Usefulness of the BAST-24 smell and taste test in the study of diabetic patients: a new approach to the determination of renal function.

CONCLUSION: A reduction in the percentage of correct responses in the olfactory test indirectly indicated increased albuminuria and worse glomerular filtration rate (GFR) in diabetic patients. The olfactory function test is an indirect indicator of early microvascular complications in diabetic patients.

OBJECTIVES: Diabetes mellitus is a highly prevalent disease that causes numerous complications. The aim of this study was to determine whether olfactory and taste sensations are related to renal failure in diabetic patients.

METHODS: We studied 61 patients diagnosed with diabetes mellitus, mean age = 65.9 years (SD = 16.8), 54.1% male. We evaluated olfactory and taste sensations by determining the capacity of detection, identification and percentage of correct responses of the 29 components of the Barcelona Smell-taste Test-24 (BAST-24). We determined the relationship between these results and glycosylated haemoglobin (HbA1c), creatinine, albumin/creatinine, albuminuria and GFR (normal = GFR ≥ 60 ml/min/1.73 m(2); impaired renal function = GFR < 60 ml/min/1.73 m(2)).

RESULTS: There was no significant relationship between HbA1c and olfactory and taste sensations. There was a significant relationship between the percentage of correct responses and albuminuria (p = 0.03) and between identification of odours through the olfactory nerve and GFR (p = 0.029), and the percentage of correct responses and GFR (p = 0.03). There was no significant relationship between taste and renal failure.