Immunohistochemical double nuclear staining for cell-specific automated quantification of the proliferation index - A promising diagnostic aid for melanocytic lesions

AIMS

Pathologists often use immunohistochemical staining of the proliferation marker Ki67 in their diagnostic assessment of melanocytic lesions. However, the interpretation of Ki67 can be challenging. We propose a new workflow to improve the diagnostic utility of the Ki67-index. In this workflow, Ki67 is combined with the melanocytic tumour-cell marker SOX10 in a Ki67/SOX10 double nuclear stain. The Ki67-index is then quantified automatically using digital image analysis (DIA). The aim of this study was to optimise and test three different multiplexing methods for Ki67/SOX10 double nuclear staining.

METHODS

Multiplex immunofluorescence (mIF), multiplex immunohistochemistry (mIHC), and multiplexed immunohistochemical consecutive staining on single slide (MICSSS) were optimised for Ki67/SOX10 double nuclear staining. DIA applications were designed for automated quantification of the Ki67-index. The methods were tested on a pilot case-control cohort of benign and malignant melanocytic lesions (n = 23).

RESULTS

Using the Ki67/SOX10 double nuclear stain, malignant melanocytic lesions could be completely distinguished from benign lesions by the Ki67-index. The Ki67-index cut-offs were 1.8% (mIF) and 1.5% (mIHC and MICSSS). The AUC of the automatically quantified Ki67-index based on double nuclear staining was 1.0 (95% CI: 1.0;1.0), whereas the AUC of conventional Ki67 single-stains was 0.87 (95% CI: 0.71;1.00).

CONCLUSIONS

The novel Ki67/SOX10 double nuclear stain highly improved the diagnostic precision of Ki67 interpretation. Both mIHC and mIF were useful methods for Ki67/SOX10 double nuclear staining, whereas the MICSSS method had challenges in the current setting. The Ki67/SOX10 double nuclear stain shows potential as a valuable diagnostic aid for melanocytic lesions.

A multidimensional analysis reveals distinct immune phenotypes and tertiary lymphoid structure-like aggregates in the bone marrow of pediatric acute myeloid leukemia

Because of the low mutational burden, children with acute myeloid leukemia (AML) are thought to have a 'cold' tumor microenvironment and consequently, a low likelihood of response to T cell-directed immunotherapies. Here, we provide a multidimensional overview of the tumor immune microenvironment in newly diagnosed pediatric AML. On a cohort level, we demonstrate wide variation in T cell infiltration with nearly one-third of cases harboring an immune-infiltrated bone marrow. These immune-infiltrated cases are characterized by a decreased abundance of M2-like macrophages, which we find to be associated with response to T cell-directed immunotherapy in adult AML. On an organizational level, we reveal the composition of spatially organized immune aggregates in pediatric AML, and show that in the adult setting such aggregates in post-treatment bone marrow and extramedullary sites associate with response to ipilimumab-based therapy. Altogether, our study provides immune correlates of response to T cell-directed immunotherapies and indicates starting points for further investigations into immunomodulatory mechanisms in AML.

Fueling the flames of colon cancer – does CRP play a direct pro-inflammatory role?

Background

Systemic inflammation, diagnostically ascribed by measuring serum levels of the acute phase reactant C-reactive protein (CRP), has consistently been correlated with poor outcomes across cancer types. CRP exists in two structurally and functionally distinct isoforms, circulating pentameric CRP (pCRP) and the highly pro-inflammatory monomeric isoform (mCRP). The aim of this pilot study was to map the pattern of mCRP distribution in a previously immunologically well-defined colon cancer (CC) cohort and explore possible functional roles of mCRP within the tumor microenvironment (TME).

Methods

Formalin-fixed, paraffin-embedded (FFPE) tissue samples from 43 stage II and III CC patients, including 20 patients with serum CRP 0-1 mg/L and 23 patients with serum CRP >30 mg/L were immunohistochemically (IHC) stained with a conformation-specific mCRP antibody and selected immune and stromal markers. A digital analysis algorithm was developed for evaluating mCRP distribution within the primary tumors and adjacent normal colon mucosa.

Results

mCRP was abundantly present within tumors from patients with high serum CRP (>30 mg/L) diagnostically interpreted as being systemically inflamed, whereas patients with CRP 0-1 mg/L exhibited only modest mCRP positivity (median mCRP per area 5.07‰ (95%CI:1.32-6.85) vs. 0.02‰ (95%CI:0.01-0.04), p<0.001). Similarly, tissue-expressed mCRP correlated strongly with circulating pCRP (Spearman correlation 0.81, p<0.001). Importantly, mCRP was detected exclusively within tumors, whereas adjacent normal colon mucosa showed no mCRP expression. Double IHC staining revealed colocalization of mCRP with endothelial cells and neutrophils. Intriguingly, some tumor cells also colocalized with mCRP, suggesting a direct interaction or mCRP expression by the tumor itself.

Conclusion

Our data show that the pro-inflammatory mCRP isoform is expressed in the TME of CC, primarily in patients with high systemic pCRP values. This strengthens the hypothesis that CRP might not only be an inflammatory marker but also an active mediator within tumors.

The effect of COVID-19 on schoolteachers’ emotional reactions and mental health

Background

Schoolteachers play a major role in the society's response to the COVID-19 pandemic. When schools are open teachers are responsible for hindering spread of SARS-CoV-2, while carrying out their core task of teaching. This double role as well as the risk of infection may affect mental health in this occupational group. Therefore, we investigated schoolteachers' emotional reactions to COVID-19 and mental health during three phases of the COVID-19 pandemic in Denmark. We further analyzed if teachers, who belonged to a COVID-19 risk group, had more emotional reactions and poorer mental health than “non-risk” groups.

Methods

We collected questionnaire data in May, June, and November-December 2020 and used data from 2665 teachers employed at public schools (871 individuals participated in all three surveys). Participants reported their fear of infection, fear of transmission of infection to their home or pupils, perceived burnout and stress, and worries about their ability to manage the working conditions. We also had information about COVID-19 risk group status, sex, age, organization of teaching (physical presence or remote teaching), and the pupils' grade. We estimated prevalence ratios and took repeated measures into account.

Results

Fear of infection and transmission of infection as well as burnout, stress, and worries increased statistically significantly with 27-84% from May to November-December 2020 (p < 0.05). We also found that teachers, who were particularly vulnerable to the adverse consequences of COVID-19, had the highest prevalence of fear of infection and poor mental health.

Conclusions

The dual role of teaching and virus control along with concerns regarding the health consequences of an infection may contribute to the observed increase in emotional reactions to COVID-19 and poor mental health from the beginning of the pandemic to the beginning of the second wave.

Key messages

The results raise attention to the working conditions, exposure to infection and mental health of teachers being in the frontline when schools were open during the COVID-19 pandemic.

School teachers play a major role in pandemic control along with teaching obligations, which warrants allocation of resources, clear guidelines, and possibilities for protection from infection.

The Hidradenitis Suppurativa Quality of Life (HiSQOL) score: development and validation of a measure for clinical trials

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic, inflammatory condition that can have a large negative impact on health-related quality of life (HRQOL). A reliable and validated measure of HS-specific HRQOL in clinical studies is needed.

OBJECTIVES

To develop and validate the Hidradenitis Suppurativa Quality Of Life (HiSQOL©) scale, for clinical trial measurement of HS-specific HRQOL.

METHODS

In stage 1, qualitative concept elicitation interviews were conducted with patients with HS in Denmark (n = 21) and the U.S.A. (n = 21). In stage 2, cognitive debriefing interviews were performed with U.S. (n = 30) and Danish patients with HS (n = 30). In stage 3 an observational study of 222 patients with HS in the U.S.A. was conducted for item reduction, measure validation and assessment of psychometric properties. In stage 4, an observational study of 215 patients with HS in Denmark was conducted to confirm the psychometric structure derived in stage 3. In both studies the Dermatology Life Quality Index, Hospital Anxiety and Depression Scale and numerical rating scale for pain were also included.

RESULTS

In concept elicitation, 99 items were generated, which were reduced to 41 after removing duplicates. In cognitive debriefing, two items were added and one item removed. A 42-item instrument was psychometrically assessed. Based on psychometric analyses and patient input, the instrument was reduced to 17 items that had strong psychometric properties in both the U.S. and Danish samples.

CONCLUSIONS

The HiSQOL is a reliable and valid instrument to measure HS-specific HRQOL in clinical trials.

Glenohumeral and scapulothoracic strength impairments exists in patients with subacromial impingement, but these are not reflected in the shoulder pain and disability index

BACKGROUND

Pain and loss of function are cardinal symptoms associated with Subacromial impingement syndrome (SIS), while the presence and magnitude of deficits in strength and range of motion (ROM) are largely undescribed in non-athletic patients with SIS. Moreover, the relevance of impairments in strength and ROM to patient-reported shoulder function is not well described, even though testing of strength is recommended in clinical guidelines. The purpose of this study was, first, to investigate impairments in glenohumeral and scapulothoracic strength and in abduction and internal rotation ROM in patients with SIS. Secondly, to investigate the influence of these impairments on patient-reported shoulder function.

METHODS

Cross-sectional study based on a consecutive cohort of 157 patients referred to specialist examination and diagnosed with shoulder impingement (SIS) using predefined validated diagnostic criteria. Prior to specialist examination, questionnaires regarding shoulder function (Shoulder Pain And Disability Index, SPADI) demographics and kinesiophobia (TSK-11) were collected, and shoulder strength and ROM was measured by trained testers, with the patient reporting pain levels during testing and for the last week. Impairments in strength (abduction, external-rotation, (protraction and horizontal-extension) and ROM (abduction and internal rotation) were investigated in patients with unilateral shoulder pain, using one-sample t-tests. SPADI total score (SPADI) and SPADI function score (SPADI-F), were chosen as dependent variables in multiple regressions to investigate the influence of impairments on patient-reported shoulder function. Independent variables of interest were; strength in abduction and external rotation, abduction ROM, pain-during-tests, pain-last-week and kinesiophobia.

RESULTS

Significant impairments were found for all impairment tests, but most pronounced for glenohumeral strength and abduction ROM (29-33% deficits), and less for scapulothoracic strength and internal rotation ROM (8-18% deficits). Pain variables influenced SPADI and SPADI-F score to a high degree (R² = 23.4-31.6%, p < 0.001), while strength and ROM did not.

CONCLUSION

Substantial strength and ROM impairments were found in patients with SIS. Only pain significantly influenced patient-reported function, while impairments did not. As SPADI score does not reflect the substantial strength and ROM impairments in external rotation and abduction observed in patients with SIS, supplemental assessment of these impairments seems important.

Spanish version of the Actinic Keratosis Quality of Life questionnaire

BACKGROUND

Patient-reported outcome measures are very important outcomes. For specific diseases, health-related quality of life-instruments (HRQoL) are increasingly used to provide data on patients' overall perceptions of the course of a given disease. Actinic keratoses (AKs) are common keratotic lesions that occur on chronically sunlight-exposed skin. Only few studies regarding HRQoL in AKs have been made.

OBJECTIVE

In order to be able to compare HRQoL among different countries and cultures, we aimed to translate and validate the Actinic Keratosis Quality of Life (AKQoL) questionnaire into Spanish and quantify the impairment caused by AKs in Spanish patients.

METHODS

The AKQoL was translated. Then, 15 patients with AKs were interviewed to ensure cultural adaption before it was tested in one hundred patients with AK lesions at the Melanoma Unit of Hospital Clinic in Barcelona.

RESULTS

Validation showed high interitem correlations, as well as a high correlation of each item and the total score. Internal consistency (Cronbach's coefficient alpha) was also high at 0.91 and an alpha value of 0.90 at retest. The test-retest correlation was 0.96, and the intraclass coefficient was 0.98.

CONCLUSION

The presented data support the AKQoL Spanish version as a valid and reliable HRQoL questionnaire for the description of AK-related QoL and may provide a method for comparison of AK specific QoL between different cultures and countries.

Self-rated health as a predictor of outcomes of type 2 diabetes patient education programmes in Denmark

OBJECTIVE

To explore if self-rated health (SRH) can predict differences in outcomes of patient education programmes among patients with type 2 diabetes over time.

STUDY DESIGN

This is an observational cohort study conducted among 83 patients with type 2 diabetes participating in patient education programmes in the Capital Region of Denmark.

METHODS

Questionnaire data were collected by telephone interview at baseline and 2 weeks (77 participants, 93%) and 12 months (66, 80%) after the patient education ended. The seven-scale Health Education Impact Questionnaire (HeiQ) was the primary outcome. The independent variable was SRH, which was dichotomized into optimal or poor SRH. Changes over time were assessed using mean values and standard deviation (SD) at each time point and Cohen effect sizes. Odds ratios and 95% confidence intervals were calculated for the likelihood of having poor SRH for each baseline sociodemographic and health-related variable.

RESULTS

Twelve months after patient education programmes, 60 (72%) patients with optimal SRH at baseline demonstrated increased self-management skills, overall acceptance of chronic illness, positive social interaction with others, and improved emotional well-being. Participants with poor SRH (23, 28%) reported no improvements over time. Not being married (odds ratio [OR] 7.79, P < 0.001), living alone (OR 4.93, P = 0.003), having hypertension (OR 8.00, P = 0.031), and being severely obese (OR 4.07, P = 0.009) were significantly associated with having poor SRH. After adjusting for sex, age and vocational training, marital status (OR 9.35, P < 0.001), cohabitation status (OR = 4.96, P = 0.005) and hypertension (OR 10.9, P = 0.03) remained associated with poor SRH.

CONCLUSIONS

We found a strong association between SRH and outcomes of patient education, as measured by the HeiQ, at 12 months. Only participants with optimal SRH appeared to benefit from patient education. Other patient characteristics may be responsible to explain the observed difference between patients with optimal and poor SRH.

Efficacy of recreational football on bone health, body composition, and physical functioning in men with prostate cancer undergoing androgen deprivation therapy: 32-week follow-up of the FC prostate randomised controlled trial

Androgen deprivation therapy (ADT) for prostate cancer (PCa) impairs musculoskeletal health. We evaluated the efficacy of 32-week football training on bone mineral density (BMD) and physical functioning in men undergoing ADT for PCa. Football training improved the femoral shaft and total hip BMD and physical functioning parameters compared to control.

INTRODUCTION

ADT is a mainstay in PCa management. Side effects include decreased bone and muscle strength and increased fracture rates. The purpose of the present study was to evaluate the effects of 32 weeks of football training on BMD, bone turnover markers (BTMs), body composition, and physical functioning in men with PCa undergoing ADT.

METHODS

Men receiving ADT >6 months (n = 57) were randomly allocated to a football training group (FTG) (n = 29) practising 2-3 times per week for 45-60 min or to a standard care control group (CON) (n = 28) for 32 weeks. Outcomes were total hip, femoral shaft, femoral neck and lumbar spine (L2-L4) BMD and systemic BTMs (procollagen type 1 amino-terminal propeptide, osteocalcin, C-terminal telopeptide of type 1 collagen). Additionally, physical functioning (postural balance, jump height, repeated chair rise, stair climbing) was evaluated.

RESULTS

Thirty-two-week follow-up measures were obtained for FTG (n = 21) and for CON (n = 20), respectively. Analysis of mean changes from baseline to 32 weeks showed significant differences between FTG and CON in right (0.015 g/cm(2)) and left (0.017 g/cm(2)) total hip and in right (0.018 g/cm(2)) and left (0.024 g/cm(2)) femoral shaft BMD, jump height (1.7 cm) and stair climbing (-0.21 s) all in favour of FTG (p < 0.05). No other significant between-group differences were observed.

CONCLUSIONS

Compared to standard care, 32 weeks of football training improved BMD at clinically important femoral sites and parameters of physical functioning in men undergoing ADT for PCa.

Self-reported previous knee injury and low knee function increase knee injury risk in adolescent female football

Knee injuries are common in adolescent female football. Self-reported previous knee injury and low Knee injury and Osteoarthritis Outcome Score (KOOS) are proposed to predict future knee injuries, but evidence regarding this in adolescent female football is scarce. The aim of this study was to investigate self-reported previous knee injury and low KOOS subscale score as risk factors for future knee injuries in adolescent female football. A sample of 326 adolescent female football players, aged 15-18, without knee injury at baseline, were included. Data on self-reported previous knee injury and KOOS questionnaires were collected at baseline. Time-loss knee injuries and football exposures were reported weekly by answers to standardized text-message questions, followed by injury telephone interviews. A priori, self-reported previous knee injury and low KOOS subscale scores (< 80 points) were chosen as independent variables in the risk factor analyses. The study showed that self-reported previous knee injury significantly increased the risk of time-loss knee injury [relative risk (RR): 3.65, 95% confidence (CI) 1.73-7.68; P < 0.001]. Risk of time-loss knee injury was also significantly increased in players with low KOOS subscale scores (< 80 points) in Activities of Daily Living (RR: 5.0), Sport/Recreational (RR: 2.2) and Quality of Life (RR: 3.0) (P < 0.05). In conclusion, self-reported previous knee injury and low scores in three KOOS subscales significantly increase the risk of future time-loss knee injury in adolescent female football.

Football training improves lean body mass in men with prostate cancer undergoing androgen deprivation therapy

Androgen deprivation therapy (ADT) remains a cornerstone in the management of patients with prostate cancer (PCa) despite adverse effects on body composition and functional parameters. We compared the effects of football training with standard care in PCa patients managed with ADT (> 6 months). Fifty-seven men aged 67 (range: 43-74) were randomly assigned to a football group (FG, n = 29) or a usual care control group (CON, n = 28). The primary outcome was change in lean body mass (LBM) assessed by dual-energy X-ray absorptiometry scanning. Secondary outcomes included changes in knee-extensor muscle strength (one repetition maximum), fat percentage, and maximal oxygen uptake (VO2max ). Mean heart rate during training was 137.7 (standard deviation 13.7) bpm or 84.6 (3.9)% HRmax. In FG, LBM increased by 0.5 kg [95% confidence interval (CI) 0.1-0.9; P = 0.02] with no change in CON (mean group difference 0.7 kg; 95% CI 0.1-1.2; P = 0.02). Also, muscle strength increased in FG (8.9 kg; 95% CI 6.0-11.8; P < 0.001) with no change in CON (mean group difference 6.7 kg; 95% CI 2.8-10.7; P < 0.001). In FG, VO2max increased (1.0 mL/kg/min; 95% CI 0.2-1.9; P = 0.02) and fat percentage tended to decrease (0.7%; 95%CI 1.3-0.0; P = 0.06), but these changes were not significantly different from CON. In conclusion, football training over 12 weeks improved LBM and muscle strength compared with usual care in men with prostate cancer receiving ADT.

Socio-demographic factors, comorbidity and diagnostic delay among women diagnosed with cervical, endometrial or ovarian cancer

This study investigates the association between socio-demographic factors, comorbidity and diagnostic delay among gynaecological cancer patients. A questionnaire was sent to 1052 women diagnosed with cervical, endometrial or ovarian cancer between October 2006 and December 2007 in Denmark. Long patient delays were associated with diagnosis with a greater risk of experiencing long delays among women diagnosed with cervical and endometrial cancer as opposed to ovarian cancer. The risk of experiencing long GP referral delays was associated with residential area, with a greater risk of long delays in rural vs. urban areas. Long gynaecologist appointment delays were associated with younger age, while long secondary care delays were associated with living in a capital area and having comorbidity. Long total delays were associated with diagnosis with greater risk of experiencing long delays among women diagnosed with cervical and endometrial cancer as opposed to ovarian cancer, and with working as opposed to being retired. In conclusion, this study found that socio-demographic factors and comorbidity play a role in the probability of experiencing long delays. If delays in diagnosis are to be reduced, there must be increased recognition of the significance of symptoms among patients and interventions aimed at ensuring timely care by specialists.

Activation of the nuclear receptor PPARγ by metabolites isolated from sage (Salvia officinalis L.)

ETHNOPHARMACOLOGICAL RELEVANCE

Salvia officinalis has been used as a traditional remedy against diabetes in many countries and its glucose-lowering effects have been demonstrated in animal studies. The active compounds and their possible mode of action are still unknown although it has been suggested that diterpenes may be responsible for the anti-diabetic effect of Salvia officinalis.

AIM OF THE STUDY

To investigate whether the reported anti-diabetic effects of Salvia officinalis are related to activation of the nuclear receptor peroxisome proliferator-activated receptor (PPAR)γ and to identify the bioactive constituents.

MATERIALS AND METHODS

From a dichloromethane extract of Salvia officinalis able to activate PPARγ several major metabolites were isolated by chromatographic techniques. To assess bioactivity of the isolated metabolites a PPARγ transactivation assay was used.

RESULTS

Eight diterpenes were isolated and identified including a new abietane diterpene being the epirosmanol ester of 12-O-methyl carnosic acid and 20-hydroxyferruginol, which was isolated from Salvia officinalis for the first time, as well as viridiflorol, oleanolic acid, and α-linolenic acid. 12-O-methyl carnosic acid and α-linolenic acid were able to significantly activate PPARγ whereas the remaining metabolites were either unable to activate PPARγ or yielded insignificant activation.

CONCLUSIONS

Selected metabolites from Salvia officinalis were able to activate PPARγ and hence, the anti-diabetic activity of this plant could in part be mediated through this nuclear receptor.

Socio-economic differences in the association between sickness absence and mortality: the prospective DREAM study of Danish private sector employees

OBJECTIVES

To examine duration of sickness absence as a risk marker for future mortality by socio-economic position among all private sector employees in Denmark in 1998-2004.

METHODS

All residents in Denmark employed in the private sector receiving sickness absence compensation in 1998 were investigated in a prospective cohort study. 236 207 persons (38.2% women, 61.8% men, age range 18-65, mean age 37.8 years) alive on 1 January 2001 were included in the study. Mortality from 1 January 2001 to 31 December 2004 was assessed using national register data. Deaths in 1999 and 2000 were excluded to determine the status of sickness absence duration as an early risk marker. For analyses within occupational grades, data were available for a sub-population of 137 607 study participants.

RESULTS

3040 persons died during follow-up. The age-adjusted risk of future mortality increased by duration of sickness absence in a graded fashion among men and non-blue collar workers. Among women and blue collar workers, there was no association of mortality with duration of sickness absences below 6 weeks. However, employees with > or =6 weeks of absence compared to those with 1-week absence had a substantial excess risk of death in all groups: adjusted hazard ratio 2.2 (95% CI 1.8 to 2.7) for women, 2.1 (95% CI 1.8 to 2.4) for men, 3.7 (95% CI 1.9 to 7.2) in white collar occupations, 3.3 (95% CI 2.2 to 5.0) in intermediate grade occupations and 2.0 (95% CI 1.7 to 2.3) in blue collar occupations.

CONCLUSION

Administratively collected data on sickness absence compensation for periods > or =6 weeks identified "at risk" groups for future excess mortality in male and female private sector employees across occupational grade levels.

A 15-year prospective study of shift work and disability pension

Objective:

To estimate the hazard ratio for disability pension associated with shift work.

Methods:

Cohorts of shift and day workers were identified in three waves of the Danish Work Environment Cohort Study and followed up for incidence of disability pension in a national register of social transfer payment. A total of 3980 female and 4025 male employees were included in the cohorts. Information about shift work status, age, smoking habits, body mass index and ergonomic work environment were updated according to responses in subsequent waves of the survey when possible. Respondents reporting shift work were classified as shift workers in the following waves as well. Respondents were followed in the register from the time of first interview and were censored at the time of their 60th birthday, emigration, death or end of follow-up (18 June 2006). The authors used the Cox proportional hazards model to estimate hazard ratios for incidence of disability pension and 95% confidence intervals.

Results:

The authors observed 253 new disability pensions among women and 173 among men during 56 903 and 57 886 person-years at risk respectively, Among women, shift work predicted disability after adjustment for age, general health and socioeconomic status HR 1.39 (95% CI 1.07 to 1.82). After further adjustment for body mass index, smoking habits, socioeconomic status and ergonomic exposures the association remained statistically significant HR 1.34 (95% CI 1.02 to 1.75). Shift work was not associated with disability among men.

Conclusion:

Shift work might be moderately associated with disability pension among women; however, more powerful studies are needed to establish the possible association.

Eye blink frequency during different computer tasks quantified by electrooculography

The purpose of the study was to evaluate electrooculography (EOG) as an automatic method to measure the human eye blink frequency (BF) during passive and interactive computer tasks performed at two screen heights. Ten healthy subjects (5 males and 5 females) participated in the study in a 23 degrees C temperature and 30-35% relative humidity controlled simulated office environment. Each test subject completed a 2 x 10 min active task of computer work and a 3 x 10 min passive task of watching a film on a video display unit (VDU). Both tasks included two viewing angles: standard (the monitors' upper edge was in the same height as the subjects' eyes) and low (lowered by 25 degrees). EOG signals were recorded with two Ag/AgCl surface electrodes positioned above and below the right eye, and a reference electrode was placed behind the ear. The experiments were video filmed, and eye blinks were counted manually from the video recordings and compared to the EOG measurements. The method showed a high validity to detect blinks during computer work: 95.4% of the blinks were retrieved by the EOG method and very few artefacts from eye movements were erroneously classified as eye blinks (2.4%). By use of the EOG method, the computer task was found to significantly decrease the BF by 69% compared to the passive task (P < 0.001), and a small decrease (12-14%) was found by lowering the viewing angle by 25 degrees.

Burnout as a predictor of self-reported sickness absence among human service workers: prospective findings from three year follow up of the PUMA study

AIM

To investigate whether burnout predicts sickness absence days and sickness absence spells in human service workers.

METHOD

A total of 824 participants from an ongoing prospective study in different human service sector organisations were eligible for the three year follow up analysis. Burnout was measured with the work related burnout scale of the Copenhagen Burnout Inventory. Sickness absence was measured with self-reported number of days and spells during the last 12 months before the baseline and the follow up survey. A Poisson regression model with a scale parameter was used to account for over dispersion. A linear regression model was used for analysing changes in burnout and absence between baseline and follow up.

RESULTS

Burnout was prospectively associated with both sickness absence days and sickness absence spells per year. Differences in sickness absence days varied from a mean of 5.4 days per year in the lowest quartile of the work related burnout scale to a mean of 13.6 in the highest quartile. An increase of one standard deviation on the work related burnout scale predicted an increase of 21% in sickness absence days per year (rate ratio 1.21, 95% CI 1.11 to 1.32) after adjusting for gender, age, organisation, socioeconomic status, lifestyle factors, family status, having children under 7 years of age, and prevalence of diseases. Regarding sickness absence spells, an increase of one standard deviation on the work related burnout scale predicted an increase of 9% per year (rate ratio 1.09, 95% CI 1.02 to 1.17). Changes in burnout level from baseline to follow up were positively associated with changes in sickness absence days (estimate 1.94 days/year, SE 0.63) and sickness absence spell (estimate 0.34 spells/year, SE 0.08).

CONCLUSION

The findings indicate that burnout predicts sickness absence. Reducing burnout is likely to reduce sickness absence.