End-stage renal disease patients with blocked carotid arteries have “very poor” long-term outcomes with endarterectomy, a retrospective study found, suggesting it might not be worthwhile for asymptomatic patients.
Stroke rates at 30 days were lower among the 83% of patients who were asymptomatic than those who were symptomatic (2.7% versus 5.2%, P=0.001), Mahmoud B. Malas, MD, MHS, of Johns Hopkins University in Baltimore, and colleagues reported in JAMA Surgery.
The 30-day rates were similar between the two for MI (4.6% versus 5.0%, P=0.69) and death (2.6% versus 2.9%, P=0.61).
In the long run, asymptomatic patients still held the advantage on stroke rates (5-year freedom from stroke 79% versus 69% for symptomatic arm, P<0.05).
However, while overall survival at 5 years also favored the asymptomatic patients, the rates were low either way at 33% and 22%, respectively (P<0.05).
“Although perioperative outcomes for asymptomatic patients are acceptable in our study, the long-term outcomes were very poor, with less than 50% of patients surviving to 3 years in both the asymptomatic and symptomatic cohorts,” the researchers wrote.
The authors noted that Society for Vascular Surgery guidelines recommend medical management for asymptomatic patients with less than 3 years of life expectancy. “Based on these findings, it is clear that asymptomatic hemodialysis patients do not derive long-term benefits from carotid endarterectomy over best medical therapy.”
But the message was less clear-cut for symptomatic patients: Although they showed relatively worse outcomes compared with the asymptomatic group, a prior systematic review showed even worse stroke rates — at 2 weeks, between 20.6% and 32.5% — with medical management alone. This points to a potential subgroup of symptomatic patients who do derive benefit from carotid endarterectomy, the authors suggested.
“The risks outweigh the benefits of carotid endarterectomy in asymptomatic patients and carotid endarterectomy should only be offered for a carefully selected cohort of symptomatic patients,” they concluded.
The study included 5,142 patients who underwent carotid endarterectomy between 2006 and 2011. Malas and colleagues gathered data from the U.S. Renal Disease System-Medicare matched database.
Predictors of perioperative stroke included symptomatic status (odds ratio [OR] 2.01, 95% CI 1.18-3.42), black race (OR 2.30, 95% CI 1.24-4.25), and Hispanic ethnicity (OR 2.28, 95% CI 1.17-4.42).
Linked to long-term stroke were perioperative symptoms (hazard ratio [HR] 1.67, 95% CI 1.24-2.24), female sex (HR 1.34, 95% CI 1.03-1.73), and inability to ambulate (HR 1.81, 95% CI 1.25-2.62).
Risk factors for long-term mortality were older age (OR 1.02, 95% CI 1.01-1.03), active smoking (OR 1.22, 95% CI 1.00-1.48), history of congestive heart failure (OR 1.25, 95% CI 1.12-1.39), and chronic obstructive pulmonary disease (OR 1.26, 95% CI 1.09-1.45).
“Owing to database limitations, we were not able to include information known to affect outcomes after carotid endarterectomy such as degree of stenosis, contralateral disease, medication use, or the duration of dialysis treatment prior to carotid endarterectomy,” Malas his colleagues acknowledged.
Another major limitation to the retrospective study was the lack of a medical-management control group.
In an accompanying editorial, Lily E. Johnston, MD, MPH, and Gilbert R. Upchurch, Jr, MD, both of University of Virginia at Charlottesville, added that carotid stenting results for comparison were also missing from the investigation.
The duo went on to question the generalizability of the data, the latest of which date back 5 years ago.
“It bears mentioning that our understanding of optimal medical therapy, the technology for carotid stenting, and even outcomes of carotid endarterectomy have all improved substantially over the last 5 to 10 years. That the patients in this study had operations between 2006 and 2011 may somewhat limit our ability to generalize these findings to current practice,” they commented.
Malas, Johnston, and Upchurch disclosed no relevant conflicts of interest.
Cooper M, et al “Perioperative and long-term outcomes after carotid endarterectomy in hemodialysis patients” JAMA Surg 2016; DOI: 10.1001/jamasurg.2016.1504.
Johnston LE, et al “High-risk patients in the evolving landscape of carotid revascularization” JAMA Surg 2016; DOI: 10.1001/jamasurg.2016.1505.