Open AccessAssociations between inflammation, nocturnal back pain and fatigue in ankylosing spondylitis and improvements with etanercept therapy
Author(s) -
Mohammed Hammoudeh,
Debra Zack,
Wenzhi Li,
Vicky Stewart,
Andrew Koenig
Publication year - 2013
Publication title -
journal of international medical research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.421
H-Index - 57
eISSN - 1473-2300
pISSN - 0300-0605
DOI - 10.1177/0300060513488501
Subject(s) - medicine , ankylosing spondylitis , sulfasalazine , etanercept , placebo , visual analogue scale , spondylitis , low back pain , physical therapy , back pain , disease , rheumatoid arthritis , pathology , alternative medicine , ulcerative colitis
Objectives To investigate the relationships between inflammation, nocturnal back pain and fatigue in ankylosing spondylitis (AS) and the impact of 12 weeks' etanercept treatment versus sulfasalazine or placebo.Methods Data were combined from four clinical trials for patients with AS who received at least one dose of etanercept, sulfasalazine or placebo and had at least one postbaseline assessment value. Linear regression was performed (controlling for site, protocol and demographics), to explore the relationship between inflammation (C-reactive protein [CRP]), nocturnal back pain (visual analog scale [VAS] 0–100 mm) and fatigue (VAS 0–100 mm Bath AS Disease Activity Index fatigue item).Results Out of 1283 patients (etanercept, n = 867; sulfasalazine, n = 187; placebo, n = 229), improvement in nocturnal back pain was a significant predictor of improvement in fatigue. Significant correlations were found between nocturnal back pain and fatigue, but not CRP levels. Etanercept provided significantly greater pain/fatigue improvement than sulfasalazine or placebo. Improvements in nocturnal back pain and fatigue had weak relationships with improvement in inflammation (CRP level).Conclusions AS patients treated with etanercept demonstrated superior improvement in nocturnal back pain and fatigue versus sulfasalazine or placebo. Decrease in nocturnal back pain can improve fatigue. Assessing treatment response using CRP levels alone may be misleading without also examining patient-reported outcomes such as back pain and fatigue.