The association between neighbourhood socio-economic status and the onset of chronic widespread pain: results from the EPIFUND study.
BACKGROUND
Cross-sectional studies have reported an inverse relationship between socio-economic status and the prevalence of chronic widespread pain (CWP). However, the extent to which this relationship is explained by psychological factors is unknown. The aim of this study was to examine the hypothesis that socio-economic status predicts the onset of CWP but that this relationship would be explained by psychological factors.


METHODS
Subjects from three diverse socio-economic areas were recruited into a population-based prospective survey of pain. Subjects completed a questionnaire at baseline that assessed pain status and psychological factors and occupation. Fifteen months later subjects completed a follow-up questionnaire which assessed pain status.


RESULTS
A total of 3489 subjects were free of CWP at baseline and eligible for follow-up, of whom 2782 (79.7%) participated. Of those, 281 (10%) subjects were classified as having new CWP. Logistic regression analysis revealed that compared to subjects from the most affluent socio-economic area, those from the moderate and least affluent areas were respectively, 1.47 (95% CI: 1.08-2.01) and 1.35 (95% CI: 1.00-1.82) times more likely to have new CWP. However, in a stepwise multivariate logistic regression analysis, controlling for psychological factors, the relationship between new onset CWP and socio-economic status was no longer evident.


CONCLUSIONS
This study has demonstrated that socio-economic status is related to new onset CWP, but the association is explained by psychological factors. Understanding the factors underlying the association between socio-economic status and pain should help to design intervention strategies which may reduce the burden of chronic pain in identified high risk population groups.
Davies
Kelly A
KA
Arthritis Research Campaign (ARC), Epidemiology Unit, Research School of Translational Medicine, Stopford Building, University of Manchester, Manchester, United Kingdom. Kelly.davies@manchester.ac.uk
Silman
Alan J
AJ
Macfarlane
Gary J
GJ
Nicholl
Barbara I
BI
Dickens
Chris
C
Morriss
Richard
R
Ray
David
D
McBeth
John
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D001007:Anxiety / Q000523:psychology; D002908:Chronic Disease; D005260:Female; D006801:Humans; D055809:Illness Behavior; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009790:Occupations; D010146:Pain / Q000191:economics* / Q000453:epidemiology* / Q000523:psychology; D010147:Pain Measurement; D018579:Patient Selection; D011153:Population; D012111:Residence Characteristics; D012923:Social Class; D011795:Surveys and Questionnaires; D055815:Young Adult
J Psychosom Res. 1996 Jan;40(1):95-104
8730649
Arthritis Rheum. 1990 Feb;33(2):160-72
2306288
Am Psychol. 1994 Jan;49(1):15-24
8122813
Psychol Med. 1985 Feb;15(1):189-94
3991833
J Psychosom Res. 2001 Oct;51(4):563-9
11595244
J Rheumatol. 2001 Jun;28(6):1369-77
11409133
Joint Bone Spine. 2005 May;72(3):254-9
15850998
J Psychosom Res. 2002 Oct;53(4):891-5
12377299
Pain. 2005 Apr;114(3):364-371
15777862
Soc Sci Med. 2002 Jan;54(2):221-8
11824927
Arthritis Rheum. 1999 Jul;42(7):1397-404
10403267
J Rheumatol. 1996 Sep;23(9):1628-32
8877936
Am J Psychiatry. 1985 Oct;142(10):1146-9
4037124
Rheumatology (Oxford). 2003 Dec;42(12):1486-94
12867586
J Pain. 2004 Aug;5(6):317-28
15336636
Rheumatology (Oxford). 2007 Apr;46(4):666-71
17085772
Spine (Phila Pa 1976). 1995 Dec 15;20(24):2731-7
8747252
Acta Psychiatr Scand. 1983 Jun;67(6):361-70
6880820
J Clin Epidemiol. 1988;41(4):313-21
3351539
Ann Rheum Dis. 2002 Dec;61(12):1071-4
12429537
Br Dent J. 2003 Apr 12;194(7):383-7; discussion 380
12821918
Arthritis Rheum. 2001 Apr;44(4):940-6
11315933
Int J Equity Health. 2004 Oct 19;3(1):10
15494077
J Epidemiol Community Health. 2003 Jun;57(6):444-52
12775792
Arthritis Rheum. 2000 Mar;43(3):561-7
10728749