Severe hemodialysis access-induced distal ischemia may be associated with poor survival

Abstract

Background: Some hemodialysis patients develop hemodialysis access-induced distal ischemia due to insufficient loco-regional perfusion pressure and consequent poor arterial flow. We hypothesized that patients with severe hemodialysis access-induced distal ischemia had worse survival compared with patients with mild or no hemodialysis access-induced distal ischemia. Methods: This single-center retrospective observational cohort study included three groups of prevalent hemodialysis patients with an upper extremity vascular access between 2006 and 2018. Symptomatic patients had signs and symptoms of hemodialysis access-induced distal ischemia and low digital brachial indices (<60%) and were divided into a mild (Grade I–IIa) and a severe hemodialysis access-induced distal ischemia (IIb–IV) group. The control group consisted of hemodialysis patients without signs of hemodialysis access-induced distal ischemia with digital brachial indices ≥60%. Factors potentially related to 4-year survival were analyzed. Results: Mild hemodialysis access-induced distal ischemia-patients displayed higher digital brachial indices ( n = 23, 41%, ±3) compared with severe hemodialysis access-induced distal ischemia-patients ( n = 28, 24%, ±4), whereas controls had the highest values ( n = 48, 80%, ±2; p < .001). A total of 44 patients (44%) died during follow-up. Digital brachial index (hazards ratio 0.989 [0.979–1.000] p = .046) was related to overall mortality following correction for presence of arterial occlusive disease (hazards ratio 2.28 [1.22–4.29], diabetes (hazards ratio 2.00 [1.07–3.72], and increasing age (hazards ratio 1.03 [1.01–1.06] as was digital pressure (hazards ratio 0.990 [0.983–0.998], p = .011). Overall survival was similar in mild hemodialysis access-induced distal ischemia and controls (2-year, 79% ±5; 4-year, 57% ±6, p = .818). In contrast, 4-year survival was >20% lower in patients with severe hemodialysis access-induced distal ischemia (2-year 62%± 10; 4-year 34% ± 10; p = .026). Conclusion: Presence of severe hemodialysis access-induced distal ischemia may be associated with poorer survival in hemodialysis patients. Lower digital brachial index values are associated with higher overall mortality, even following correction for other known risk factors.