Effects of sleep changes on pain-related health outcomes in the general population: A systematic review of longitudinal studies with exploratory meta-analysis

Abstract

Emerging longitudinal research has highlighted poor sleep as a risk factor of a range of adverse health outcomes, including disabling pain conditions. In establishing the causal role of sleep in pain, it remains to be clarified whether sleep deterioration over time is a driver of pain and whether sleep improvement can mitigate pain-related outcomes. A systematic literature search was performed using PubMed MEDLINE, Ovid EMBASE, and Proquest PsycINFO, to identify 16 longitudinal studies involving 61,000 participants. The studies evaluated the effect of sleep changes (simulating sleep deterioration, sleep stability, and sleep improvement) on subsequent pain-related outcomes in the general population. A decline in sleep quality and sleep quantity was associated with a two- to three-fold increase in risk of developing a pain condition, small elevations in levels of inflammatory markers, and a decline in self-reported physical health status. An exploratory meta-analysis further revealed that deterioration in sleep was associated with worse self-reported physical functioning (medium effect size), whilst improvement in sleep was associated with better physical functioning (small effect size). The review consolidates evidence that changes in sleep are prospectively associated with pain-related outcomes and highlights the need for further longitudinal investigations on the long-term impact of sleep improvements.

Keywords: Health; Longitudinal; Meta-analysis; Pain; Prospective; Public health; Sleep; Systematic review.

Fig. 1

Summary of the framework underlying this systematic review and methodological design of the included studies. Based on the experimental and epidemiological evidence, the figure illustrates the potential prospective relationship between changes in sleep and chronic pain experience. Changes in sleep from baseline to follow-up represents the variable predicting subsequent chronic pain experience. Change in sleep* refers to change in i) sleep duration, ii) sleep quality, and/ or iii) insomnia symptoms. Pain-related health outcomes^# represents the factors that make up overall pain experience, namely, the risk of developing a pain condition, changes in physiological inflammatory and immune processes and changes in self-reported pain-related health and functioning status.

Fig. 2

Flowchart of study selection.

Fig. 3

Risk of bias checklist and rating adapted from STROBE guidelines for reporting observational epidemiological studies and modified AHRQ quality assessment criteria for observational studies. AHRQ: agency for healthcare research and quality, STROBE: strengthening the reporting of observational studies in epidemiology.

Fig. 4

Comparison of PCS and SF-36 bodily pain scores from baseline to follow-up for different sleep change trajectories (Lower scores on the PCS and bodily pain subsection indicates greater physical health limitations and pain related interference and disability).

Fig. 5

Forest plots summarising the effects of changes in sleep on PCS scores at follow-up. Lower PCS scores represent poorer physical functioning. a) Compares individuals who were ‘persistent poor sleepers’ with those who were ‘persistent good sleepers’ over time. b) Compares individuals who developed sleep disturbances over time (‘new poor sleepers’) with those who were ‘persistent good sleepers’ (i.e. evaluating the effect of negative sleep deterioration). c) Compares individuals whose sleep disturbances remitted over time (‘remitted poor sleepers’) with those who were ‘persistent poor sleepers’ (i.e. evaluating the effect of positive sleep improvement).