Pulmonary hypertension in patients with stage 1-3 chronic kidney disease

Pulmonary hypertension (PH) secondary to chronic kidney disease (CKD) is common, but in stages 1-3 CKD patients, it remains unclear. We sought to evaluate the prevalence of PH and elucidate the possible pathogenesis in Chinese patients with early stage kidney disease. Doppler-estimated pulmonary systolic artery pressure (PASP) was measured in 101 CKD patients with glomerular filtration rate (GFR) >= 60 mL/min/1.73 m(2) and 27 CKD patients with GFR < 60 mL/min/1.73 m(2). Echocardiographic parameters, plasma brain natriuretic peptide (BNP), and baseline characteristics of patients were recorded. PH was defined as a PASP >= 35 mmHg. PH prevalence was 23.76% (24/101) in GFR >= 60 mL/min/1.73 m(2) group and 48.15% (13/27) in GFR < 60 mL/min/1.73 m(2) group, P < 0.05. Mean lnBNP was 4.93 +/- 1.60 pg/mL in 37 cases with PH and 2.89 +/- 1.29 pg/mL in those without, P < 0.01. Left atrial diameter (LA) showed deviation between patients with (43.94 +/- 5.81 mm) and without PH (37.76 +/- 7.48 mm), P < 0.01. GFR declined significantly in PH group (44.10 +/- 22.90 mL/min/1.73 m(2)) compared to non-PH group (75.59 +/- 31.62 mL/min/1.73 m(2)), P < 0.01. lnBNP, LA and GFR were independent determinants (r = 0.651, 0.595, -0.488, P < 0.01) of PASP. PH is prevalent among stage 1-3 CKD patients in China. Doppler-estimated PASP is strongly associated with lnBNP, enlarged LA and GFR. Monitoring PASP, plasma BNP and evaluation renal function may help to detect and prevent severe PH in CKD.