Impact of Ambulation Status in Patients with End-stage Renal Disease on Hemodialysis due to Diabetic Nephropathy : The PREDICT Study

Background : Hemodialysis (HD) patients often have severe morbidity and mortality, with critical limb ischemia (CLI) being a cause of major amputation and death. In the clinical setting, the predictive ability of patient ambulatory status on outcome in patients on HD due to diabetic nephropathy (DN) is not well known. Aim : To investigate the association of ambulatory status with clinical outcome in end-stage renal disease patients on HD and its predictive ability for CLI-free survival. Methods : In the multi-center, observational Prospective REgistry with the DIalysis patient due to diabetes to prevent CriTical limb ischemia (PREDICT) study, 173 patients on HD due to DN were enrolled between April 2012 and August 2013 from 9 institutions. We investigated ambulatory status, ankle-brachial index, lower limb artery lesions by duplex ultrasound, and laboratory findings every 6 months for 2 years. The primary endpoint was CLI-free survival at 2 years. Results : Complete follow-up was possible for 164 patients (94.2 %) at 2 years. Average age was 68 (range : 58-74) years and average HD duration was 49.4 (range : 23.5-90.5) months. The CLI-free survival rate of ambulatory patients was significantly higher than that of non-ambulatory patients (84.9 % vs. 62.7 %, p=0.0006). Survival rate was also significantly higher in the ambulatory group (89.2 % vs. 69.8 %, p=0.01). Cox regression analysis revealed a significant association between ambulatory status and CLI or death (hazard ratio 6.06, 95 % confidence interval 1.34-732.3 ; p=0.02). Conclusion : This study revealed that ambulatory status might predict mid-term CLI-free survival in HD patients with DN.