Risk factors associated with abdominal aortic aneurysm: a population-based study with historical and current data.
OBJECTIVE
To define risk factors associated with the development of abdominal aortic aneurysm (AAA) in a population-based case-control study.


METHODS
Thirty-five patients found to have AAA at screening were compared with 140 age- and sex-matched controls. Three distinct comparisons were made. Current risk factors in both cohorts were compared. Because data were also available for both cohorts from a study conducted 12 years previously, a historical comparison was made between risk factors identified at the time of this initial evaluation. A longitudinal comparison was made between historical and current risk factors.


RESULTS
Elevated low-density-lipoprotein cholesterol, total cholesterol, and triglyceride levels 12 years before AAA screening were associated with current AAA with an odds ratio (OR) of 2.3 (95% confidence interval [CI], 1.2 to 4.4); OR, 1.9 (95% CI, 1.3 to 2.8); and OR, 1.9 (95% CI,1.2 to 3.1)/mmol/L, respectively. Current variables assessed at AAA screening that were associated with AAA were: A history of atherosclerotic disease, OR, 3.8 (95% CI, 1.7 to 8.5); having a first-degree relative with AAA, OR, 4.4 (95% CI, 1.5 to 13.0); current smoking, OR, 5.2 (95% CI, 1.6 to 16.8); high-density-lipoprotein cholesterol level, OR, 0.1 (95% CI, 0.02 to 0.7)/mmol/L; and high-sensitivity C-reactive protein (hsCRP) level, OR, 1.1 (95% CI, 1.01 to 1.2)/mg/L. Hypertension and diabetes were not associated with AAA. A significant increase of hsCRP over time (12 years) was observed in AAA patients ( P = .039) but not among controls. The variables of a history of atherosclerosis, smoking, and family history of AAA appear to interact synergistically to increase the prevalence of AAA ( P < .001).


CONCLUSIONS
Among traditional risk factors for atherosclerosis, some were associated with AAA and others were not, indicating complex and partly different causes. Inflammation and heredity appear to be important factors in the development of AAA.
Wanhainen
Anders
A
Department of Surgery, Uppsala University Hospital, SE-372 Uppsala, Sweden. andwan@algonet.se
Bergqvist
David
D
Boman
Kurt
K
Nilsson
Torbjörn K
TK
Rutegård
Jörgen
J
Björck
Martin
M
D000367:Age Factors; D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000097:blood / Q000453:epidemiology* / Q000235:genetics; D001161:Arteriosclerosis / Q000453:epidemiology*; D002097:C-Reactive Protein / Q000032:analysis; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D016017:Odds Ratio; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology
D002097:C-Reactive Protein