BRONCHIAL RESPONSIVENESS IN PATIENTS ON REGULAR HEMODIALYSIS-TREATMENT OF VERY LONG-DURATION

Several mechanisms (trapping of neutrophils, increased extravascular l ung water, left ventricular hypertrophy, metastatic lung calcification , and iron deposition) may impair pulmonary function and alter bronchi al responsiveness in patients on long-term regular dialysis treatment (RDT), but no studies have been published concerning patients on RDT f or a very long time. To assess bronchial reactivity, a methacholine in halation test was performed 2 to 24 hours after a dialysis session in 19 patients with RDT duration of almost 20 years (221 +/- 26 months) ( group 1) and in 14 patients on RDT for a shorter time (24 +/- 22 month s) (group 2); all patients had normal standard pulmonary function test results (group 1: forced vital capacity, 95% +/- 13% and forced expir atory volume in one second [FEV(1)]: 97% +/- 17%; group 2: forced vita l capacity, 108% +/- 11% and FEV(1), 108% +/- 9% of expected values). The methacholine provocation dose causing a 20% decrease in FEV(1) was significantly lower than normal in seven (37%) group 1 patients and o nly in one (7%) group 2 patient; this difference was statistically sig nificant (P = 0.049). There were no correlations between bronchial hyp erresponsiveness and interdialysis weight gain, left ventricular hyper trophy, diastolic dysfunction expressed as the ratio between early dia stolic filling and filling during atrial contraction, secondary hyperp arathyroidism, and iron overload. Therefore, branchial hyperresponsive ness is present in a substantial percentage of patients on RDT of very long duration, but the cause is unknown. (C) 1994 by the National Kid ney Foundation, Inc.