Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
Clinical Journal of the American Society of Nephrology
Year: 2010  |  Volume: 5  |  Issue: 7  |  Page No.: 1243 - 1248

Modeling Survival of Arteriovenous Accesses for Hemodialysis: Semiparametric versus Parametric Methods

P Ravani, P Parfrey, J MacRae, M James, R Quinn, F Malberti, G Brunori, S Mandolfo, M Tonelli, B Hemmelgarn, B Manns and B. Barrett    

Abstract:

Background and objectives: Comparing outcomes of arteriovenous grafts and fistulas is challenging because the pathophysiology of access dysfunction and failure rate profiles differ by access type. Studying how risks vary over time may be important.

Design, setting, participants, & measurements: Longitudinal data from 535 incident hemodialysis patients were used to study the relationship between access type and access survival, without (semiparametric Cox modeling) and with specification of the underlying hazard function (parametric Weibull modeling).

Results: The hazard for failure of fistulas and grafts declined over time, becoming proportional only after 3 months from surgery, with a graft versus fistula hazard ratio of 3.2 (95% confidence interval 1.9 to 5.3; Cox and Weibull estimation) and time ratio of 0.11 (i.e., the estimated access survival time was approximately one tenth shorter in grafts; 95% confidence interval 0.04 to 0.28; Weibull estimation only). Considering the entire observation period, grafts had slower hazard decline (P < 0.001) with shorter median survival times than fistulas (8.4 versus 38.3 months; Weibull regression only).

Conclusions: Parametric models of arteriovenous access survival may provide relevant information about temporal risk profiles and predicted survival times.

View Fulltext    |   Related Articles   |   Back
   
 
 
 
  Related Articles

No Article Found
 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility