An evaluation of the association between C-reactive protein, the change in C-reactive protein over one year, and all-cause mortality in chronic immune-mediated inflammatory disease managed in UK general practice
1Pharmatelligence, Medicentre, University Hospital of Wales, Cardiff, 2Health Economics, Wyeth Europa Limited, Maidenhead and 3Department of Medicine, School of Medicine, Cardiff University, Cardiff, UK.
Correspondence to: C. J. Currie, Department of Medicine, School of Medicine, Cardiff University, University Hospital of Wales, Cardiff CF14 4XW, UK. E-mail: currie{at}cardiff.ac.uk
 |
Abstract |
|---|
Objectives. To evaluate the association between systemic inflammation, as measured by CRP, and all-cause mortality. To also evaluate the association between change in CRP status (sub-acute, 
10 mg/l and acute >10 mg/l) and all-cause mortality.
Methods. A cohort of patients was selected from The Health Improvement Network (THIN) data set of anonymized patient-level data from UK general practice. Patients were selected if they had a diagnosis of RA, psoriasis, AS or PsA. Survival was evaluated using Cox proportional hazards regression models (CPHMs).
Results. A total of 11 362 cases had at least one CRP measurement. Analysis grouped by each additional unit increase in log-CRP (range 1–6) across the observed range was associated with a 21% increase in the hazard ratio (HR) of death, after controlling for cardiovascular risk factors (P < 0.001). This observation was consistent in separate analysis of cases with either RA or psoriasis. Repeated CRP observations around 1 yr apart were recorded in 2802 subjects. After controlling for confounding factors, in cases whose CRP changed from sub-acute (10 mg/l) to acute (>10 mg/l), the HR for death increased 2-fold (P < 0.001) relative to cases whose CRP remained sub-acute. In comparison, among those subjects whose CRP was reduced from acute to sub-acute, the HR was virtually identical to those who stayed sub-acute (P = 0.571).
Conclusions. CRP level predicted all-cause mortality after standardization for traditional risk factors, as did change in CRP status from sub-acute to acute observed over 1 yr.
KEY WORDS: C-reactive protein, Systemic inflammation, Survival, Rheumatoid arthritis, Psoriasis, Ankylosing spondylitis, Psoriatic arthritis
Submitted 3 December 2007;
revised version accepted 26 September 2008.
CiteULike 
Connotea 
Del.icio.us What's this?