Effects of three times weekly eight-hour nocturnal hemodialysis on volume and nutritional status.

BACKGROUND: This prospective cohort study compared the changes in body water composition and nutritional parameters measured with multifrequency bioimpedance analysis between 8-hour three times weekly nocturnal hemodialysis (NHD) and 4-hour conventional hemodialysis (CHD) patients. PATIENTS AND METHODS: 55 patients on CHD and 57 patients on NHD were included in the study. Multifrequency bioimpedance analysis was performed at baseline and at the 12th month. The primary outcomes of the study were changes in extracellular water (ECW), fat mass, dry lean mass and phase angle. Secondary outcomes of the study included changes in blood pressure and biochemical parameters related to nutrition and inflammation. RESULTS: ECW/height values decreased in the NHD group, while they increased in the CHD group. Fat mass, dry lean mass, and serum albumin increased and high sensitive CRP decreased in the NHD group but did not change in the CHD group. When changes in parameters from baseline to the 12th month between the groups were compared, NHD was associated with improvement in volume parameter including ECW/height (difference -0.44 l/m, p < 0.001). Change in blood pressure was not different between the groups, however requirement for antihypertensive medication decreased from 26.5 to 8.5% in the NHD group (p = 0.002). NHD was also associated with increases in fat mass (difference 1.8 kg, p < 0.001), dry lean mass (difference 0.6 kg, p = 0.006), serum albumin (difference 0.19 g/dl, p < 0.001) and cholesterol (difference 18.8 mg, p < 0.001). Phase angle values decreased in the CHD group but did not change in the NHD group (difference between the groups 0.37°, p = 0.04). CONCLUSION: This study revealed that longer HD facilitates volume control and improves nutritional status.

Interdialytic blood pressure obtained by ambulatory blood pressure measurement and left ventricular structure in hypertensive hemodialysis patients.

Unlike in subjects with normal renal function, the relationship between hypertension and cardiovascular morbidity and mortality in dialysis patients is still being debated. In order to clarify this issue, we performed 44-hour ambulatory blood pressure measurements (ABPM) during the interdialytic period in a group of 164 hypertensive patients, the blood pressure (BP) control based on conventional antihypertensive strategy previously, on chronic hemodialysis treatment in the Mediterranean region of Turkey. These results were then compared with their echocardiographic data. This is a cross-sectional analysis. The mean ABPM during 44 hours was close to the manually measured predialysis value, but there was a gradual increase in the ABPM values in the interdialytic period. When divided into a group with mild or no left ventricular hypertrophy (LVH) (45 patients) and severe LVH (119 patients), the latter had significantly higher BP levels in all separate periods, while the difference in predialysis BP was not significant. Patients with severe LVH had larger left atrium and left ventricular diameters, and consumed more antihypertensive drugs. Systolic BP during the night before dialysis showed the strongest relation to LVH, but interdialytic weight gain was also independently related to LVH. Yet, 56% of the patients with systolic BP <135 had severe LVH. There is not only an association between BP and presence of LVH, but it is shown that volume expansion is also an important independent determinant of LVH. This may explain the difficulty in identifying hypertension as a cardiac risk factor in these patients.