Hemodynamic and biochemical benefits of the objective measurement of fluid status in hemodialysis patients.

Subtle fluid imbalance can cause poor clinical outcomes among hemodialysis patients. However, the traditional subjective assessment of fluid status may be inadequate. We evaluated whether the objective measurement and optimization of fluid status could be beneficial for hemodynamic and biochemical parameters in hemodialysis patients. We enrolled 120 hemodialysis patients, who were clinically euvolemic for at least 3 months. Based on the results of a body composition monitor, we divided the patients into the following two groups: the hyperhydrated group (post hemodialysis fluid overload ≥ 1.1 L) and the dehydrated group (post hemodialysis fluid overload < -1.1 L). We reduced the patient's body weight in the hyperhydrated group and raised the body weight in the dehydrated group towards normohydration (-1.1 L ≤ fluid overload < 1.1 L) for 16 weeks. Forty-four of 120 patients were in the hyperhydrated group, and 18 of 120 patients in the dehydrated group. After 16 weeks, systolic blood pressure and pulse pressure decreased in the hyperhydrated group, while there was no increase in blood pressure in the dehydrated group after the intervention. Serum levels of monocyte chemotactic protein-1, an inflammatory marker, gradually decreased in the hyperhydrated group, and serum adiponectin levels, an anti-atherogenic biomarker, increased in the two groups. We found that hyperhydrated patients contributed over 1/3 of the participants despite enrolling clinically euvolemic patients and that body composition monitor-guided optimization of body fluid status may lead to improvement of inflammatory markers and anti-atherogenic adipokines as well as hemodynamic parameters in hemodialysis patients.