The association between olfactory and gustatory dysfunction and chronic kidney disease

Abstract

Background Olfactory and gustatory changes may contribute to poor appetite and food aversion in chronic kidney disease (CKD), though the prevalence of olfactory and gustatory dysfunction is not known in the CKD population. Methods We conducted a cross-sectional study among 3527 US adults aged ≥40 years old in the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2014. We measured the prevalence of olfactory and gustatory dysfunction among patients with CKD defined as eGFR < 60 ml/min/1.73m2 using the “scratch and sniff” NHANES Pocket Smell Test and quinine whole-mouth test. We also examined the association between CKD and olfactory/gustatory dysfunction, and nutritional markers. Results The prevalence of olfactory dysfunction was 30% among CKD and 15% among non-CKD (p < 0.001). The prevalence of gustatory dysfunction was 13% among CKD and 17% among non-CKD (p = 0.10). After adjusting for confounders, CKD was significantly associated with olfactory dysfunction (OR = 1.47, 95% CI [1.07, 2.01]; p = 0.02) but not gustatory dysfunction (OR = 1.76, 95%CI [0.99, 3.11]; p = 0.05). Among the CKD population, the odds of olfactory dysfunction was 72% higher for every 10 kg decrease in grip strength (OR = 1.72, 95% CI [1.39, 2.13]; adjusted p = 0.005). Conclusion CKD was associated with higher odds of olfactory but not gustatory dysfunction. Olfactory dysfunction was associated with lower grip strength among those with CKD. Screening and early intervening on olfactory dysfunction among CKD may preserve muscle strength and improve nutritional status in this vulnerable population.

Relationship between altered taste and smell with malnutrition among hemodialysis patients

“…A review of the literature showed that despite differences, there was consistently a high prevalence of altered taste (31%-80%) and smell (30%-56%) among hemodialysis patients. [4][5][6] The reason for the differences between these prevalences can be explained by the different measurement methods used in the evaluation of altered taste and smell in studies (visual analogue scale, electrogustometry, taste strips, sniffing sticks, multiple liquid stimuli, etc.). In this study, the TSDQ, which has been validated and found reliable in hemodialysis patients, was used.…”

“…The combination of these symptoms can lead to malnutrition. 5 In a review of the literature, three studies were found on altered taste and the nutritional status of hemodialysis patients. 2,32,33 These studies showed a high prevalence of an altered taste and a significant association between altered taste, upper gastrointestinal symptoms (nausea, vomiting, anorexia, dry mouth, and pain), and malnutrition.…”

“…In the study, it was determined that nearly half of the hemodialysis patients experienced altered taste (40.27%) and smell (45.64%). A review of the literature showed that despite differences, there was consistently a high prevalence of altered taste (31%–80%) and smell (30%–56%) among hemodialysis patients 4–6 . The reason for the differences between these prevalences can be explained by the different measurement methods used in the evaluation of altered taste and smell in studies (visual analogue scale, electrogustometry, taste strips, sniffing sticks, multiple liquid stimuli, etc.).…”

“…3 The prevalence of altered taste and smell in hemodialysis patients ranges from 30% to 80%. [4][5][6] Altered smell and taste in hemodialysis patients have been attributed to increased urea, trimethylamine levels, and decreased serum zinc levels, [7][8][9] and have been associated with loss of appetite, low food consumption, inadequate or inappropriate food choices, poor adherence to dietary treatments, and malnutrition in various patient groups. [10][11][12] However, there is not enough information to understand the effects of altered taste and smell on patient outcomes in end-stage renal disease.…”

“…Although these symptoms are considered the most distressing, their clinical evaluation and management are usually overlooked 3 . The prevalence of altered taste and smell in hemodialysis patients ranges from 30% to 80% 4–6 …”