C-reactive protein levels and the expansion of screen-detected abdominal aortic aneurysms in men.
BACKGROUND
C-reactive protein (CRP) levels have been shown to predict a number of cardiovascular outcomes. CRP levels have also been found to be elevated in patients with abdominal aortic aneurysms (AAAs). The aim of this study was to assess the relation between CRP levels and rates of expansion of small AAAs.


RESULTS
A cohort of men with small aneurysms was identified in a trial of screening with ultrasound scanning. After initial screening, men were rescanned at 6- to 12-month intervals. CRP levels were measured at the first follow-up visit. Rates of expansion and risk factors for expansion were assessed with the use of data from 545 men who attended for at least 1 scan after CRP levels were measured. These men were followed for a median of 48 (range, 5 to 69) months. The mean annual rate of expansion was 1.6 mm. The median CRP level was 2.6 mg/L in men with the smaller AAAs (30 to 39 mm, n=433) compared with 3.5 mg/L in men with larger AAAs (40 to 54 mm, n=112) (P=0.007). The multivariate age-adjusted logistic model confirmed initial aortic diameter to be the only factor associated with rapid expansion with an odds ratio of 7.2 (95% CI, 4.3,12.2) for an initial diameter of 40 to 54 mm relative to one of 30 to 39 mm.


CONCLUSIONS
Most small aneurysms expand slowly. CRP levels are elevated in larger aneurysms but do not appear to be associated with rapid expansion. The most useful predictor of aneurysmal expansion in men is aortic diameter.
School of Surgery and Pathology, The University of Western Australia, Fremantle Hospital, Fremantle, Western Australia. pnorman@cyllene.uwa.edu.au.
Paul
P
Norman
Carole A
CA
Spencer
Michael M
MM
Lawrence-Brown
Konrad
K
Jamrozik
D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry; D001012:Aorta, Abdominal / Q000473:pathology; D017544:Aortic Aneurysm, Abdominal / Q000097:blood* / Q000000981:diagnostic imaging / Q000473:pathology; D015415:Biomarkers; D002097:C-Reactive Protein / Q000032:analysis*; D015331:Cohort Studies; D018450:Disease Progression; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008403:Mass Screening; D014463:Ultrasonography
D015415:Biomarkers; D002097:C-Reactive Protein