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Yazdani Babak; Kleber Marcus E.; Delgado Graciela E.; Yücel Gökhan; Asgari Aruscha; Gerken Andreas L.H.; Daschner Clara; Ayasse Niklas; März Winfried; Wanner Christoph; Krämer Bernhard K.: Blood pressure and Mortality in the 4D Study. Kidney and Blood Pressure Research DOI 10.1159/000533136
The relationship of blood pressure (BP; systolic, diastolic, pulse pressure, mean arterial pressure) in dialysis patients with diabetes is greatly complicated by competing risks and co-morbidities. Many studies failed to show strong predictive power of (pre-dialysis) BP for all-cause (ACM) and cardio-vascular (CVM) mortality.
Yazdani and co-workers retrospectively analyzed the large 4D trial (in Germany) of the effect of lipid control with statins in diabetic hemodialysis patients (n = 1,255) for the impact of BP on ACM and CVM during a follow-up period averaging about 8 months.
The values of systolic BP, diastolic BP, pulse pressure, and mean arterial pressure were not predictive of ACM and CVM, after adjustments for age and sex. However, a U-shaped relationship of pulse pressure was observed for ACM and CVM, with a rough value of 70–80 mm Hg.
In diabetic patients with end-stage kidney disease (ESKD) treated by dialysis, many co-morbid factors contribute to the risks of ACM and CVM, not all of which are captured by BP parameters. The patients included in this study were “prevalent” patients with an average diabetes duration of 18 years and a dialysis duration at the time of enrolment of about 6 months. The follow-up was relatively short (only 8 months).
This study “only” generates a plausible hypothesis that both low and high pulse pressure is a potentially causative factor in generating a higher risk for ACM and CVM in diabetic patients on dialysis. It remains to be shown that better long-term control of pulse pressure would improve the frequency of these outcomes, especially in an incident population of ESKD. Pulse pressure is largely a phenomenon related to dispensability of larger vessels and cardiac stroke volume, both factors that are difficult to influence. Systolic BP is also closely related to the degree of volume overload in patients with ESKD. This in an interesting and valuable addition to the literature on the potential impact of BP parameters on outcomes in diabetic dialysis patients, but the optimal levels needed to assure better outcomes remain uncertain.
