Uføretrygdede med ryggplager tilbake i arbeid

Sammendrag
Artikkelen gjengir essensen av en doktorgradsavhandling som vurderte mulighetene for å hjelpe en gruppe uføretrygdede med ryggplager tilbake til arbeidslivet. Korsryggsmerter er i dag en av de vanligste årsaker til nedsatt funksjon og arbeidsevne. Økningen i uførhet på grunn av korsryggsmerter har store samfunnsøkonomiske og individuelle konsekvenser, og svært få som har varige uføreytelser gjenopptar arbeidet. En gruppe personer som hadde mottatt uføretrygd i flere år med en rygglidelse som årsak til sin uførhet ble undersøkt. Avhandlingen inneholder tre artikler: Artikkel I var en kvalitativ studie som undersøkte opplevde barrierer mot å vende tilbake til arbeid. Artikkel II var en tverrsnittsstudie som undersøkte fysisk og psykisk funksjonsevne samt sammenhengen mellom funksjon og motivasjon for arbeid. Artikkel III var en randomisert, kontrollert studie der effekten av et kortvarig, arbeidsrelatert tiltak ble evaluert.

Abstract
This article presents the essence of a PhD-thesis which evaluated the possibility to bring a group of disability pensioners with back pain to return to work. Low back pain is one of the most common conditions leading to disability and early retirement. The socioeconomic and individual consequences are huge, and the chance of ever returning to work after becoming a disability pensioner is very small. A group of persons on long-term disability pension due to back pain were investigated. The thesis consists of three papers: Paper I was a qualitative study exploring barriers towards work as perceived by the pensioners. Paper II was a cross-sectional study investigating physical and mental functioning and the association between functioning and motivation for returning to work. Paper III was a randomized controlled trial examining the effect of a brief vocational-oriented intervention.

Artikkelen er en direkte dobbeltpublisering av Introduction og gjengir kort studiene i avhandlingen: Magnussen LH. Returning disability pensioners with back pain to work. Doktorgradsavhandling. Bergen: Universitetet i Bergen. 2007. Tilgjengelig på: https://bora.uib.no/handle/1956/2141
Introduction
Musculoskeletal complaints are one of the most common reason for short-term sick leave (1), and for sick leave lasting more than 2 weeks (2). One third of all disability pensions (DP) is due to disorders in the musculoskeletal system (2). Among disability pensioners, low back pain (LBP) is the most frequent condition (3), alone leading to 13-17% of all sick leave and DP (4). LBP has generally a benign course as most of those affected recover within a few weeks (5). However, some will develop chronic pain and disability which in turn may lead to absence from work and isolation from social life. Prolonged unemployment is associated with poorer physical and mental health (6-8) and lower life expectancy (9-12). For those individuals, LBP has serious impact on quality of life.

Long-term sick-leave, vocational rehabilitation and disability pensions due to back pain also represent an economical burden for the society. DP alone had a cost of more than 44 billion NOK, which is about 5.6 % of the Norwegian Gross Domestic Product (GPD) in 2004. There is an increasing concern in Norway as well as in other Western countries about the ever increasing number of disability pensioners falling out of work before the time of retirement (Figure 1).

In the years to come, a decreasing number of employees will have to carry the increasing expenses of the pensions, to a point where these costs will no longer be possible to fulfil after the year of 2050 (13). The government has through different initiatives tried to curb this development, so far with minimal effect. Steps have been taken to increase the age of retirement, which today is less than 60 years in average. It is also a goal to include a higher number of unemployed and disability pensioners in working life (13). The present doctoral thesis explores the possibility of including a higher number of disability pensioners in working life.

The Norwegian disability pension (DP)
In Norway, a DP can be granted if the work ability for any gainful work, or income for work, is permanently reduced by at least 50% because of disease, injury or inborn defect. All appropriate medical treatments and vocational rehabilitation should have been tried out (14). A new reform, a «time-limited DP», was introduced in 2004, meant for persons with a potential for returning to work after a limited period of time. These disability pensioners are scheduled to be re-examined after 1-4 years to evaluate if work ability has improved. Assessment of physical and mental functioning will be of great importance in these cases. Despite different initiatives to reach consensus concerning functional assessments, no standard procedure or criteria have been agreed upon for this evaluation (15).

Change in the Norwegian DP over time
In Norway, the incidence of DP started to increase in the early 1980s after a stable period in the 1970s (16, 17). The increase in DP stock occurred despite increased health and life expectancy in the population. The annual incidence of disability pensioners has fluctuated from around 20 000 in 1980 to 30000 in 2004, with a marked fall in 1993 (Figure 2). In 1991 a comprehensive benefit reform (stricter medical criteria, tougher regional and occupational mobility requirements) was passed, aiming to limit the access to DP. The inflow rate declined in the following years by as much as 20-30%, before a new increase took place from 1994-95 (16, 17).

The same pattern is reflected in the annual incidence of back pain disability pensioners (Figure 3). From 1989 until 1993 there was a marked decrease in the yearly inflow, but after 1993 the rate started to increase again. Thus, despite the fact that the legalisation is based on medical criteria, it is good reason to believe that other factors than disease, injury or inborn defect play a part in the granting of DP (18).

A strong relationship has been found between low socioeconomic status and incidence of DP (20, 21). Increasing unemployment has been used to explain the increase in DP in the late eighties (22, 23). However, a new increase in DP inflow took place a few years later even if the unemployment rate at that time was low. An increased number of individuals not returning to work after rehabilitation (24), a higher employment rate among women and the increased birth rate after the Second World War, may explain this increase (18). When the unemployment rate is low, as is presently the situation in Norway, the health related absence from work is likely to increase. Changes in social structure during the last 20 years with increased demands on educational levels, skills, productivity and mobility may also have lead to increased health-related exclusion from work (25).

In 2001, the Norwegian Government together with labour and employer organisations reached an agreement to make a joint effort to reduce sick leave, actively include individuals with disabilities into working life, and to increase the actual age of retirement (Including working life, 2001). Several economic incentives have been introduced in connection with this agreement.

Comparisons to other countries
Since the social insurance schemes in the Western countries are not identical, it is often difficult to compare statistical information (26, 27). Even between the Nordic countries the social insurance schemes differ (28). The number of disability pensioners in the Nordic countries is high compared to most other European countries (17, 26). Countries with high benefit levels tend to have high prevalence of disability pensioners. Recently, countries with lower benefit levels have had equally high rates of inflow, and the rates of outflow are also similar. Comparisons between countries do not support the impression that high or increasing unemployment rates lead to increased rates of disability pensioners (26). At the same time, there is some indication that a stricter access to disability benefits results in somewhat higher unemployment level. In most countries, the costs of disability benefit in percentage of GDP have increased from 1990 to 1999, although with considerable differences between countries (Table 1).

Compared to all other OECD countries, Norway has the highest expenditure in all disability-related programmes (Table 2). The steady increase in number of individuals receiving DP in general calls for vigorous efforts seeking to reverse this trend.

Low back pain (LBP)
According to the European Guidelines for prevention of low back pain (29), LBP is defined as pain and discomfort, localised below the costal margin and above the inferior gluteal folds, with or without leg pain, and is often divided into specific (10-20%) and non-specific (80-90%) LBP. Most back pain is non-specific (common), defined as pain not attributed to recognisable, known specific pathology (e.g. infection, tumour, osteoporosis, ankylosing spondylitis, fracture, inflammatory process, radicular syndrome or cauda equina syndrome). Acute back pain is usually considered self-limiting as 90% of cases tend to recover within 6 weeks, while 2-7% develop chronic pain (29). Physical problems are often considered as most important in the acute stage ( 12 weeks) with implications for the individual’s daily life, family and work (30).

Many factors seem to influence the development of disability in chronic back pain. A widespread musculoskeletal pain pattern, rather than a localized one, has been found to predict long-term work incapacity (31). Individuals who develop chronic pain and long-term disability often have other complaints as well (32-34). Sensitisation has been suggested to be the underlying mechanism for co-morbidity (35). Sensitisation is an increased reactivity to stimuli (pain) caused by repeated use. Increased sensitivity has been documented to be associated with chronic LBP (36) and fibromyalgia (37). Individuals at high risk for future DP due to back pain are likely to perceive their work as physically demanding, have lower education and feel tired and worn out (34).

Because disability related to chronic LBP is multicausal and complex, vocational rehabilitation should focus on different aspects, including the individuals’ reaction to pain, and on their worries of how the pain will affect their health and work. People with chronic pain often feel that the pain controls them (38). When encouraging disability pensioners to increase their activities of daily living and start taking part in work activities, it is important to teach them to understand how they can regain control over their own situation. They also need proper information and reassurance that pain is not dangerous.

Functioning and work ability
To explore the relationship between work-status and functioning of patients with chronic LBP, the International Classification of functioning, disability and health (ICF) can be useful (39).

International classification of functioning, disability and health (ICF)
The ICF consists of two parts. One part includes the components body structure and body function, activity and participation. These dimensions can be described according to functioning (positive aspects) and disability (negative aspects). The second part includes personal and environmental factors. Functioning and disability are conceived as a dynamic interaction with the personal and environmental factors in a health perspective (39).

Body function and structure. Body function is related to physiological and psychological functions of body systems, like functions of the respiratory system, functions of the joints and bones or mental functions, impairments are related to significant deviation or loss within these systems. Individuals with chronic LBP may have reduced physical fitness (40-46) and they may experience pain (47, 48). Disuse may result in deconditioning and deterioration of the musculoskeletal, cardiovascular, and central nervous systems and may also lead to obesity and depression (41, 49).

Activity. Activity is described as execution of a task or action by an individual, and activity limitations are the difficulties an individual may have in executing tasks or actions. Patients with chronic LBP may be limited in performing activities of daily living such as self-care, dressing or performing household tasks or in work-related activities, such as carrying, moving, and handling objects (50-54)).

Participation. Participation is described as involvement in life situations, the societal perspective of functioning. Participation restrictions are difficulties an individual may experience in involvement in life situations. Patients with chronic LBP may be restricted in sports activities or social life (48, 55, 56), or in participation at work (55, 57).

Environmental factors. Environmental factors refer to the physical, social and attitudinal factors making up the environment in which people live and conduct their lives. Examples of such factors are other people in different relationships and roles, attitudes and values, social systems and services, and policies, rules and laws. In patients with chronic LBP, marital status (58, 59), and social insurance litigation (60-62) may influence disability or functioning. The availability of modified work places, adjustment latitude, and rigidity of rules of employment, lack of suitable policies, downsizing and distance from the labour market are other factors which may influence disability or functioning in disability pensioners with LBP (63).

Personal factors. Personal factors refer to the particular background of an individual’s life and living. In patients with chronic LBP, age (64), gender (59, 65), educational level (21, 64, 66, 67), depression (68, 69), fear of movement (70, 71), self-efficacy (72, 73), coping (68, 74), pain cognition (75) and self-esteem (76) are personal factors which may influence disability and functioning.

Work ability
There is no definition, universally agreed upon, of basic requirements for work ability. The complex issue of work ability is addressed by organizations like WHO and EU as: «Individuals’ work ability is based on their physical, psychological and social capacity and professional competence, the work itself, the work environment, and the work organization» (77). Ilmarinen (78) state that factors that influence work ability make a complex relationship between environmental factors like work, values, competence, and health and social relations. Work ability probably determines whether people with longstanding health problems are able to return to work. Self-assessed work ability has been shown to predict return to work in patients on sick leave due to musculoskeletal pain (79-81). Work ability is determined by the individual health condition and by what is expected from work. Work ability is sometimes described in relation to the physical and mental demands of the job (82). Adjustment latitude is another way of describing work conditions and demands of the job (83) and is defined as opportunity to adjust work to health; for instance to do other tasks, work at a slower pace or having possibilities to take unscheduled breaks (84). When the adjustment latitude is high, it is more likely that a person regains ability to work (83, 84). Opportunities to adjust work to the health condition may be a prerequisite for disability pensioners with LBP to succeed in returning to work.

Barriers against returning to work
in disability pensioners
Disability pensioners with back pain face a number of problems if they consider a return to work (8, 85). They may have become progressively less fit through inactivity (40, 41), their vocational skills may be outdated because they have been out of work for years, suitable adjusted work may be difficult to find, there may be prejudice from employers and they may have problem of accessing vocational-rehabilitation programmes which are often designed for employed persons on sick leave (63). Recently, the Norwegian National Insurance Administration carried out a project, interviewing disability pensioners about the prospect of a return to work (86). Three risk factors for not returning to work were pointed out: worries about own future health, concerns about coping ability with working life, and economical concerns. Worries about own health was the most frequently reported reason for not being able to return to work. Among those who succeeded in returning, own motivation or having a «fighting spirit», and economic incentives were pointed out as important factors for success.

Prognostic factors for not returning
to work after sick leave
Previous studies concerning prognosis for not returning to work have pointed to a number of possible factors. They include psychological factors such as distress and fear avoidance beliefs (68, 70, 87, 88), personal aspects such as high level of pain (89-91) and work related factors such as low job satisfaction (69, 92, 93). Social and economical issues are also found to be of importance (68, 69, 94). In a systematic review by Steenstra et al. (59), specific LBP, higher disability levels, older age, female gender, more social dysfunction and isolation, heavier work and receiving higher compensation were identified as prognostic factors for longer duration of sick leave, while job satisfaction, a history of back pain and level of education did not seem to influence duration of sick leave. Thus, the factors found have been manyfaceted and consistent with the impression that chronic LBP is a multicausal phenomenon.

Main and Burton (95) stated that obstacles or barriers generally related to failure to return to work are associated with the person’s perceptions and concerns of health and work: demands at work, social support, self-perception of work ability (79, 80, 96), and fear avoidance beliefs and low expectations about return to work (8, 72, 97). Thus, rehabilitation efforts should pay close attention to the barriers of return to work as perceived by the disability pensioners themselves, and address these issues specifically in the vocational rehabilitation programmes.

Expectancy
Patient beliefs and expectations regarding recovery and return to work is found to be a very important prognostic factor for recovery and return to work (72, 73, 75, 98, 99). Positive expectancy of recovery is associated with better health outcomes in many different conditions including chronic pain (99). Worker recovery expectations have been found to influence time to return to work, as measured through suspension of time loss benefits (72, 100).

Bandura’s concept of self-efficacy (101) has been a common theoretical framework used to explain relationships between beliefs and outcome. Self-efficacy refers to an individuals belief in own ability to achieve a specific goal (75). The effect of expectancy can also be explained with the cognitive activation theory of stress (CATS) (35, 102). The challenge or stress facing an individual is evaluated based on the expectancies connected to the situation and to the possible acts available to the individual. These possible acts depend on previous experiences and learning. In CATS, learning is defined as acquisitioned stimulus expectancy or response outcome expectancy. Previous success produces positive response outcome expectancy, and lack of success produces expectancy of failure. Coping is defined as positive outcome expectancy. When the individual learns that there is no relationship between acts and results, this may lead to a feeling of helplessness. When the individual learns that the acts lead to failure, this leads to a feeling of hopelessness. Many disability pensioners have previous experiences of failure in their efforts of returning to work, and this may have lead to negative outcome expectancy and a feeling of hopelessness when considering a return to work. Theories of sensitization support this hypothesis (35). Disability pensioners with back pain probably have a long history of pain, and unpredictable and strong pain may have lead to learned helplessness and hopelessness (103), as their actions to alleviate the pain have been unsuccessful and unpredictable.

Fear avoidance beliefs
The fear avoidance model provides a cognitive behavioural framework when describing patients with high levels of pain-related fear and gives an explanation of the mechanism whereby back pain patients may develop persistent disability (104, 105). In this model catastrophic appraisal of the pain experience is emphasised, which in turn lead to fear and hypervigilance. Another implication is activity avoidance, largely caused by fear that activity will lead to injury and will exacerbate the pain problem (71). When patients have a catastrophic appraisal of their pain and believe that their pain signifies harm, it is expected that they would also have a negative outlook regarding recovery. This also fits into the theories of expectancy. Negative expectancy of recovery and a belief that activity may result in increased pain has been found to be strongly related (106).

There is evidence that anxious persons have a cognitive processing priority for information that is related to their fears (107). Anxious persons will detect fear-related information earlier than non-anxious persons. Persons suffering from medically unexplained somatic complaints, like chronic musculoskeletal complaints, spend a lot of time worrying over their condition.

Return to work in disability pensioners
Studies concerning return to work in disability pensioners with back pain have been scarce until now. An exception is the study of Watson et al. (63) where the effect of a vocational-oriented rehabilitation programme was investigated. Enrolled in their study were unemployed individuals who reported they were unable to access work because of LBP. The programme consisted of psychological, physiotherapeutic and vocational focusing for 12 half days over 6 weeks with up to 3 hours of additional individual vocational counselling. All parts of the programme exclusively focused on achieving and retaining employment. In this study, nearly 40% of those enrolled eventually became re-employed in the course of 6 weeks. However, the study did not include a control group, making general conclusions uncertain.

In 2003, NIA interviewed 23 000 disability pensioners about the prospect of a return to work (108). Of these, 10 300 (46%) expressed motivation for trying. However, the report did not give a specific account of the factual outcome, but concluded that the observation period had been to short to demonstrate cost-effectiveness.

Return to work in patients on sick
leave due to LBP
The chance of returning to work after sick leave due to LBP has been shown to steadily decrease over time, and is negligible after 1 year on sick leave (5, 64, 109). Once a DP is awarded, the likelihood of ever returning to work is almost zero. Within OECD, approximately 1% of the disability benefit stock leaves the rolls each year due to recovery or work resumption (26). Exceptions are United Kingdom and the Netherlands which have an outflow rate of 5% and 3 % respectively. The low rate of outflow is found in countries with a strong focus on avoiding inflow through vocational rehabilitation and training, like the Scandinavian countries, and in which it may be expected to be difficult to re-integrate those who are granted DP. The same tendency is seen in countries with strong focus on economic incentives to get benefit recipients off the rolls (26).

Vocational-oriented rehabilitation models
Traditionally, vocational rehabilitation models have focused on restoring the physical, mental and social functioning of patients to their previous condition after disease or injury (110). In this bio-medical model, pain is regarded as tissue injury which leads to impairments, disability and incapacity for work (111). It is assumed that when pain alleviates, disability will also disappear. However, the relation between severity of back pain and disability in daily activities and work has been found to be low (111). In another study, improvement in physical performance and pain was related to return to work at 1-year follow-up evaluation (90). Therefore, a more complex model is needed. Waddell and Burton (112) have suggested that rehabilitation programmes should include health-related, personal or psychological and social or occupational dimensions according to a bio-psychosocial model. In LBP disability pensioners, social issues may be of great importance. Waddell states that the society fails to make arrangements that enable disabled patients to utilize the retaining work potential, and therefore disability have become a political rather than a medical issue (111).

There is evidence that physical exercise and appropriate education are effective in secondary prevention of LBP (29), and that exercise also has an effect on sick leave, costs and new episodes of LBP in employees (113). There is also strong evidence that intensive bio-psychosocial rehabilitation with a functional restoration approach improves pain and function, while less intensive treatment does not show clinically relevant improvements (114). However, disability pensioners who have been out of work for years have probably gone through several previous treatment programmes that have failed to reduce pain and disability sufficiently. Because patients not returning to work often have increased co-morbidity and emotional distress (32-34), in addition to lower educational level, these factors must be taken into consideration in rehabilitation efforts. It may be important to teach the individual to manage the painful condition, and try to change how they think about the pain and their ability to work. There is evidence that cognitive intervention programmes and exercises improve function (115) and coping (116) in patients with chronic LBP (>1 year) considered for surgery. The cognitive intervention in these programmes consisted of lectures aiming to give the patient an understanding on how ordinary physical activity would not harm the back (reassurance) and a recommendation to use the back in a flexible way.

Both identification of obstacles against work, but also evaluation of expectancy for a return to work is of importance in vocational rehabilitation. Main and Burton (95) stated that obstacles against work depend on the person’s own perceptions and concerns about health and work. Motivation for re-employment may increase by addressing the perceived obstacles and focusing on the personal resources in the rehabilitation programme. Proper information, education and reassurance, and close co-operation with the social insurance and work offices may also be important to succeed in returning disability pensioners to work.

Summary of papers

Paper 1
This study shed light on the many barriers that disability pensioners with long-lasting back pain perceive as obstacles for a return to work by using focus group interviews. Many of the participants pointed to conditions at their former work places that they believed contributed to the disability process, and which would make it difficult to return to work. Factors mentioned were a high demand for efficacy and productivity and hostile attitudes from superiors and colleagues. Poor self-judgement of work ability due to poor health was considered by many to be an important obstacle. Some also expressed a general lack of self-esteem and a pessimistic view of the future. Lack of support from officials and lack of modified work places were mentioned as contributing factors for not being able to return to work. Finally, insufficient economical incentives were mentioned as a de-motivating factor. Possible solutions to these barriers included flexible job possibilities, secure and incentive economic arrangements, and an understanding and supportive attitude from all parts involved in the return to work process.

Paper 2
The second paper aimed to discuss the physical and mental functioning, and to explore potential characteristics which could describe those who had a negative expectancy for work. Standardised and validated questionnaires and physical performance tests were used to measure physical and mental functioning in a cross sectional design. Substantial disability was demonstrated by all self-report and performance measures. Nearly all participants reported high levels of pain and other health complaints, and self-reported working ability was rated as low. However, a subgroup with less complaints and a more positive attitude towards work were identified: fifteen (18%) of the participants believed that they could return to work eventually. This subgroup of disability pensioners was characterised by having better physical performance and less fear avoidance for physical activities. Poor physical performance was related to not believing in a return to work. This was particularly pronounced for dynamic flexibility of the trunk, neck and shoulder flexibility, perceived problems with work-related function and high fear avoidance of physical activities.

Paper 3
Paper 3 evaluated the effect of a brief vocational-oriented intervention in a randomised controlled design. The intervention had no statistically significant effect on return to work as only 2 participants in each group had a reduction in disability payment at 1 year follow-up. However, 10 participants (22%) in the intervention group and 5 (11%) of the controls reported to have entered a return to work process after 1 year. Even if the result did not reach statistical significance, the intervention may still be of practical and economical significance since the difference between the groups gave an Absolute Risk Reduction of 11 and the number needed to treat (NNT) was 9.

Several potential predictors for having entered a return to work process were identified. The pensioners who had a positive expectancy, less pain and better physical performance were more likely to having entered a return to work process during the following year.

Conlusions
l The disability pensioners themselves perceived that earlier negative experiences in their work life, low self-judgement of working ability, low self-esteem and organizational and economic conditions of the disability process were barriers against work.
l Considerable physical limitation, emotional distress, pain and reduced health in general were demonstrated in this group of disability pensioners. A minority believed that they could return to work eventually. Lack of belief was related to poor physical and work-related function, and to high levels of fear avoidance for physical activities.
l The brief vocational-oriented intervention did not have a statistically significant effect on return to work or having entered into a process of return to work. However, twice as many in the intervention group reported to have entered a process of return to work compared to the controls. These individuals were characterised by a more positive attitude towards work, less physical limitations, less pain and less fear avoidance beliefs.
l This thesis supports previous suggestions that returning disability pensioners to work is, in general, a difficult task. However, the vocational intervention offered in this study might still be cost-effective if carefully selecting participants most likely to succeed.

References

Magnussen LH. Returning disability pensioners with back pain to work. Doktorgradsavhandling. Bergen: Universitetet i Bergen. 2007.
Tilgjengelig på: https://bora.uib.no/handle/1956/2141

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