Night-shift work is associated with increased pain perception

Abstract

Night-shift work is associated with increased pain perception by Matre D, Knardahl S, Nilsen KB To the authors' knowledge, pain sensitivity after night shifts has never been investigated. The present findings indicate that pain sensitivity does increase for some types of pain stimuli. Furthermore, the results indicate that experimental sleep restriction studies are relevant in assessments of health complaints among shift workers. Original article Scand J Work Environ Health. 2017;43(3):260-268. doi:10.5271/sjweh.3627 Night-shift work is associated with increased pain perception Objectives The aim of the present study was to determine whether shift workers exhibit increased perception of experimentally induced pain after working night shifts. Affiliation MethodsThe study was a paired cross-over design with two sleep conditions, after at least two nights of habitual sleep and after two consecutive night shifts at work. Fifty-three nurses in rotating shift work participated. The sensitivity to electrically induced pain, heat pain, cold pain, pressure pain and pain inhibition was determined experimentally in each sleep condition. Sleepiness and vigilance were also assessed.Results Night-shift work (NSW) increased the sensitivity to electrically induced pain and heat pain (P≤0.001).Relative to habitual sleep, electrically induced pain increased by 22.3% and heat pain increased by 26.5%. The sensitivity to cold and pressure pain did not change, changes relative to habitual sleep was <5% (P>0.5). Pain inhibition was 66.9% stronger after NSW versus after habitual sleep (P<0.001). Sleepiness (measured with the Karolinska Sleepiness Scale) increased from 4.1 after habitual sleep to 6.9 after NSW (P<0.001). Vigilance decreased after NSW, measured as a 0.03-second decrease in reaction time (P<0.005).Conclusions Changes in pain sensitivity after NSW is measurable with clinically relevant effect sizes and may be an important marker for studies comparing the physiological effects of different shift work schedules. Explanations for the differential effect on different pain modalities should be a focus for future studies.

Prevalence of musculoskeletal symptoms among industrial employees in a modern industrial region in Beijing, China

“…Therefore, building a cooperative relationship between industrial enterprises and relevant medical institutions, or the provision of on-site occupational health care services is an important consideration in the reduction of MSDs. Our study was consistent with early studies in that a number of factors are associated with MSDs, including female gender, [39,40] increased age, increased BMI, [41] smoking, [42] concurrent chronic diseases, [43] graveyard shift, [44,45] and increased job tenure. [7,13] Furthermore, there are some potential factors were not investigated in this study.…”

Sleep restriction does not potentiate nocebo‐induced changes in pain and cortical potentials

“…After night work, compared to after habitual sleep, subjective pain scores increased by 19% (mean difference 0.4 cm). This effect size was comparable to other studies on heat pain (26.5% increase) based on data from the same individuals (Matre et al, ) and another study on cold pain after night work (28% increase) (Pieh et al, ). Similar studies using experimental sleep restriction have shown comparable effect sizes (Azevedo et al, ; Matre, Andersen, Knardahl, & Nilsen, ; Matre, Hu, et al, ; Schuh‐Hofer et al, ; Tiede et al, ).…”

“…After night work, compared to after habitual sleep, subjective pain scores increased by 19% (mean difference 0.4 cm). This effect size was comparable to other studies on heat pain (26.5% increase) based on data from the same individuals (Matre et al, 2017) and another study on cold pain after night work (28% increase) (Pieh et al, 2018) Nilsen, 2016;Matre, Hu, et al, 2015;Schuh-Hofer et al, 2015;Tiede et al, 2010). Subjective pain scores increased by 20% (mean difference 0.30 cm) in the nocebo versus control conditions.…”

“…In the NSW condition, the subjects came directly to the laboratory from work. The protocol consisted of assessing responses to several pain stimuli, of which data on pressure pain, thermal pain, electrical pain and pain inhibition have been previously published (Matre, Knardahl, & Nilsen, ). The novel data in the present study were the inclusion of nocebo and the assessment of event‐related potentials.…”

“…Only the results from the electrical pain stimuli with nocebo expectations were analysed in the present manuscript. The results from the pressure pain, thermal pain and electrical stimuli without nocebo expectations were published in Matre et al ().…”