Clinical influencing factors affecting pulmonary hypertension in hemodialysis patients

The fluid status and rate of blood flow through the arteriovenous fistula (AVF) are two important factors affecting hemodynamic in hemodialysis patients; however, their effects on pulmonary hypertension have rarely been studied. Hence, we aimed to evaluate the effects of these factors in hemodialysis patients with pulmonary hypertension.

This single-center cross-sectional survey included 219 maintenance hemodialysis patients (139 [63.5%] male). The prevalence of pulmonary hypertension was 13.6% (30 of 219). Pulmonary artery pressure was measured by echocardiography, fluid status was measured objectively using bioimpedance spectroscopy, and blood flow rate in the AVF (Qa) was determined using Doppler ultrasound.

The overall mean overhydration before hemodialysis was 1.5 L (range, 0.6-2.8 L). The mean overhydration in patients with and without pulmonary hypertension was 3.6 L (range, 2.3-4.6 L) and 1.4 L (range, 0.6-2.4 L), respectively (p < 0.001). The overall mean Qa was 780 mL/min (range, 570-1,015.5 mL/min). The mean Qa of patients with and without pulmonary hypertension was 672 mL/min (range, 505.7-982.2 mL/min) and 790 mL/min (range, 591-1,026 mL/min), respectively (p = 0.27). Overhydration (odds ratio [OR], 1.46; 95% confidence interval [CI], 1.08-1.97; p = 0.01), N-terminal prohormone of brain natriuretic peptide (NT-proBNP; OR, 1.36; 95% CI, 1.09-1.71; p = 0.007), and left atrial diameter (OR, 1.14; 95% CI, 1.01-1.28; p = 0.03) were risk factors.

Pulmonary hypertension is strongly associated with overhydration, NT-proBNP, and left atrial diameter in hemodialysis patients.