Relationship between changes in blood pressure and left ventricular mass over 1 year in end-stage renal disease

OBJECTIVE: The optimal timing of blood pressure (BP) measurement is not firmly established for patients undergoing hemodialysis. We sought to assess which BP measurement change best correlates with changes in left ventricular mass index (LVMI) over 1 year in patients with end-stage renal disease. METHODS: Fifty-seven patients were included in a prospective cohort study comparing the cardiovascular impact of conversion to in-center nocturnal hemodialysis versus continuing conventional hemodialysis. BP measurements were recorded at different time points (predialysis, after initiation of dialysis, at the intradialytic nadir, and postdialysis) during dialysis sessions over 12 weeks at baseline and after 1-year follow-up. LVMI was independently measured by a single blinded reader using cardiac magnetic resonance imaging at baseline and 1 year. RESULTS: Overall, the mean LVMI was 69.9 g/m (standard deviation 15.9) at baseline and 69.6 g/m (standard deviation 16.0) at 1 year. The change in initiation mean arterial pressure (MAP) most strongly correlated with the change in LVMI (Pearson correlation coefficient r = 0.71, P < 0.001). The relationship was similar in both dialysis groups and in multivariable analysis. In pairwise comparisons, initiation MAP was more strongly correlated with the change in LVMI than nadir and postdialysis measurements (all P < 0.05). However, the correlation was not stronger than predialysis SBP (P = 0.33). CONCLUSION: The change in initiation MAP correlated best with the change in LVMI over 1 year in patients undergoing hemodialysis. Further studies are needed to determine whether it represents a potentially useful treatment target to prevent adverse ventricular remodeling, thereby improving cardiovascular outcome.ClinicalTrials.gov Identifier: NCT00718848.