title: Plasma cathepsin S and cystatin C levels and risk of abdominal aortic aneurysm: a randomized population-based study.
abstract: BACKGROUND
  Human abdominal aortic aneurysm (AAA) lesions contain high levels of cathepsin S (CatS), but are deficient in its inhibitor, cystatin C. Whether plasma CatS and cystatin C levels are also altered in AAA patients remains unknown.
  
  
  RESULTS
  Plasma samples were collected from 476 male AAA patients and 200 age-matched male controls to determine CatS and cystatin C levels by ELISA. Student's t test demonstrated higher plasma levels of total, active, and pro-CatS in AAA patients than in controls (P<0.001). ROC curve analysis confirmed higher plasma total, active, and pro-CatS levels in AAA patients than in controls (P<0.001). Logistic regression suggested that plasma total (odds ratio [OR] = 1.332), active (OR = 1.21), and pro-CatS (OR = 1.25) levels were independent AAA risk factors that associated positively with AAA (P<0.001). Plasma cystatin C levels associated significantly, but negatively, with AAA (OR = 0.356, P<0.001). Univariate correlation demonstrated that plasma total and active CatS levels correlated positively with body-mass index, diastolic blood pressure, and aortic diameter, but negatively with the lowest ankle-brachial index (ABI). Plasma cystatin C levels also correlated negatively with the lowest ABI. Multivariate linear regression showed that plasma total, active, and pro-CatS levels correlated positively with aortic diameter and negatively with the lowest ABI, whereas plasma cystatin C levels correlated negatively with aortic diameter and the lowest ABI, after adjusting for common AAA risk factors.
  
  
  CONCLUSIONS
  Correlation of plasma CatS and cystatin C with aortic diameter and the lowest ABI suggest these serological parameters as biomarkers for human peripheral arterial diseases and AAA.
authors: Institute of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China.
authors: Bing-Jie
authors: BJ
authors: Lv
authors: Jes S
authors: JS
authors: Lindholt
authors: Xiang
authors: X
authors: Cheng
authors: Jing
authors: J
authors: Wang
authors: Guo-Ping
authors: GP
authors: Shi
mesh_terms: D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000097:blood* / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D001794:Blood Pressure; D002403:Cathepsins / Q000097:blood*; D015331:Cohort Studies; D055316:Cystatin C / Q000097:blood*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D006973:Hypertension / Q000150:complications; D008297:Male; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects
chemical_list: D055316:Cystatin C; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D002403:Cathepsins; C028217:cathepsin S