The timely construction of arteriovenous fistulae: a key to reducing morbidity and mortality and to improving cost management

Abstract

Background: Some investigators have shown that the initial placement of a catheter or graft, instead of the timely construction of an arteriovenous fistula (AVF), late referral to nephrology services and unplanned dialysis increase morbidity and mortality in chronic haemodialysis (CHD) patients. Furthermore, a delay in providing an adequate AVF entails significant increases in treatment-related costs. This study was limited to the analysis of the effects of the lack of an adequate vascular access for CHD on morbidity and mortality.

Methods: According to the vascular access they had in the first 3 months of CHD treatment 96 patients were divided into three groups (VA group): Group 1 (G1), having an adequate AVF in the first 3 months; Group 2 (G2), starting with a catheter but finishing with an AVF; and Group 3 (G3) starting and finishing with a catheter. Time-dependent Cox regression analysis was performed to identify variables associated with survival, and the standardized mortality index (SMI) was calculated. Finally, we studied cost-effectiveness.

Results: Time-dependent Cox regression and logistic regression analyses showed the statistically significant variable to be the VA group. To ensure that mortality was comparable between VA groups, eliminating age bias, the findings were adjusted applying SMI. G1 patients appear to have a lesser risk of death (relative risk, 0.39) than G2 and G3 patients, as do G2 relative to G3 patients. Also, after adjustment with SMI, patients over 65 years, presumably at greater risk of death, have a lower mortality than the <or=65 age group. Patients with an adequate and functioning AVF lived longer than the others, and the cost of each 'death prevented' was lower (3318/patient).

Conclusions: The lack of an adequate AVF at the start of haemodialysis decreases survival significantly-even if patients are not diabetic, are referred to a nephrologist early and planned haemodialysis is initiated. It also increases the cost of each prevented death.