Pulmonary hypertension in patients with chronic renal failure - Role of parathyroid hormone and pulmonary artery calcifications

Rationale: The aim of this work was to study the association of pulmonary hypertension (PH) with pulmonary artery calcifications (PACs) and hyperparathyroidism in patients with chronic renal failure (CRF) receiving regular hemodialysis. Background: Scarce data are available regarding the prevalence and the predictors of PH in patients with CRF. Abnormal Tc-99m diphosphonate lung uptake was reported in these patients, suggesting a role of PACs. Methods: We studied 51 patients (28 men and 23 women) with end-stage renal disease, who were receiving regular hemodialysis. Patients underwent two-dimensional, Doppler echocardiographic imaging. Laboratory investigations included BUN, serum creatinine, calcium, phosphorus, alkaline phosphatase, and intact molecule parathormone. PH was defined as pulmonary artery systolic pressure > 35 mm Hg as determined by Doppler echocardiographic evaluation. Results: PH was detected in 15 patients (29%). Women had a higher prevalence of PH (48% vs 14%, p = 0.01). There was no significant differences between patients with PH and those without PH with regards to age, duration of dialysis, serum calcium (9.6 +/- 2 mg1dL vs 10 +/- 2 mg/dL), phosphorus (6 +/- 1.4 mg/L vs 6.2 +/- 1.9 mg/L), alkaline phosphatase (609 +/- 768 U/L vs 473 +/- 574 U/L), parathyroid hormone (PTH) [420 +/- 512 pg/mL vs 354 +/- 519 pg/mL] or the prevalence of an abnormal Tc-99m diphosphate lung scan result (60% vs 73%, respectively [+/- SD]). Conclusions: This study demonstrated that 29% of patients with CRF receiving regular hemodialysis have PH. The presence of PH was not related to the level of PTH or the severity of other metabolic abnormalities. There was no relation between PH and the presence or the severity of PAC. PH is detected more frequently in women. This study does not support a role of secondary hyperparathyroidism and subsequent PAC as the etiology of PH in patients with CRF.