Dialysis Patients' Fluid Overload, Antihypertensive Medications, and Obesity

Abstract

Overhydration (OH) is both a major etiology of hypertension in hemodialysis patients and a serious risk factor for mortality. We investigated the association of multiple variables and OH. This is a cross-sectional study of prevalent hemodialysis patients examining the predialysis hydrational status with a portable bioimpedance apparatus to measure the degree of hydration. We completed our study in 79 patients. Patients were overhydrated by 2.6 ± 2.4 L. The mean medication count was 2.4 ± 1.5, and 50.7% had diuretics. We found a significant correlation between OH and systolic blood pressure (r = 0.39; p = 0.0006), each liter of OH generating 3.6 mm Hg. We also found a positive correlation between the use of diuretics and OH (p = 0.003, two-tailed Student's t test) but no correlation between OH and body weight (r < 0.0001; p = 0.99), body mass index (r = -0.17), age (r = 0.089), and vintage (r = 0.05). For every 10% increase in body fat, OH decreased by 1.2 L; residual urine output gave no protection from OH (r = 0.077) and did not correlate with blood pressure (r = 0.01). Overhydration is strongly associated with the use of antihypertensive medications and the use of diuretics in this dialysis population. Obesity seems to afford some protection from OH.

Fluid overload in hemodialysis patients: a cross-sectional study to determine its association with cardiac biomarkers and nutritional status

“…A recent study in 79 dialysis patients aiming at a reduction of blood pressure and antihypertensive medication, yielded interesting results with regard to a lower percentage of body fat in fluid overloaded dialysis patients [37]. These findings are in accordance with our results enforcing the view that underweight patients are more susceptible to fluid overload, whereas adipose patients tend to be in an underhydrated condition.…”

Brain Natriuretic Peptide and Body Fluid Composition in Patients with Chronic Kidney Disease: A Cross-Sectional Study to Evaluate the Relationship between Volume Overload and Malnutrition

“…Previous studies using bioimpedance analysis showed that overhydration is prevalent in leaner patients undergoing dialysis therapy [3,20]. Overhydration might be less apparent in obese patients [21,22]. Malnutrition-inflammation complex syndrome in those patients may partly explain the existence of the ‘obesity paradox'.…”

Fatores associados ao diagnóstico risco de volume de líquidos deficiente em pacientes em hemodiálise

“…Tal fato pode repercutir na baixa adesão ao regime terapêutico, visto que a escolaridade deficiente pode dificultar a compreensão acerca do processo de saúde-doença, além do entendimento do tratamento a ser instituído, o qual requer intervenções específi-cas, complexas, e cuja obediência é fundamental à sua eficácia. Outrossim, o cumprimento do regime terapêutico é crucial na determinação da sobrevida desses pacientes, tendo em vista as complicações tanto da sobrecarga hídrica, como as repercussões negativas da retirada excessiva de líquidos (10)(11)14).…”

“…Desse modo, em pacientes com maior IMC foi detectada a menor ocorrência da sobrecarga de volume de líquidos. Em contrapartida, um índice de massa corporal inferior é conhecido por ser fortemente associado com o aumento da mortalidade na população em hemodiálise e particularmente naqueles com sobrecarga do volume de líquidos (11,14,19).…”