Gill Weston, researcher and consultant on work-related wellbeing, shares research from her recent study on the differences between the sleep quality and quantity of people with atypical work patterns and people with typical 9-to-5 Monday-to-Friday type work patterns. The research was conducted as part of Gill’s PhD at the ESRC International Centre for Lifecourse Studies within the UCL Institute of Epidemiology and Health Care.
How much sleep do working adults need?
Individual sleep needs vary, but generally, adults aged up to 64 years are recommended to sleep at least seven hours per night, fall asleep within about 30 minutes, wake for no more than five minutes once per night, and feel satisfied with their sleep. Yet poor sleep, such as sleeping for less than 7 hours per night, and difficulties with initiating and/or maintaining sleep is common, particularly on workdays.
Habitually poor sleep has been linked to chronic diseases, mental and cognitive health problems, and work-related injuries. It’s also been linked to productivity losses; indeed the economic toll of poor sleep in the UK is estimated at over £40 billion annually.
What are atypical work patterns?
Atypical work patterns are those work schedules that extend beyond the traditional 9-5 Monday-Friday framework. They include working more or less than the standard 35-40 hour week, as well as weekend working, and nonstandard schedules such as early mornings, evenings, nights and rotating shifts. They are characteristic of the modern economy due to 24/7 operating systems and fluctuating demands for goods and services.
Labour market statistics for the UK estimate that approximately 40% of women and 12% of men work fewer than 30 hours per week, a quarter of men and 10% of women work more than 45 hours per week. They also estimate that 31% workers work weekends, 37% work evenings, 16% work at night, and 20% work shifts. Although some workers combine these patterns, data on how many do so is scarce.
Why was this study needed?
As sleep is a cornerstone of health and wellbeing, we were curious to know if it might be compromised by atypical work patterns. Whilst we found some research which suggested that nightshifts and long working hours were associated with insufficient or poor quality sleep, few studies investigated the effects of other atypical work patterns, and these rarely accounted for people combining atypical work patterns. The studies mostly utilized data from workers living in East Asia and Scandinavia – regions which differ contextually to the UK due to labour market norms, welfare state provision, and legislative protection (i.e., factors which may impact the outcomes for workers). Additionally, the studies tended to focus on particular work settings, such as the public sector, or on white-collar workers; and many of the studies omitted women.
To address some of these gaps, our study aimed to investigate the associations between a wide range of atypical work patterns and sleep. We wanted to look at both sleep quality and sleep quantity, with the latter measured in terms of both insufficient sleep and sleeping longer than the recommended amount. To ensure that our study would be representative of the whole UK workforce, we wanted to include all types of workers and women, and to account for combinations of different work patterns.
Which data and methods were used?
We used data from Understanding Society, the UK Household Longitudinal Study (UKHLS), accessed via the UK Data Service. This data set, which has been following the lives of thousands of people across the UK since 2009, enabled us to investigate the work patterns and sleep experiences of over 25,000 men and women, diverse in age and occupation between 2012 and 2017. The data provided us with a robust representation of the UK workforce, with workers answering a host of questions, including about their jobs, their hours of work, their work schedules, their health, and their sleep.
We focused on three types of atypical work patterns representing the hours and the schedules people work:
1) part-time (fewer than 35 hours per week) and extended weekly work hours (41-54 hours, and 55 hours or more) compared to the standard 35-40 hour working week
2) weekend working (sometimes and frequently) compared to weekday working
3) nonstandard schedules (e.g. shifts, early mornings & late evenings) compared to non-shift, day-time schedules.
We used this data to assess the prevalence of the different work and sleep patterns, and then to estimate regression models each for sleep duration and for sleep disturbance, adjusting for combinations of atypical work patterns, and individual-level factors such as age, caring responsibilities, income, health, job satisfaction, and other conditions that could impact sleep.
What we found
Our results showed nearly a third of participants worked part-time, and more than a third worked extended hours, almost 60% worked weekends, and more than a quarter worked nonstandard schedules. Around half combined two or more atypical work patterns. Two-fifths experienced short sleep (less than 7 hours/night), fewer than 4% experienced long sleep (more than 9 hours/night), and a quarter experienced sleep disturbance (e.g. struggling to fall asleep within half an hour, waking up in the middle of the night or early morning, and a self-rating of poor quality sleep).
We found a clear association between atypical work patterns and poor sleep, with extended weekly work hours, weekend working, and nonstandard schedules all linked to short sleep durations. Nonstandard schedules and frequent weekend working were also associated with long sleep durations, as was working part-time. All the atypical work patterns were linked with increased sleep disturbance.
Supplementary testing indicated that workers with two or more atypical work patterns experienced the poorest sleep.
Further analyses suggested some gender differences in the impact of working hours on sleep, with women showing a stronger association between extended weekly work hours and short sleep duration, and men showing a stronger association between part-time weekly work hours and longer sleep durations.
What are the implications of our findings?
In a fast-paced world where atypical work patterns are increasingly the norm, the importance of sleep for worker health, productivity, and the economy, cannot be overstated. Our research should be a wake-up call to employers and policymakers to better support workers. They should ensure sufficient rest and recovery are prioritized together with a careful consideration of the impact of the timing and scheduling of work for worker optimal health and productivity.
Scheduling appropriate break periods, encouraging workers to disengage from work outside their normal working hours, minimizing overtime cultures, aligning individuals’ chronotypes (e.g. ‘larks’/early birds who prefer to wake early and do activities early in the day; and ‘night owls/evening types’ who prefer to wake later and do their activities later in the day) with their work schedules, and involving workers in setting their shift rotations are crucial steps in supporting workers. It’s also important that employers tackle the psychosocial stressors (such as high job demands and low autonomy) that contribute to poor sleep patterns, and that they compensate employees for the negative consequences of working long and irregular hours.
The research presented in this blog is based on Gill’s recent publication which can be viewed online. This work was co-authored by Afshin Zilanawala, Elizabeth Webb, Livia Carvalho and Anne McMunn.
About the author
Gill Weston is a researcher and consultant on work-related wellbeing. Her research focuses on work-related determinants of mental health, mental wellbeing, and sleep. Her consultancy focuses on work-related stress, work-engagement, and happiness at work. She obtained her PhD in Epidemiology and Public Health from University College London (UCL Institute of Epidemiology and Health Care) having used data from the UK Household Longitudinal Study, Understanding Society, to study atypical work patterns and their associations with psychological wellbeing and sleep.