B-type (brain) natriuretic peptide and pruritus in hemodialysis patients

Abstract

Introduction and objective:While pruritus is a common complication in hemodialysis patients, the pathophysiological mechanisms remain obscure. Recently, B-type (brain) natriuretic peptide (BNP) has been defined as an itch-selective neuropeptide in pruriceptive neurons in mice, and higher serum levels of BNP are frequently observed in hemodialysis patients. The objective of the present study was to evaluate the role of serum BNP in pruritus in patients undergoing hemodialysis. Patients and methods:The current cross-sectional study was performed on 43 patients undergoing maintenance hemodialysis. A visual analog scale (VAS) measuring the general severity of pruritus (values from 0 to 10, with higher values indicating more severe pruritus) in daytime and at night was self-reported by patients. Each patient's background and laboratory tests, including serum BNP in the post-hemodialysis period, were collected. The correlation between VAS and clinical parameters was evaluated. Results: Both daytime and nighttime VAS scores in diabetic patients were significantly less than those in nondiabetic patients. Multiple regression analysis revealed that pruritus in daytime was worsened by serum BNP (β=2.0, t=2.4, P=0.03), calcium (β=4.4, t=5.2, P,0.0001), and β 2 -microglobulin (β=2.0, t=3.0, P=0.007), while it was eased by age (β=-2.2, t=-3.2, P=0.0004). Nocturnal pruritus was severe in nondiabetic patients (β=1.7, t=3.8, P=0.0005) and weakened by the total iron binding capacity (β=-2.9, t=-3.1, P=0.004). Conclusion: It is suggested that a higher level of serum BNP increases the pruritus of hemodialysis patients in daytime and that diabetic patients are less sensitive to itch, especially at nighttime.

Uremic pruritus and long-term morbidities in the dialysis population

“…Therefore, the increase of BNP with volume overload may have a role in itching transmission. Clinically, Shimizu et al reported an association between elevated BNP and the severity of pruritus [ 41 ]. This provides a possible link between pruritus and volume overload in dialysis patients.…”

Spinal Functions of B-Type Natriuretic Peptide, Gastrin-Releasing Peptide, and Their Cognate Receptors for Regulating Itch in Mice

“…A recent study reported that BNP-NPRA signaling is a key mechanism of itch transmission in the mouse spinal cord (Mishra and Hoon, 2013). In addition, an increased level of serum BNP was found to be associated with the degree of pruritus in hemodialysis patients (Shimizu et al, 2014). Anatomic and pharmacological studies have demonstrated that GRP-GRPR system acts downstream of the BNP-NPRA signaling in the pruriceptive circuit as an itchselective regulation by BNP (Mishra and Hoon, 2013).…”

Uremic Pruritus is Associated with Two-Year Cardiovascular Mortality in Long Term Hemodialysis Patients

“…BNP knocked out mice lose almost all behavioral responses to itchinducing agents [26]. Shimizu et al also demonstrated that serum brain BNP associates with the pruritus of hemodialysis patients [27]. Uremic pruritus might be a consequence of elevation of BNP induced by left ventricular pressure and volume overload due to salt and water retention and anemia, and increased blood volume and left ventricular end diastolic dysfunction caused by the arteriovenous vascular access in hemodialysis patients [28][29][30].…”