Olfactory Dysfunctions and Chronic Kidney Disease: A Scoping Review

Abstract

Chronic kidney disease (CKD) represents a significant global public health challenge. Among the various clinical complications associated with CKD, olfactory dysfunction has been identified as a factor that substantially affects the quality of life of patients. This study aims to systematically explore the prevalence, implications, and therapeutic avenues of anosmia in CKD patients. This scoping review utilized the Arksey and O'Malley framework, incorporating the Joanna Briggs Institute methodology, and followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidelines. The research question, formulated using the PIO framework, guided a thorough search of databases PubMed/Medline, Embase, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Cochrane Library and gray literature sources. Eligibility criteria focused on studies involving CKD patients with olfactory dysfunctions. From an initial pool of 832 articles, 17 studies met the criteria, providing insights into olfactory alterations in 4,025 CKD patients. The data that have been reported, define that 55,34% of the sample experienced olfactory changes and the 8.5% experienced anosmia. This review revealed a complex interplay of factors contributing to olfactory alterations, including uremic toxins, dialysis procedures, electrolyte imbalances, and malnutrition. Findings suggested the potential recovery of olfactory function following kidney transplantation. Various assessment tools were utilized, with the University of Pennsylvania Smell Identification Test and Sniffin' Sticks emerging as the primary instruments. The observed variability in findings highlights the need for continued research to understand the mechanisms, enhance therapies, and improve quality of life for CKD patients with olfactory dysfunctions. Future studies should employ standardized methods, explore new assessment tools, and prioritize longitudinal assessments to advance our understanding and management of olfactory dysfunctions in this population.

Keywords: Anosmia; Chronic Kidney Disease; Olfactory Dysfuntion.