Olfactory function in patients undergoing hemodialysis as assessed by Sniffin' Sticks testing

Area of Science:

• Nephrology
• Neuroscience
• Otolaryngology

Background:

• Olfactory dysfunction is a common complication in patients with chronic kidney disease.
• Hemodialysis is a life-sustaining treatment for end-stage renal disease, but its effects on sensory functions are not fully understood.

Purpose of the Study:

• To evaluate olfactory function in patients undergoing hemodialysis.
• To compare olfactory function between hemodialysis patients and healthy controls.

Main Methods:

• The study included 56 hemodialysis patients and 54 healthy controls.
• Olfactory function was assessed using the Sniffin' Sticks test, which measures the ability to identify 12 different odors.
• Anosmia was defined as a score below 6, hyposmia as scores from 7 to 10, and normal olfaction as a score of 11 or higher.

Main Results:

• Hemodialysis patients had significantly lower olfactory scores (9.12±2.77) compared to controls (10.72±1.94).
• Olfactory impairment, including anosmia (12.5%) and hyposmia (50.0%), was present in 62.5% of hemodialysis patients.
• No significant correlation was found between olfactory scores and age, sex, or duration of renal failure in the hemodialysis group.

Conclusions:

• Hemodialysis is associated with a significant decrease in olfactory function.
• A high prevalence of olfactory impairment exists in patients on hemodialysis.
• Further research into the neuroplasticity of olfactory neurons may inform potential interventions, such as renal transplantation, to improve smell.