Post-injury long-term sickness absence and risk of disability pension: The role of socioeconomic status.

INTRODUCTION: Previous research has identified low socioeconomic status (SES) as a risk factor for long-term sickness absence (LTSA) and disability pension (DP) following trauma. However, most studies lack information on medical diagnoses, limiting our understanding of the underlying factors. To address this gap, we retrieved information about diagnostic causes for receipt of welfare benefits to explore the role of SES in the transition from post-injury LTSA to permanent DP among the working population in Norway. MATERIALS AND METHODS: We conducted a population-based cohort study of all Norwegian residents aged 25-59 years registered with a spell of LTSA due to injury commencing in the period 2000-2003. This cohort was followed through 2014 by linking information on receipt of welfare benefits with sociodemographic data from administrative registers. SES was defined as a composite measure of educational attainment and income level. We used flexible parametric survival models to estimate hazard ratios (HR) with 95 % confidence intervals (CI) for all-cause and diagnosis-specific DP according to SES, adjusting for sex, age, marital status, immigrant status and healthcare region of residence. RESULTS: Of 53,937 adults with post-injury LTSA, 9,665 (18 %) transferred to DP during follow-up. The crude risk of DP was highest for LTSA spells due to poisoning and head injuries. Overall, individuals in the lowest SES category had twice the risk of DP compared to those in the highest SES category (HR = 2.25, 95 % CI 2.13-2.38). The difference by SES was greatest for LTSA due to poisoning and smallest for LTSA due to head injuries. A majority (75 %) of DP recipients had a non-injury diagnosis as the primary cause of DP. The socioeconomic gradient was more pronounced for non-injury causes of DP (HR = 2.47, 95 % CI 2.31-2.63) than for injury causes (HR = 1.73, 95 % CI 1.56-1.92) and was especially steep for DP due to musculoskeletal diseases and mental and behavioural disorders. CONCLUSIONS: The relationship between SES and DP varied by both the type of injury that caused LTSA and the diagnosis used to grant DP, highlighting the importance of taking diagnostic information into account when investigating long-term consequences of injuries.

Psychosocial factors at work and occupational injuries: A prospective study of the general working population in Norway.

BACKGROUND: We examined the effects of psychosocial stressors at work on subsequent injuries, taking into account organizational and mechanical working conditions. METHODS: Randomly drawn from the general population, the cohort comprised respondents with an active employee relationship in 2006 and 2009 (n = 6,745). OUTCOME MEASURE: "Have you, over the past 12 months, afflicted injuries that were caused by an accident at work, and resulting in time off work after the day of the accident?". RESULTS: High job strain (Odds ratio [OR] 2.31; 95% confidence interval [CI] 1.16-4.57), high role conflict (OR 3.01; 95% CI 1.70-5.31), and high emotional demands (OR 1.96; 95% CI 1.15-3.35) predicted injury at follow up (P < 0.01). The population risk attributable to each of these factors ranged from 11% to 14%. CONCLUSIONS: Excess risk of occupational injuries was attributable to job strain, role conflict, and emotional demands. These factors are potentially amenable to preventive measures.

Psychosocial and organizational risk factors for doctor-certified sick leave: a prospective study of female health and social workers in Norway.

BACKGROUND: Doctor-certified sick leave differs substantially across sectors, and among health and social workers, in particular, there is an increased risk. Previous studies have shown that work environmental factors contribute to sick leave. Hence, the identification of specific organizational and psychosocial risk factors for long- term sick leave, taking into account potential confounding related to mechanical risk factors such as lifting and awkward body postures, will be of importance in the work of prevention. METHODS: A randomly drawn population sample of Norwegian residents was interviewed about working conditions in 2009 (n = 12,255; response rate 60.9%). Female health and social care workers (n = 925) were followed in a national registry for subsequent sickness absence during 2010. The outcome of interest was doctor-certified sick leave of 21 days or more (long-term sick leave). Eleven work-related psychosocial and organizational factors were evaluated. RESULTS: In total, 186 persons (20.1%) were classified with subsequent long-term sick leave. After thoroughly adjusting for competing explanatory variables, the most consistent predictors for long-term sick leave were violence and threats of violence (OR = 1.67; 95% CI 1.14-2.45). The estimated population attributable risk for violence and threats of violence was 13%. CONCLUSIONS: The present study among female health and social care workers revealed a substantial relationship between self-reported violence and threats of violence and subsequent long- term sick leave.

Work-related psychosocial risk factors for long-term sick leave: a prospective study of the general working population in Norway.

OBJECTIVE: To examine the effect of work-related psychosocial exposures on long-term sick leave (LTSL) in the general working population. METHODS: A prospective study of the general working population in Norway. Eligible respondents were interviewed in 2009 and registered with at least 100 working days in 2009 and 2010 (n = 6758). The outcome was medically confirmed LTSL of 40 days or more during 2010. RESULTS: In the fully adjusted model, high exposure to role conflict (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.20 to 2.09), emotional demands (OR, 1.32; 95% CI, 1.03 to 1.69), and low supportive leadership (OR = 1.50; 95% CI, 1.15 to 1.96) predicted LTSL. A test for trend was statistically significant for all factors (P ≤ 0.05). We estimated that 15% of LTSL cases were attributable to these factors. CONCLUSIONS: This study underlines the importance of taking into account psychosocial exposures as risk factors for LTSL.

Epidemiology of trauma: a population-based study of geographical risk factors for injury deaths in the working-age population of Norway.

INTRODUCTION: Trauma is a major global cause of morbidity and mortality. Population-based studies identifying high-risk populations and regions may facilitate primary prevention and the development of optimal trauma systems. This study describes the epidemiology of adult trauma deaths in Norway and identifies high-risk areas by assessing different geographical measures of rurality. METHODS: All trauma-related deaths in Norway from 1998 to 2007 among individuals aged 16-66 years were identified by accessing national registries. Mortality data were analysed by linkage to population and geographical data at municipal, county and national levels. Three measures of rurality (centrality, population density and settlement density) were compared based on their association with trauma mortality rates. RESULTS: The study included 8466 deaths, of which 78% were males. The national annual trauma mortality rate was 28.7 per 100,000. Population density was the best predictor of high-risk areas, and there was a consistent inverse relationship between mortality rates and population density. The most rural areas had 52% higher trauma mortality rates compared to the most urban areas. This difference was largely due to deaths following transport-related injury. Seventy-eight per cent of all deaths occurred in the prehospital phase. Rural areas and death following self-harm had higher proportion of prehospital deaths. CONCLUSION: Rural areas, as defined by population density, are at a higher risk of deaths following traumatic injuries and have higher proportions of prehospital deaths and deaths following transport-related injuries. The heterogeneous characteristics of trauma populations with respect to geography and mode of injury should be recognised in the planning of preventive strategies and in the organisation of trauma care.

"Inclusive working life in Norway": a registry-based five-year follow-up study.

BACKGROUND: In 2001, the Norwegian authorities and major labour market partners signed an agreement regarding 'inclusive working life' (IW), whereby companies that participate are committed to reducing sickness absence. Our main aim was to determine the effect of the IW program and work characteristics by gender on long-term (>8 weeks) sickness absence (LSA). METHODS: Self-reported data on work characteristics from the Oslo Health Study were linked to registry-based data on IW status, education and LSA. From 2001-2005, 10,995 participants (5,706 women and 5,289 men) aged 30, 40, 45 and 60 years were followed. A Cox regression was used to compute hazard ratios (HR) for LSA risk. The cohort was divided into an IW group (2,733 women and 2,058 men) and non-IW group (2,973/3,231). RESULTS: 43.2% and 41.6% of women and 22.3%/24.3% of men (IW / non-IW, respectively) experienced at least one LSA. In a multivariate model, statistically significant risk factors for LSA were low education (stronger in men), shift work/night work or rotating hours (strongest in men in the non-IW group), and heavy physical work or work involving walking and lifting (men only and stronger in the non-IW group). Among men who engaged in shift work, the LSA risk was significantly lower in the IW group. CONCLUSIONS: Our results could suggest that IW companies that employ many men in shift work have implemented relevant efforts for reducing sickness absence. However, this study could not demonstrate a significant effect of the IW program on the overall LSA risk.

Social inequalities in road traffic deaths at age 16-20 years among all 611,654 Norwegians born between 1967 and 1976: a multilevel analysis.

BACKGROUND: Road traffic injury is a major cause of death among youths. AIMS: To estimate mortality differences in family socioeconomic position (SEP) and municipal disadvantage level. METHODS: Data on all Norwegians born in 1967-76, gathered from national registries, were linked by a unique national identification number. The 611 654 participants were followed-up for 5 years from age 16 years. Parental education level, father's income level, and proportion of high-income earners in the municipality served as SEP indicators. Associations between SEP and road traffic deaths were analysed by multilevel Poisson regression. Results Road traffic deaths (n=676, rate 22.2 per 100 000 person-years) constituted a major cause of death, of which 91.9% were motor vehicle occupants. SEP distributions differed according to gender and type of motor vehicle crash (collision, non-collision). There was an inverse relationship between municipal proportions of high-income earners and mortality (population attributable fraction (PAF) 0.43, 95% CI 0.30 to 0.53) in all categories of gender-specific crash types. Family SEP gradients were not found except for male non-collision deaths, where increasing mortality was found in association with decreasing parental education level (PAF 0.94, 95% CI 0.59 to 0.99) and increasing paternal income (PAF 0.25, 95% CI 0.06 to 0.40). CONCLUSION: The different SEP patterns for road traffic deaths across gender and motor vehicle crash type illustrate that heterogeneity of social inequalities in health can be found even within narrow age bands and for similar causes of death.

Paediatric trauma mortality in Norway: a population-based study of injury characteristics and urban-rural differences.

INTRODUCTION: Paediatric injury is a major global public health challenge. Epidemiological research is required for effective primary injury prevention and to develop trauma systems for optimal management of childhood injuries. This study aimed to describe the characteristics and geographical distribution of paediatric trauma deaths and to assess the relationship between rural locations and mortality rates. MATERIALS AND METHODS: By accessing national registries, all trauma related deaths of persons aged 0-15 years in Norway from 1998 to 2007 were included. Paediatric trauma mortality rates and injury characteristic were analysed in relation to three different measures of municipal rurality: centrality, population density and settlement density. RESULTS: There were 462 trauma related deaths during the study period and the national annual paediatric mortality rate was 4.81/100000. Rural areas had higher mortality rates, and this difference was best predicted by municipal centrality. Rural trauma was characterised by traffic accidents and deaths that occurred prior to reaching hospital. The rural and northernmost county, Finnmark, had a mortality rate three times the national average. CONCLUSION: Mortality rates after childhood injury are high in rural areas. Substantiated measures of rurality are required for optimal allocation of primary and secondary preventive measures.

The impact of workplace risk factors on long-term musculoskeletal sickness absence: a registry-based 5-year follow-up from the Oslo health study.

OBJECTIVE: To determine the influence of work-related risk factors by gender on long-term sickness absence with musculoskeletal diagnoses (LSM). METHODS: Data from the Oslo Health Study were linked to the historical event database of Statistics Norway. Eight thousand three hundred thirty-three participants were followed from 2001 through 2005. Generalized linear models were used to compute risk differences for LSM. RESULTS: In total, 12.6% of the women and 8.8% of the men experienced at least one LSM. Statistically, significant LSM risk increases between 0.039 and 0.086 in association with work environment were found for heavy physical work, low job control (men only), low support from superior (women only), and having shift/night work (men only). CONCLUSIONS: Women exhibited a higher LSM risk, but the associations with job exposures were stronger for men. This should be addressed when occupational health services give advice on preventive measures.

Risk factors for long-term absence due to psychiatric sickness: a register-based 5-year follow-up from the Oslo health study.

OBJECTIVE: To identify individual and work-related predictors of long-term (>8 weeks) sickness absence with psychiatric diagnoses (LSP). METHODS: Data from the Oslo Health Study (response rate 46%) were linked to public registers. A total of 8333 subjects were followed from 2001 through 2005. Cox regression was used to compute hazard ratios for LSP. RESULTS: At least one LSP was present in 7.8% of women and 3.9% of men. Poor support from superior had an independent and moderate effect. Path and linear regression analyses indicated that the effect of support from superior was mediated through mental distress and not the other way around. Self-reported mental distress had a strong independent effect. CONCLUSIONS: Women had a higher risk of LSP than men. Low education and poor support from superior and mental distress were found to be determinants of LSP.

Influence of early life factors on social inequalities in psychiatric outcomes among young adult Norwegian men.

BACKGROUND: Social inequalities in health can to a substantial degree be explained by social causation. However, indirect selection by early life factors has been suggested. The main aim of this study was to estimate how much adult social gradients in selected psychiatric outcomes depended on parental and individual characteristics in early life. METHODS: The population comprised all males born in Norway 1967-71 (n = 170 678). We compiled data on several social and biological variables from birth onwards from different national registers. Health outcomes were collected from the Cause of Death Register (suicide) and the Labour and Welfare Administration (psychiatric disability, psychiatric sickness absence). Indicator of socio-economic position was education level at the age of 28 years. Men were followed up between 4 and 9 years from the age of 29 years. RESULTS: Crude rates per 100 000 person-years were 21.8 (suicide), 145.7 (disability) and 1164.7 (sickness absence). Social inequalities were strong and consistent for all outcomes. Parental and individual characteristics accounted for a substantial part of the social inequalities in neurosis or personality disorder disability (44.1%) and a moderate role for inequalities in psychiatric sickness absence (25.6%), schizophrenia disability (20.7%) and suicide (17.4%). General ability at the age of 18 years had strongest influence on the social health gradients. Suicide and schizophrenia disability were associated with a combination of high parental and low own education level. CONCLUSION: This study indicates that indirect selection explains a substantial part of social inequalities in certain psychiatric outcomes and that early life prevention is important to reduce health gradients.

Influence of physical, mental and intellectual development on disability in young Norwegian men.

BACKGROUND: Few studies have examined the effects of educational level, intellectual performance, mental function, body mass index and height as well as their interrelationship on the risk of disability pension (DP), taking other life course factors into account. METHODS: We linked several national registers, comprising the Medical Birth Registry, the Central Population Register, the Education Register, the Norwegian Labour and Welfare Organisation and the Norwegian Armed Forces Personnel Data Base, providing personal data on biological and social variables from childhood to young adult age. Participants were all males live born during the period 1967-76, followed up through 2003. Men were excluded who died, emigrated or were granted a DP until age 23 years (when follow-up started) and persons who did not become gainfully employed during the study period. Thus, the study population comprised 302 330 men, and the study outcome was being granted a DP after age 23 years. RESULTS: 3651 men (1.2%) were granted a DP. The DP rate was inversely associated with both educational level and intellectual performance. The adjusted population attributable risks (PAR) values for these two variables were 47% and 35%, respectively. The effect of the other variables was modest. Over- and underweight and short stature were associated with DP, but the effect was largely reduced after adjusting for intellectual performance. Impaired mental function seemed to have an independent effect. CONCLUSION: Receiving an early DP is dependent on several factors acting at different stages of life, above all educational level and intellectual performance. High education can modify some of the effects of low intellectual performance.

Life course determinants for early disability pension: a follow-up of Norwegian men and women born 1967-1976.

BACKGROUND: Most studies on disability pension (DP) have focused on work conditions, socio-economic status and other contemporary factors. We wanted to study possible determinants of an early DP with a life course perspective within a large register-based cohort, with a main focus on the biological and social factors from childhood. METHODS: We established a longitudinal, population-based cohort of all persons liveborn in Norway between 1967 and 1976. Through linkage between several national registers we obtained personal data on biological/health related as well as social background factors. After excluding persons who died, emigrated or were granted a DP before age 20 years (at which age follow-up started) and persons who did not become gainfully employed during the study period, the study population consisted of 595,393 persons. They were categorized into four strata according to gender and educational attainment. Adjusted hazard ratios (HR) for granting a DP until the end of 2003 and the corresponding population attributable risks (PAR) were computed. RESULTS: A total of 9,649 persons (1.6%) were granted a DP during follow-up. The disability risk was slightly higher among women than among men (1.7% vs. 1,5%). The following PARs were found: birth weight below the mean 5.7%, chronic childhood disease 6.8%, maternal marital status 4.4% and parental disability 8.8%. Low educational achievement was highly associated with DP, with a PAR more than twice as high as the overall PAR for the childhood factors. CONCLUSIONS: Early DP is associated with several biological and social background factors from childhood. It also shows a strong dependency on educational achievement.

[Risk factors for accidental injuries in the construction industry]. / Risikofaktorer for ulykkesskader i bygge- og anleggsbransjen.

BACKGROUND: The construction industry is prone to accidents. In Norway there is little research-based knowledge on accident pattern and risk factors. The main objective of the study was to examine whether in-depth studies of accidents in this industry, leading to injuries registered by the health services, could identify preventable risk factors and preventive measures. MATERIAL AND METHODS: 50 accidents in the construction industry were thoroughly investigated. All had led to serious personal injury. Patients were interviewed after treatment in emergency wards and hospitals in Oslo, and inspections of the accident sites were performed. An interdisciplinary expert group discussed the accidents in order to identify risk factors and suggest preventive measures. The accident reports in the study were compared to reports from the Labour Inspectorate on the same accidents. RESULTS: The investigation identified several risk factors, and a number of detailed preventive measures were proposed. We submitted these proposals to the authorities and organisations involved. Accidents because of time pressure and electricity were two main groups. More than one third of the respondents said that time pressure had contributed to the accident. Accident risk caused by time pressure can be reduced by avoiding piecework contracts, unrealistic time limits, and the use of day penalties for breach of contract. Possible preventive measures for electric injuries imply modification of the reporting system and of the work organisation so that workers can comply with the regulations more easily. The study reports generally contained more information of relevance for prevention than the routine reports from the Labour Inspectorate did. For accidents reported by the Inspectorate to the police, their reports were more informative than the study reports. INTERPRETATION: By the method presented, we obtained detailed information about accidents and preventable risk factors, so that preventive measures could be proposed. The method can also be used for other types of accidents.

A two-step medically based injury surveillance system--experiences from the Oslo injury register.

This paper presents a two-step injury surveillance system. In the first step, limited data (a minimum data set) on all (or a representative sample of all) injuries to residents and non-residents within a defined geographical area were obtained using routine collection procedures within the medical care system. The second step involved periodically sampling of specific injuries, injured persons, or places for in-depth investigations from the database established by the first step, or selecting relevant injured persons seeking treatment in the medical care system, to collect many data (an expanded data set) on a limited number of injuries. This system was implemented in Oslo. Data from about 48,000 injuries were collected annually. Two in-depth investigations of serious occupational injuries were carried out. The first involved 223 cases and the second, 50 cases. Some in-site studies were included. Experiences from the implementation in Oslo suggest that this system can function in the medical care system and provide data required for making estimates of injury incidence rates, establishing trends, and on contributing factors to injuries. A crucial factor in the success of the first part of such a system is to have enough resources for continuous quality control and feedback to personnel involved in the registration of data. Combining the registered data from general practitioners, accident and emergency departments, hospitals and notifications of fatalities in Oslo, and on assessments of the number of injuries treated by private clinics and occupational health centres in Oslo, and in the health care system outside of Oslo, leads to the conclusion that 11.9% of the residents of Oslo will annually be treated for an injury.

[Underreporting of occupational injuries to the Labour Inspection]. / Underrapportering av arbeidsskader til Arbeidstilsynet.

BACKGROUND: The Labour Inspection investigates occupational accidents and publishes injury statistics annually. Information is based upon two main sources: Copies of reports to the National Insurance Service and mandatory reports from employers to the Labour Inspection. MATERIAL AND METHODS: Occupational injuries treated by Oslo Emergency Ward and Oslo Ambulance Service during a period of three months were compared with injuries recorded by the Labour Inspection. RESULTS: Four months after the end of the study period, the Labour Inspection had received reports from the National Insurance Service on 150 (13%) of the 1,153 injuries recorded by Oslo Emergency Ward/Oslo Ambulance Service. Among all injuries registered, 208 were serious according to the criteria of the Labour Inspection. Only 19 (9%) of these were reported directly to the Labour Inspection from employers in accordance with the legal requirement. The study recorded 17 serious injuries caused by violence affecting employees; none of these were reported directly to the Labour Inspection. INTERPRETATION: Data on occupational injuries collected by the Labour Inspection are far from complete. In Oslo alone, the Labour Inspection may annually overlook some 900-1,000 serious injuries. Data quality can be improved and delayed reporting avoided by using information from doctors and medical institutions that provide treatment.

[Occupational injuries in Oslo: a study of occupational injuries treated by the Oslo Emergency Ward and Oslo Ambulance Service]. / Arbeidsskader behandlet ved Legevakten i Oslo og Ambulansetjenesten.

BACKGROUND: There is little reliable information about the incidence and severity of occupational injuries in Norway. MATERIAL AND METHODS: Occupational injuries occurring at worksites in Oslo and treated by Oslo Emergency Ward or Oslo Ambulance Service were recorded over a period of three months. Patients with serious injuries were interviewed about the accident. RESULTS: 1153 injury incidents were registered, 229 (20%) of which were considered serious. Median age of patients was 32 years. Estimated annual incidence of injuries at worksites in Oslo treated by Oslo Emergency Ward/Oslo Ambulance Service was 14 per 1000 employees, for all injuries in Oslo requiring treatment, 20 per 1000 employees. Men had three times the incidence of women. The incidence was highest in the youngest age groups. Of those with serious injuries, 30% had a non-Scandinavian language as their first language. Electricians, carpenters and police officers had the highest observed incidences. 87 injuries (8%) were caused by violence. INTERPRETATION: The incidence of occupational injuries in Oslo is reduced by about 40% since the 1970s. There is, however, no reduction for women. Construction workers are still at high risk. Workers of non-Scandinavian origin are also at high risk, probably because of selection into high-risk occupations. The injury register provides a good overview, but in-depth studies are needed to identify specific risk factors.