims to explore whether work-related psychosocial stress is generally associated with depression or depressiveness, the extent and methodology of the primary research undertaken on this topic and to elucidate inconsistencies or gaps in knowledge. Methods: We searched for literature in Pubmed, PsycInfo and Web of Science including full reports in seven languages published between 1999 and 2022 and applied the PRISMA statement for scoping reviews criteria. Results: Of 463 primarily identified articles, 125 were retained after abstract and full-text screening. The majority report significant associations between work-related stress and depression. Cross-sectional studies are most prevalent. Sufficient evidence exists only for job strain and effort-reward imbalance. Most studies are from Asia, North America and Europe. The health sector is the most studied. Several research gaps such as the lack of interventional studies were identified. Conclusion: The consistency of most studies on the significant association between work-related stress and depression is remarkable. More studies are needed to improve evidence and to close research gaps.

Habitual short sleepers with pre-existing medical conditions are at higher risk of Long COVID.

STUDY OBJECTIVES: Preliminary evidence suggests that the risk of Long COVID is higher among people with pre-existing medical conditions. Based on its proven adjuvant role in immunity, habitual sleep duration may alter the risk of developing Long COVID. The objective of this study was to determine whether the odds of Long COVID are higher among those with pre-existing medical conditions, and whether the strength of this association varies by habitual sleep duration. METHODS: Using data from 13,461 respondents from 16 countries who participated in the 2021 survey-based International COVID Sleep Study II (ICOSS II), we studied the associations between habitual sleep duration, pre-existing medical conditions, and Long COVID. RESULTS: Of 2,508 individuals who had COVID-19, 61% reported at least 1 Long COVID symptom. Multivariable logistic regression analysis showed that the risk of having Long COVID was 1.8-fold higher for average-length sleepers (6-9 h/night) with pre-existing medical conditions compared with those without pre-existing medical conditions (adjusted odds ratio [aOR] 1.84 [1.18-2.90]; P = .008). The risk of Long COVID was 3-fold higher for short sleepers with pre-existing medical conditions (aOR 2.95 [1.04-8.4]; P = .043) and not significantly higher for long sleepers with pre-existing conditions (aOR 2.11 [0.93-4.77]; P = .073) compared with average-length sleepers without pre-existing conditions. CONCLUSIONS: Habitual short nighttime sleep duration exacerbated the risk of Long COVID in individuals with pre-existing conditions. Restoring nighttime sleep to average duration represents a potentially modifiable behavioral factor to lower the odds of Long COVID for at-risk patients. CITATION: Berezin L, Waseem R, Merikanto I, et al. Habitual short sleepers with pre-existing medical conditions are at higher risk of long COVID. J Clin Sleep Med. 2024;20(1):111-119.

Estimation bias and agreement limits between two common self-report methods of habitual sleep duration in epidemiological surveys.

Accurate measurement of habitual sleep duration (HSD) is crucial for understanding the relationship between sleep and health. This study aimed to assess the bias and agreement limits between two commonly used short HSD self-report methods, considering sleep quality (SQ) and social jetlag (SJL) as potential predictors of bias. Data from 10,268 participants in the International COVID Sleep Study-II (ICOSS-II) were used. Method-Self and Method-MCTQ were compared. Method-Self involved a single question about average nightly sleep duration (HSDself), while Method-MCTQ estimated HSD from reported sleep times on workdays (HSDMCTQwork) and free days (HSDMCTQfree). Sleep quality was evaluated using a Likert scale and the Insomnia Severity Index (ISI) to explore its influence on estimation bias. HSDself was on average 42.41 ± 67.42 min lower than HSDMCTQweek, with an agreement range within ± 133 min. The bias and agreement range between methods increased with poorer SQ. HSDMCTQwork showed less bias and better agreement with HSDself compared to HSDMCTQfree. Sleep duration irregularity was - 43.35 ± 78.26 min on average. Subjective sleep quality predicted a significant proportion of variance in HSDself and estimation bias. The two methods showed very poor agreement and a significant systematic bias, both worsening with poorer SQ. Method-MCTQ considered sleep intervals without adjusting for SQ issues such as wakefulness after sleep onset but accounted for sleep irregularity and sleeping in on free days, while Method-Self reflected respondents' interpretation of their sleep, focusing on their sleep on workdays. Including an SQ-related question in surveys may help bidirectionally adjust the possible bias and enhance the accuracy of sleep-health studies.

Psychological Stress and Hand Eczema in Physicians and Dentists: A Comparison Based on Surgical Work.

BACKGROUND: This research looks at the connection between psychological stress and the prevalence of hand eczema (HE) among physicians and dentists (surgeons, non-surgeons). METHODS: This cross-sectional field study involved 185 participants: physicians (surgeons, non-surgeons), dentists (surgeons, non-surgeons) and controls. Hand lesions were examined using the Osnabrueck Hand Eczema Severity Index (OHSI), and participants answered the Nordic Occupational Skin Questionnaire (NOSQ) and Perceived Stress Scale (PSS). Patch tests were performed using commercial contact allergens. RESULTS: The estimated prevalence of HE (self-reported) was 43.9% (physicians 44.6%; dentists 43.2%). HE was significantly more reported by surgeons than controls (p < 0.004; V = 0.288). Degrees of perceived stress (PSS) did not differ significantly between the groups, though physicians non-surgeons most exhibited high stress (50%), and physicians surgeons most exhibited low stress (22.5%). High stress was associated with 2.5 higher odds for self-reported HE (p = 0.008). Low stress was greater among physicians/dentists who did not report eczema (41.0% vs. 24.6%); moderate stress was more common among those who reported eczema (72.3% vs. 51.8%; p = 0.038; V = 0.210). CONCLUSIONS: Since high stress levels may negatively influence physicians'/dentists' work and quality of life, measures to decrease stress could be introduced into the treatment of healthcare workers who are prone to it.

Shift workers are at increased risk of severe COVID-19 compared with day workers: Results from the international COVID sleep study (ICOSS) of 7141 workers.

The present study had two main aims. First, to investigate whether shift/night workers had a higher prevalence and severity of COVID-19 compared with day workers. Second, to investigate whether people regularly working in face-to-face settings during the pandemic exhibited a higher prevalence and severity of COVID-19 compared with those having no need to be in close contact with others at work. Data consisted of 7141 workers from 15 countries and four continents who participated in the International COVID Sleep Study-II (ICOSS-II) between May and December 2021. The associations between work status and a positive COVID-19 test and several indications of disease severity were tested with chi-square tests and logistic regressions adjusted for relevant confounders. In addition, statistical analyses were conducted for the associations between face-to-face work and COVID-19 status. Results showed that shift/night work was not associated with an increased risk of COVID-19 compared to day work. Still, shift/night workers reported higher odds for moderate to life-threatening COVID-19 (adjusted odds ratio (aOR) = 2.71, 95%-confidence interval = 1.23-5.95) and need for hospital care (aOR = 5.66, 1.89-16.95). Face-to-face work was associated with an increased risk of COVID-19 (aOR = 1.55, 1.12-2.14) but not with higher disease severity. In conclusion, shift/night work was not associated with an increased risk of COVID-19, but when infected, shift/night workers reported more severe disease. Impaired sleep and circadian disruption commonly seen among shift/night workers may be mediating factors. Working face-to-face increased the risk of COVID-19, likely due to increased exposure to the virus. However, face-to-face work was not associated with increased disease severity.

Persistent short nighttime sleep duration is associated with a greater post-COVID risk in fully mRNA-vaccinated individuals.

Short nighttime sleep duration impairs the immune response to virus vaccination, and long nighttime sleep duration is associated with poor health status. Thus, we hypothesized that short (<6 h) and long (>9 h) nighttime sleepers have a higher post-COVID risk than normal nighttime sleepers, despite two doses of mRNA vaccine (which has previously been linked to lower odds of long-lasting COVID-19 symptoms). Post-COVID was defined as experiencing at least one core COVID-19 symptom for at least three months (e.g., shortness of breath). Multivariate logistic regression adjusting for age, sex, BMI, and other factors showed in 9717 respondents (age span 18-99) that two mRNA vaccinations lowered the risk of suffering from post-COVID by about 21% (p < 0.001). When restricting the analysis to double-vaccinated respondents (n = 5918), short and long sleepers exhibited a greater post-COVID risk than normal sleepers (adjusted OR [95%-CI], 1.56 [1.29, 1.88] and 1.87 [1.32, 2.66], respectively). Among respondents with persistent sleep duration patterns during the pandemic compared to before the pandemic, short but not long sleep duration was significantly associated with the post-COVID risk (adjusted OR [95%-CI], 1.59 [1.24, 2.03] and 1.18 [0.70, 1.97], respectively). No significant association between sleep duration and post-COVID symptoms was observed in those reporting positive SARS-CoV-2 test results (n = 538). Our findings suggest that two mRNA vaccinations against SARS-CoV-2 are associated with a lower post-COVID risk. However, this protection may be less pronounced among those sleeping less than 6 h per night. Our findings warrant replication in cohorts with individuals with confirmed SARS-CoV-2 infection.

The association of insomnia with long COVID: An international collaborative study (ICOSS-II).

OBJECTIVE: There is evidence of a strong association between insomnia and COVID-19, yet few studies have examined the relationship between insomnia and long COVID. This study aimed to investigate whether COVID-19 patients with pre-pandemic insomnia have a greater risk of developing long COVID and whether long COVID is in turn associated with higher incident rates of insomnia symptoms after infection. METHODS: Data were collected cross-sectionally (May-Dec 2021) as part of an international collaborative study involving participants from 16 countries. A total of 2311 participants (18-99 years old) with COVID-19 provided valid responses to a web-based survey about sleep, insomnia, and health-related variables. Log-binomial regression was used to assess bidirectional associations between insomnia and long COVID. Analyses were adjusted for age, sex, and health conditions, including sleep apnea, attention and memory problems, chronic fatigue, depression, and anxiety. RESULTS: COVID-19 patients with pre-pandemic insomnia showed a higher risk of developing long COVID than those without pre-pandemic insomnia (70.8% vs 51.4%; adjusted relative risk [RR]: 1.33, 95% confidence interval [CI]: 1.07-1.65). Among COVID-19 cases without pre-pandemic insomnia, the rates of incident insomnia symptoms after infection were 24.1% for short COVID cases and 60.6% for long COVID cases (p < .001). Compared with short COVID cases, long COVID cases were associated with an increased risk of developing insomnia symptoms (adjusted RR: 2.00; 95% CI: 1.50-2.66). CONCLUSIONS: The findings support a bidirectional relationship between insomnia and long COVID. These findings highlight the importance of addressing sleep and insomnia in the prevention and management of long COVID.

Prevention of poisonings by educational intervention aimed at parents of preschool children.

The aim of the study was to assess the effectiveness of the specific design of a poisoning prevention intervention. This controlled before-after study followed Solomon design for educational interventions using two groups (the educational intervention group and the control group). Participants comprised parents of children attending kindergartens under the jurisdiction of the City of Zagreb and in the vicinity of Zagreb. The intervention group (N = 336) underwent an educational intervention during parents' meetings comprising oral presentation by the Croatian Poison Control Centre (CPCC) and distribution of gift packages containing child-proof locks, flyers, and stickers with the CPCC contact number. After the intervention they more frequently started keeping the CPCC's number by their telephone or in the list of important numbers than parents in the control group, and this association remained significant when tested by generalized estimating equations for binary outcomes, after the adjustment for parents' characteristics (age, gender and educational level), and clustered by kindergartens (p < 0.001). This means parents acknowledged the CPCC as an adequate and accessible way for initial management of poisoning incidents.

Harmonized definition of occupational burnout: A systematic review, semantic analysis, and Delphi consensus in 29 countries.

Objective A consensual definition of occupational burnout is currently lacking. We aimed to harmonize the definition of occupational burnout as a health outcome in medical research and reach a consensus on this definition within the Network on the Coordination and Harmonisation of European Occupational Cohorts (OMEGA-NET). Methods First, we performed a systematic review in MEDLINE, PsycINFO and Embase (January 1990 to August 2018) and a semantic analysis of the available definitions. We used the definitions of burnout and burnout-related concepts from the Systematized Nomenclature of Medicine Clinical Terms (SNOMED-CT) to formulate a consistent harmonized definition of the concept. Second, we sought to obtain the Delphi consensus on the proposed definition. Results We identified 88 unique definitions of burnout and assigned each of them to 1 of the 11 original definitions. The semantic analysis yielded a first proposal, further reformulated according to SNOMED-CT and the panelists` comments as follows: "In a worker, occupational burnout or occupational physical AND emotional exhaustion state is an exhaustion due to prolonged exposure to work-related problems". A panel of 50 experts (researchers and healthcare professionals with an interest for occupational burnout) reached consensus on this proposal at the second round of the Delphi, with 82% of experts agreeing on it. Conclusion This study resulted in a harmonized definition of occupational burnout approved by experts from 29 countries within OMEGA-NET. Future research should address the reproducibility of the Delphi consensus in a larger panel of experts, representing more countries, and examine the practicability of the definition.

Weekly alternation of morning and afternoon school start times: implications for sleep and daytime functioning of adolescents.

STUDY OBJECTIVES: To examine sleep patterns of adolescents attending school on alternating morning schedule (MS) and afternoon schedule (AS) and to explore the contribution of sleep characteristics on the AS to prediction of adolescents' daytime functioning. METHODS: The Croatian adaptation of the School Sleep Habits Survey for a two-shift school system was completed by 2,033 students (11-18 years old, 54 per cent females) whose school start times alternated weekly between 08:00 am and 14:00 pm. RESULTS: All age groups of adolescents reported delayed sleep when on the school week with an AS as compared with a MS. The average delay of bedtime was 36 minutes, and delay of wake-up time 121 minutes, which resulted in average sleep durations from 9.80 hours in 11-year olds to 8.39 hours in 18-year olds. Having more delayed wake-up times on the AS predicted more substance use and poorer grades. Having more delayed bedtimes not only predicted poorer grades but also predicted less depressed mood. Obtaining relatively longer sleep on AS predicted lower sleepiness, less depressed mood, and less frequent substance use. CONCLUSIONS: The afternoon school start time enables sleep duration that is in line with adolescent sleep biology and contributes positively to daytime functioning. In many cases, a large delay in wake-up time is observed. At least part of that delay is not associated with adolescents' circadian biology and contributes negatively to some indices of their daytime functioning. Further research of factors associated with extreme delays of sleep and/or interventions that could limit extreme sleep irregularity is required.

Employment status and other predictors of mental health and cognitive functions in older Croatian workers.

The aim of this study was to examine mental health and cognitive functions in older Croatian workers (50-65 years) taking into account their employment status, self-assessed health, and a set of demographic characteristics. We analysed the data collected on 650 older workers (71 % employed) in the Wave 6 of the Survey of Health, Ageing and Retirement in Europe (SHARE). Unemployed workers reported symptoms of loneliness more often than the employed, while in rural areas unemployment was additionally associated with more pronounced symptoms of depression. Feeling of loneliness was also higher in those living without a partner in the household and in those with poorer health. In urban residents symptoms of depression were more severe in women, respondents with higher education, those living without a partner, and those who rated their health as poorer. As for cognitive functions, unemployment significantly predicted poorer subtraction in the rural subsample. Women in general showed less efficient numerical abilities. In the urban subsample poorer numerical abilities were also associated with lower education and living without a partner in the household. Better verbal recall was predicted by higher education and better self-rated memory. Higher scores in verbal fluency were predicted by urban residency and better self-rated health. Our results indicate that the protective factors for good mental health and cognitive functioning in older Croatian workers are being employed, having more education, living with a partner in the household, and being healthier. These findings stress the importance of implementing broader social policy strategies covering employment, education, and health.