Background & Aims

Pain is a global public health problem, given its high prevalence and incidence, long duration, and social and economic impact.1,2 Socioeconomic inequalities in pain have been reported previously, which represents one potential target for prevention action.3 The mechanisms by which socioeconomic disadvantage contributes to pain remain uncertain. It has been proposed that low SEP can impact health via different pathways, including psychological and behavioral. Regarding the psychological pathway, sleep may play a role.4 To date, the only two studies that have evaluated the mediating impact of sleep on socioeconomic inequalities in pain as assessed by neighborhood SEP reported mixed results.5,6 So, the mediating role of sleep on individual-based SEP inequalities in pain remains unknown. Given the limited evidence and mixed results, we explored the potential mediating effect of sleep quality and duration on the association between SEP and pain.

Methods

We analyzed data from 1719 individuals [52.0% women; mean age (SD) = 60.1 (9.1) years] from the first (2009-2012) and second (2014-2017) follow-up phases of the CoLaus|PsyCoLaus study in Lausanne, Switzerland. Occupational position of both the father and individual, educational level, and income were considered as socioeconomic indicators. Self-reported sleep quality and duration— potential mediators—were based on the Pittsburgh Sleep Quality Index (PSQI – ranged from 0 to 21; high score values represent poorer sleep quality); sleep duration was categorized into short (<6 h/night), normal (6–8.5 h/night), and long (>8.5 h/night) sleep. Presence of pain, chronic pain, and pain severity were ascertained through a self-administered questionnaire. ? coefficient, odds ratio (OR), and proportion mediated were estimated using counterfactual-based mediation models.

Results

Approximately half of the participants (47%, n=815) reported experiencing pain, with 40.8% (n=689) reporting chronic pain. Among 699 participants with reported experiencing pain and pain severity data, the mean pain severity score was 3.6 (SD=1.7). Our findings revealed that sleep quality accounted for 30% of educational, 21% of occupational, and 45% of income-related inequities in self-reported pain. Furthermore, sleep quality accounted for 20% of occupation and 51% of income inequities in chronic pain, as well as 15%, 9%, and 16% of father’s occupation, educational, and income inequities in pain severity, respectively. Additionally, we found that short sleep duration accounted for 31% of education-related inequities in pain and about 37% of both education and income-related inequities in chronic pain.

Conclusions

Our results indicated that up to 51% of socioeconomic inequities in self-reported pain, chronic pain, and pain severity are explained by sleep quality and short sleep duration. These findings imply that interventions targeting sleep could offer benefits to socioeconomically disadvantages individuals and potentially help mitigate the socioeconomic inequities in the burden of pain.

References

1.Blyth FM. Chronic pain–is it a public health problem? Pain United States; 2008. p. 465–466.
2.Blyth FM, Windt DA Van Der, Croft PR. Chronic Disabling Pain: A Significant Public Health Problem. Am J Prev Med. Netherlands; 2015 Jul;49(1):98–101.
3.Khalatbari-Soltani S; Blyth FM. Socioeconomic position and pain: a topical review. PAIN 163(10):p 1855-1861, October 2022.
4.Finan PH, Goodin BR, Smith MT. The association of sleep and pain: an update and a path forward. J pain [Internet]. 2013 Dec;14(12):1539–1552.
5.Davies KA, Silman AJ, Macfarlane GJ, et al. The association between neighbourhood socio-economic status and the onset of chronic widespread pain: results from the EPIFUND study. Eur J Pain. 2009 Jul;13(6):635–640.
6.Brooks Holliday S, Dubowitz T, Ghosh-Dastidar B, et al. Do Sleep and Psychological Distress Mediate the Association Between Neighborhood Factors and Pain? Pain Med. 2019 Feb;20(2):278–289.

Presenting Author

Fiona M. Blyth

Poster Authors

Saman Khalatbari-Soltani

PhD

University of Sydney School of Public Health

Lead Author

E-mail

Dusan Petrovic

PhD

Center for Primary Care and Public Health (Unisanté), University of Lausanne

Lead Author

E-mail

Carlos de Mestral

PhD

Unit of Population Epidemiology, Geneva University Hospitals

Lead Author

E-mail

Pedro Marques-Vidal

PhD

Department of Medicine, Lausanne University Hospital (CHUV)

Lead Author

E-mail

Fiona Blyth

University of Sydney

Lead Author

E-mail

Topics

  • Epidemiology