Work-relevant MSDs and the older workforce

Organisations must ensure that they are able to provide a healthy and productive environment for older workers, says Kathy Lewis.

When does old age begin? At what age does an individual become too old to carry on their current job tasks due to negative ageing effects on their neuromusculoskeletal system? In 44 BC, Cicero, the Roman philosopher and statesman, declared that you must not confuse old age with illness and went on to proclaim the many virtues of increasing age.

The concept of “successful ageing” has been discussed for several decades (Havighurst, 1963; Palmore, 1979; Williams, Wirths, 1965). So why is it that ageing itself and the impact on organisations of employing an ageing work­force often get a bad press?

The topic of ageing populations is increasingly researched and publicised. This is not surprising considering that, at present, a little more than 20% of workers in developed nations are aged over 60. It is predicted that this figure will rise to around 33% by 2050 (United Nations Publications, 2007).

In the UK, it is predicted that one-third of the population will be over 60 years of age by 2033 (Office for National Statistics). This change, due to lower birth rates and people living longer, results in a reduction in the economically active population (Crawford, 2011). It will have a major impact on society and the economy in general, and will place challenges on occupational health professionals and employers alike, in sustaining a healthy and productive ageing working population.

There is a growing tendency to challenge what it means to be an older worker. An emerging principle of maintaining ability, developing potential and continued competence, rather than focusing on age per se, is taking place (Ross 2010). This complements the “life course approach” discussed by Crawford (2011), which observes that we are ageing from the time we are born until the time we die and the general message engendered by Black (2008) of “think capability, not incapacity”.






quotemarksIn the UK, it is predicted that one-third of the population will be over 60 years of age by 2033.”



Since the introduction of the Equality Act 2010, the removal of the default retirement age will allow an individual to be assessed on whether or not they are able to cope with the demands of their work. This change in legislation complements our current understanding that a large variation exists regarding the effects of ageing on an individual (Crawford, 2011) and allows a decision to be made at an individual level on whether or not an employee is fit to continue working after a certain age.

Other government initiatives support the participation of people in the workforce, such as “Health, Work and Well-being”, a cross-governmental scheme promoting the benefits of work to health (Ross, 2010).

Work-relevant MSDs and the ageing process

Work-relevant musculoskeletal disorders (WRMSDs) are multifactorial and are influenced by a large number of individual, psychosocial and physical factors. Is it, therefore, possible to predict or understand what impact the ageing process may have on WRMSDs? This article will consider the positive and negative impacts of employing an older worker and highlight how an organisation can help support the ageing population to help sustain a productive and healthy workforce with regards to neuromusculoskeletal health.

The main physiological impacts of increasing age on our neuromusculoskeletal systems are discussed in detail below.

Soft tissue structures

As we age, muscle fibres shrink and lose mass (known as sarcopenia), which mainly affects the white fibres. The actual number of muscle fibres (mainly red fibres) decreases. Such gross muscle atrophy is the primary (non-pathological) change caused by ageing (Payton and Poland, 1983). This leads to a reduction in overall strength, which may affect an individual’s ability to undertake strenuous manual-handling tasks and may also adversely affect a person’s posture and result in longer reaction times.

In addition, the water content of tendons, ligaments and cartilage decreases with age. These soft tissue structures become stiffer and less able to tolerate stress and will make cartilage more susceptible to degeneration, which in turn may lead to osteoarthritis.

Heart muscles become less able to propel large quantities of blood quickly around the body, so an older person is likely to tire more quickly and take longer to recover. The body’s metabolic rate also slows, which can lead to obesity, which again has a negative impact on neuromusculoskeletal health.

Bone and joints

As a person ages, the balance between bone absorption and bone formation changes, ultimately resulting in a loss of bone tissue. This is largely due to the mineral content of bones decreasing, making them less dense and more fragile. This may result in osteoporotic changes, making an individual more prone to poor posture, to crush fractures of the vertebrae and to fractures throughout the body.

The main effects on joints of ageing are a reduction in flexibility and reduced “cushioning” from cartilage, which may lead to inflammation and pain. Ultimately, these changes are likely to have a detrimental impact on an individual’s ability to undertake physical work tasks. For example, reduced strength and joint mobility will adversely affect the ability to perform strenuous manual handling tasks.

Obesity and pain will further reduce function. Multi-site pain is an important risk factor for reduced work ability (Miranda et al, 2009). All of these factors may predispose an individual to adverse postural changes, which in turn create more loading on the neuromusculoskeletal system.






quotemarksWork-relevant MSDs are multifactorial and are influenced by a large number of individual, psychosocial and physical factors.”



Due to the complexity of issues such as occupational risk factors, lifestyle and genetics, it is difficult to determine at what age an individual’s physiological decline may be due to age. Despite this, Raven and Mitchell (1980) indicate that, on average, strength begins to decline at around the age of 40.

Physical capacity

Current supporting evidence, from “Crawford 2011: systemic review of literature”, found that moderate evidence was provided by generally consistent findings in few, small or low-quality scientific studies that ageing results in:




  • a reduction in aerobic capacity at a rate of approximately 10% for each decade;
  • an increase in weight;
  • a reduction in stature;
  • an increase in BMI; and
  • a reduction in muscle strength.

These factors can be mediated by maintaining high levels of physical activity (Crawford, 2011).

Balance mechanisms

It is more difficult to maintain balance as a person ages due to changes in balance receptors (Harper and Marcuss, 2006) and due to other common deficits that occur with age such as reduced visual abilities, pain syndromes and potential lack of joint proprioception – the sense of the relative position of neighbouring parts of the body – associated with this.

An individual will therefore be more prone to slips, trips and falls, which may cause a traumatic musculoskeletal complaint or cause an existing complaint to be aggravated.

Psychological and cognitive functioning

Depression is most common in elderly population groups (Harper and Marcuss, 2006). The main manifestations of depression, such as a reduced interest in activities and hobbies and general low mood, will have negative consequences on the neuromusculoskeletal health of an elderly person.

Age-relevant cognitive decline (ARCD) includes:




  • working memory loss;
  • processing problems;
  • encoding problems (putting information into memory);
  • retrieval (finding information in memory); and
  • reduced attention and concentration span (Harper and Marcus, 2006).

ARCD may adversely affect an employee’s ability to undertake effective “risk assessment” or recall correct procedures in the workplace, thus predisposing them to injury from undertaking poor manual-handling techniques when undertaking work tasks.

This must be balanced against the positive impacts of ageing, such as increased experience and knowledge that may help to negate other unfavourable effects.

Psychological changes

Again, “Crawford 2011: systemic review of literature” found that moderate evidence was provided by generally consistent findings in few, small or low-quality scientific studies of:




  • a reduction in reaction time due to increased central processing time;
  • an increase in caution;
  • an increase in accumulated knowledge and experience; and
  • cognitive abilities that are affected by numerous external and internal factors.

Influential factors

There are complex interactions involved in the factors influencing the neuromusculoskeletal health of an ageing worker. It can be seen that physical and psychological factors play an important role in the ageing process at an individual level.

Figure 1 creates a schematic representation of additional factors that must be considered when assessing the suitability of current work demands for an ageing employee. Such a model may also be used to help highlight where a “mismatch” may be present and to help prioritise resources.






quotemarksFactors influencing WRMSDs in the older workforce are numerous and complex. An increasing understanding of this is emerging.”



The starting point for neuromusculoskeletal fitness for each individual will be different, as will their course across the model. Good occupational health assessment and evaluation will help gain an insight into the individual’s current state of neuromusculoskeletal health.

Likewise, occupational health practitioners or line managers can use interview techniques with the worker to identify the potential positive impacts. By plotting a path across the model, thought must be given to how these factors influence the neuromusculoskeletal health of the ageing worker.

Other assessment of employee fitness for work of older workers

The work ability index (WAI) was developed by Tuomi et al (1996) in Finland. It is an instrument used in clinical occupational health and research to assess work ability during health examinations and workplace surveys.

It measures and records the work ability of employees and can be used at an individual, group or organisational level. The index is determined on the basis of the answers to a series of questions that take into consideration the demands of work, the worker’s health status and resources. It can be used to predict work ability in the near future.

Recent results of a 28-year prospective study show that perceived poor WAI scores undertaken in midlife are associated with accelerated deterioration in health and functioning, and can be used reliably as a predictor of health almost three decades later (von Bonsdorff et al, 2011). Such inferences mean that midlife WAI scores can be used as an early predictor of functioning in old age.

Scores obtained from the WAI can be used to prioritise interventions aimed at improving the employee’s work ability.

Table 1 below shows how the WAI is scored and the corresponding action levels.

Table 1: Work ability index scoring system























Result Category Work ability action

2-27


Poor


Reinstate work ability


28-36


Medium


Improve work ability


37-43


Good


Support work ability


44-49


Very good


Maintain work ability



While the WAI assesses more health issues than those affecting neuromusculoskeletal health, it is deemed a suitable tool for assessment, particularly in older workers, who are most likely to have coexisting pathologies that are likely to be influencing neuromusculoskeletal health.

Best practice for age management of WRMSDs

A good understanding of the causation and complexity of WRMSDs in the older worker is essential. Occupational health and safety professionals are encouraged to:

1. Assess the determinants of work ability of the older worker.

2. Target available resources to identified problem areas. This maybe aimed at an individual, group or organisational level and may include:




  • examination of job demands versus individual capabilities;
  • examination of work-rest scheduling;
  • shift-work guidance;
  • examination of current reporting systems;
  • provide health promotion, in particular, the importance of maintenance of physical activity;
  • training on age management to HR professionals, occupational health and safety practitioners and the older worker;
  • evaluation of job design; and
  • examination of organisational culture and worker beliefs (Buckle et al, 2008; Crawford, 2011; van den Berg et al, 2008).

3. Consider policy implications with regards to the neuromusculoskeletal health of the older worker, such as:




  • age strategy; and
  • the prevention of age discrimination in the workplace.

Positive effects of good age management can be seen in figure 2.

Conclusion and further research to consider

Factors influencing WRMSDs in the older workforce are numerous and complex. An increasing understanding of this is emerging.

Due to a rapidly increasing ageing population, more research is required on WRMSDs in this demographic group. Occupational health, safety, human factors (or human science, a multidisciplinary field incorporating contributions from psychology, engineering, industrial design, statistics, operations research and anthropometry), HR and general management professionals all have a role to play in the identification and management of neuromusculoskeletal health in the ageing worker.

Current UK legislation and government initiatives are likely to have a positive effect on enabling older workers to remain at work for longer, if the workers wish to do so.

Kathy Lewis MSc (health ergonomics) MCSP (chartered physiotherapist) is the director of Working-Health Physiotherapy and Ergonomics. She works across public and private sector organisations undertaking occupational health clinics and ergonomic projects. She also runs her own physiotherapy and sports-injury clinic, based in Guildford, Surrey, and teaches on ACPOHE DSE courses. She wishes to thank Professor Peter Buckle for his help in writing this article.

References

Black C (2008). “Working for a healthier tomorrow”. TSO, Norwich.

Buckle P, Woods V, Oztog O, Stubbs D (2008). “Workplace design for the older worker: strategic promotion of ageing research capacity”. University of Surrey.

Crawford J (2011). “The ergonomic challenges of an ageing workforce: managing the physical and mental workload”. Institute of Occupational Medicine, Edinburgh.

Cicero MT (44 BC) cited by Baltes P, Baltes MM, (eds) (1993). “Successful ageing”. Press Syndicate of the University of Cambridge, Canada, pp.1-2.

Havighurst RJ (1963) cited by Baltes PB, Baltes MM, (eds) (1993). “Successful ageing”. Press Syndicate of the University of Cambridge, Canada, pp.1-2.

Palmore E (1979) cited by Baltes PB, Baltes MM (eds) (1993). “Successful ageing”. Press Syndicate of the University of Cambridge, Canada pp.1-2.

Williams D, Wirths C (1965) cited by Baltes PB, Baltes MM, (eds) (1993). “Successful ageing”. Press Syndicate of the University of Cambridge, Canada pp.1-2.

Harper S, Marcus S (2006). “Age-relevant capacity decline: a review of some workplace implications”. Ageing Horizons, 5, pp.20-30.

Miranda H, Kaila-Kangas L, Heliovaara M, Leino-Arjas P, Haukka E, Liira J, Viikari-Juntura E (2009). “Musculoskeletal pain at multiple sites and its effects on work ability in a general working population”. Occupational and Environmental Medicine, 67 (7) pp.449-455.

Office for National Statistics.

Payton OD, Poland JL (1983). “Ageing process: Implications for clinical practice”. Physical Therapy, 63 (1) pp.41-48.

Raven PB, Mitchell J (1980). “The effects of ageing on the cardiovascular response to dynamic and static exercise”. In Weisfelt ML (eds) “The ageing heart”, New York, Raven Press, pp.269-289.

Ross D (2010). “Ageing and work: an overview”. Occupational Medicine, 60 pp.169-171.

Tuomi K, Ilmarinen J, Jahkola A, Katajarinne L, Tulkki A (1996) cited by Tuomi (2003).

United Nations Publications. World Population Ageing (2007).

Elders LA, van den Berg TI, de Zwart BC, Burdorf A (2008). “The effects of work-relevant and individual factors on the work ability index: a systematic review”. Occupational and Environmental Medicine, 66 pp.211-220.

Seitsamo J, Ilmarinen J, Nygard C, von Bonsdorff ME, Rantanen T (2011). “Work ability in midlife as a predictor of mortality and disability in later life: a 28-year prospective follow-up study”. Canadian Medical Association Journal. Early release published at www.cmaj.ca on 31 January 2011.

Comments are closed.