Long term reduction of cardiovascular risk factors associated with three hour daily dialysis: A prospective, cohort study

Abstract

Introduction: Daily hemodialysis (DHD) compared to conventional hemodialysis (CHD) leads to improvements in left ventricular hypertrophy and mineral metabolism at 1-year follow-up. However, there is no information from prospective studies on the long terms effects of DHD on these key cardiovascular risk factors.

Methods: We conducted a 4 year, prospective cohort study of 26 DHD and 51 matched CHD patients on the effect of DHD (six sessions/week × 3 h) versus CHD (three sessions/week × 4 h), 15 DHD, and 26 CHD patients completed 4-years follow-up. Measures of left ventricular mass index (LVMI), blood pressures, hemoglobin, and mineral metabolism markers were performed.

Results: Systolic and diastolic blood pressures were significantly lower in the DHD group than the CHD group at 4-year follow-up, 128 mmHg (95% CI, 111-143) versus 148 mmHg (95% CI, 137-158) (p < 0.05) and 60 mmHg (95% CI, 56-63) versus 71 mmHg (95% CI, 64-76) (p < 0.05). DHD was associated with fewer patients taking any anti-hypertensive drug therapy than CHD, 50% versus 80% (p < 0.05). DHD was associated with improved attainment of mineral metabolism goals for phosphorus (adjusted HR 3.6, p = 0.002) and calcium × phosphorus product (adjusted HR 3.66, p = 0.001) at 4-years follow-up compared to CHD. At 4 years, there was a nonsignificant trend toward lower LVMI in the DHD than in the CHD group: 116 g/m² (95% CI, 97-136) versus 138 g/m² (95% CI, 115-172) (p = 0.23). Similarly, improvements in hemoglobin also persisted at 4 years follow-up.

Conclusion: DHD is associated with long-term (4 year) improvements in key cardiovascular risk factors: blood pressure, mineral metabolism, and anemia with trends toward improved LVMI.

Keywords: adequacy of dialysis; cardiovascular; daily dialysis.