LONGITUDINAL COMPARISON OF DIALYSIS ACCESS METHODS - RISK-FACTORS FORFAILURE

Purpose: To compare dialysis access patency rates and identify risk fa ctors for failure. Methods: All access procedures at our institution f rom 1987 to 1996 were reviewed. Primary procedures were surgically imp lanted dual-lumen central venous hemodialysis catheters (SIHCs), perit oneal dialysis catheters (PDCs), arteriovenous fistulas (AVFs), and pr osthetic shunts (PTFEs). Results: Five hundred eighty-five primary pro cedures (236 PTFEs, 87 AVFs, 112 SIHCs, and 150 PDCs) and 259 secondar y procedures (215 PTFEs, 14 AVFs, 0 SIHCs, and 30 PDCs) were performed on 350 patients. By life table analysis, SIHCs exhibited the lowest p rimary patency rate (9% at 1 year; P < 0.0001), whereas PDCs had the h ighest primary patency rate (57% at 1 year; p < 0.02). The primary pat ency rates of AVFs and PTFEs was similar, with 43% and 41% 1-year pate ncy rates, respectively(p = 0.70). Less-stringent reporting methods wo uld have increased apparent 1-year patency rates by 9% to 41%. With re gard to secondary patency, there was no significant difference between PTFEs and PDCs, with 1-year patency rates of 59% and 70%, respectivel y (P = 0.62), but PTFEs were more frequently revised. In addition, the re was no significant: difference between AVF and PTFE secondary paten cy rates, with 1-year patency rates of 46% and 59%, respectively. Earl y differences in patency rates for AVFs, PTFEs, and PDCs diminished ov er time, and at 4 years AVFs had the best secondary patency rate (p = 0.6). The most common reasons for access failure were: PTFEs, thrombos is; AVFs, thrombosis and failure to mature; SIHCs, inadequate dialysis ; PDCs, infection and inadequate exchange. By regression analysis, a h istory of a previous unsalvageable PTFE was the only significant risk factor for failure of a subsequent PTFE (p < 0.01), and the risk of gr aft failure increased exponentially with the number of previous PTFE s hunts. Diabetes was the only significant risk factor for failure of PD Cs (p < 0.02; odds ratio, 2.0). Conclusions: The patency rate for PTFE s is similar to that for AVEs, but AVFs require fewer revisions. When replacing a failed access graft, the risk of PTFE failure increases wi th the number of prior unsalvageable PTEE shunts. PDCs have excellent patency rates, but failure rates are doubled in patients with diabetes . Because of poor patency rates and inadequate dialysis flow rates, SI HCs should be avoided when possible. Reporting methods dramatically af fect apparent patency rates, and reporting standards are needed to all ow meaningful comparisons in the dialysis access literature.