Does shift work cause adverse health effects and how should companies respond?

There is growing evidence that working antisocial hours impacts the health and wellbeing of employees. With millions of workers regularly doing shift work, employers should take note of guidance on how to mitigate and monitor this risk, Michelle Penn of BLM explains. And with the precedent for compensation already set in Denmark, risk managers shouldn’t take a ‘wait and see’ approach.

Since the International Agency for Research on Cancer (IARC) concluded in 2007 that working nightshifts is “probably carcinogenic to humans”, the impact of antisocial working hours on health has garnered growing attention.  

Since then the Trade Union Congress (TUC) has investigated this issue, claiming that various studies show “that shift work is now the second biggest cause of work-related cancer deaths after asbestos.”

Furthermore, the precedent for legal claims has already been set. In 2008 in Denmark, where occupational illness claims are dealt with by a no-fault workers’ compensation scheme, the government started compensating women who developed breast cancer after working nightshifts, even though a Danish study conducted at the initiative of the National Board of Industrial Injuries in Denmark concluded that there was “limited evidence of a causal association between night shift work and breast cancer.”

The evidence

There is a growing body of research that highlights a link between shift work and ill health. Data released by UK government agency Health and Safety Executive (HSE) in October 2014 indicated a link between shift work and over 500 deaths from breast cancer. Meanwhile, a separate study of nurses concluded that night shift work “may contribute to an adverse chronic disease risk profile and that risk factors may vary depending on the age at which night shift work was performed.” 

Cancer Research UK has noted that some studies have raised concerns that working in shifts or being exposed to light at night could increase the risk of cancer, particularly breast cancer. The charity states that “for now, the evidence is not completely certain” but advises that female shift workers should take sensible measures such as reduced alcohol intake and regular health checks.

Behavioural factors linked to shift work might also have an effect, such as increased alcohol intake, little exercise or different eating patterns. It is also suggested that shift workers may take sleeping pills more frequently.

Links are also being drawn between shift work, obesity and diabetes. Poulsen et al (2014) found that in the occupational setting, obesity was associated with shift work, possibly because of the difficulties in maintaining a healthy lifestyle, and that obesity was the strongest risk factor for developing diabetes.

Another study by Huth et al (2014) investigating the relationship between job strain and type two diabetes mellitus (T2DM) concluded that those who experience high job strain are at higher risk for developing T2DM independently of traditional risk factors.  Indeed, “long working hours can be toxic”, according to an article in The Lancet in September, after a study found a link between working 55 hours or more per week and type two diabetes, but only in individuals in “low socioeconomic status groups.”

Advice for companies

With around 3.6 million people in the UK doing shift work “most of the time,” how should companies be responding?

Guidance from the HSE notes that shift work may result in: disruption of the internal body clock (circadian rhythm); fatigue; sleeping difficulties; disturbed appetite and digestion; reliance on sedatives and/or stimulants; and social and domestic problems. All of these can in turn affect performance, increase the likelihood of errors and accidents at work and might have a negative effect on health.

The HSE guidance aims to improve understanding of shift work and its impact on health and safety by providing advice on risk assessments, design of shift-work schedules and the shift-work environment.  It suggests measures that employers, safety representatives and employees can use to reduce the negative impact of shift work and reducing tiredness, poor performance and accidents by enabling employers to control, manage and monitor the risks of shift work.

Shift work is necessary in a huge range of employments but, as highlighted by the HSE guidance, there are practical steps which can be taken to reduce the potential risk. Given the growing body of research into this subject, a “do nothing/wait and see” approach by employers is no longer appropriate.

Will there be claims in the future?

The HSE has commissioned the University of Oxford to undertake an extensive study on the relationship between shift work and chronic disease, with a focus on shift working patterns in relation to cancer and other chronic conditions. The study is scheduled to be completed by December 2015, and employers and risk managers would do well to watch closely. Let’s see how the TUC interpret the findings and whether this is the report that will trigger claims being made in the future.

Michelle Penn is a partner at BLM (michelle.penn@blmlaw.com)

Michelle Penn - BLM