Does a history of depression actually mediate smoking‐related pain? Findings from a cross‐sectional general population‐based study. (27th February 2014)

• Record Type: Journal Article
• Authors: van Hecke, O.; Torrance, N.; Cochrane, L.; Cavanagh, J.; Donnan, P.T.; Padmanabhan, S.; Porteous, D.J.; Hocking, L.; Smith, B.H.
• Is Part Of: European journal of pain. Volume 18:Number 9(2014)
• Page Start: 1223
• Page End: 1230
• Publication Date: 2014-02-27
• Subjects: Pain -- Periodicals; Pain -- Treatment -- Periodicals; Pain -- Physiological aspects -- Periodicals; 616.0472
• DOI: 10.1002/j.1532-2149.2014.00470.x
• Languages: English
• ISSNs: 1090-3801

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <sec id="ejp470-sec-0001" sec-type="section"> <title>Background</title> <p>Smokers report more pain and worse functioning. The evidence from pain clinics suggests that depression affects this relationship: The association between smoking and chronic pain is weakened when controlling for depression. This study explored the relationship between smoking, pain and depression in a large general population‐based cohort (Generation Scotland: Scottish Family Health Study).</p> </sec> <sec id="ejp470-sec-0002" sec-type="section"> <title>Methods</title> <p>Chronic pain measures (intensity, disability), self‐reported smoking status and a history of major depressive disorder (MDD) were analysed. A multivariate analysis of covariance determined whether smoking status was associated with both pain measures and a history of depressive illness. Using a statistical mediation model any mediating effect of depression on the relationship between smoking and chronic pain was sought.</p> </sec> <sec id="ejp470-sec-0003" sec-type="section"> <title>Results</title> <p>Of all 24, 024 participants, 30% (<italic>n</italic> = 7162) reported any chronic pain. Within this chronic pain group, 16% (<italic>n =</italic> 1158) had a history of MDD; 7108 had valid smoking data: 20% (<italic>n =</italic> 1408) were current smokers, 33% (<italic>n =</italic> 2351) former and 47% (<italic>n =</italic> 3349) never smokers. Current smokers demonstrated higher pain intensity and pain‐related disability scores compared with former and non‐smokers (<italic>p</italic> < 0.001 for all analyses). From the mediation model, the effect on pain intensity decreased (<italic>p</italic> < 0.001), indicating that the relationship between smoking and a history of depression contributes significantly to the effect of smoking on pain intensity. When applied to smoking‐related pain disability, there was no mediation effect.</p> </sec> <sec id="ejp470-sec-0004" sec-type="section"> <title>Conclusions</title> <p>In contrast to smokers treated in pain clinics, a history of MDD mediated the relationship between smoking and pain intensity, but not pain‐related disability in smokers in the community.</p> </sec> </abstract>