Hemodialysis (HD) vascular access type at the time of dialysis initiation may be an important modifier that can affect overall patient survival, according to a new Canadian study.
Previous research has shown that patients on peritoneal dialysis (PD) typically have higher early survival rates than patients on HD. It now appears that the difference in survival rate may be explained by a higher risk of early death in patients undergoing HD with central venous catheters (HD-CVC).
“Our results emphasize the importance of predialysis care and education, and the need to avoid central venous catheter use in our HD patients,” said first author Jeffrey Perl, MD, of St. Michael’s Hospital in Toronto.
Dr. Perl and his colleagues analyzed outcomes in 38,512 incident dialysis patients between 2001 and 2008. Among these patients, PD was the initial dialysis modality for 19%. Among HD patients, 21.4% initiated dialysis with an arteriovenous fistula or arteriovenous graft (AVF/AVG) and the remainder initiated HD with a CVC.
During the first year, the risk of death for patients starting HD with a CVC was 80% higher than for patients who started on PD, according to findings published (online ahead of print) in the Journal of American Society of Nephrology. The risk of death in the first year for patients who started HD with an AVF/AVG was similar to that of the PD group. In five years after starting dialysis, the risk of death was still 20% higher in patients who started HD with a central catheter compared with the PD group. The survival rate for patients who started HD with an AVF/AVG remained similar to that of patients who started on PD.
The researchers said these findings should prompt a reconsideration of conclusions drawn from previous studies comparing PD to HD. “These studies have been heavily criticized for comparing ‘apples to oranges,’” Dr. Perl said. “Their results may speak more towards the type of patients selected for PD over HD rather than a direct impact of PD versus HD itself on patients’ survival.” The current study is more of an “apples to apples” comparison of PD patients versus HD patients who have been “optimally prepared” with an AVF/AVG, he said.