Olfactory and gustatory impairment in systemic cardiac amyloidosis: a prospective case-control study

Amyloidosis is a multi-systemic disease with a poor prognosis. We hypothesized that amyloid proteins could deposit along the olfactory and gustatory systems and cause olfactory and gustatory impairment. The objective was to assess the prevalence of olfactory and gustatory disorders in a population of patients diagnosed with cardiac amyloidosis (CA).

CA patients from three amyloid subtypes (hereditary or wild-type transthyretin (ATTRv and ATTRwt) and light chain (AL)) and a control group of patients with chronic non-amyloidotic heart failure were enrolled prospectively in this case-control study. Nasal endoscopy, olfactory and gustatory questionnaires, "shortened Sniffin' Sticks" test (sSST) and Taste Band Strips test were performed.

Thirty-eight CA patients (mean age of 80.8 +/- 8.6 years; 65.8 % males) and 13 control patients (mean age of 63.2 +/- 16.4 years; 53.8 % males) were included. The mean total score on the sSST for CA patients was significantly lower than that of the control group (15.4±6.2 vs 20.3 +/- 5.3, respectively, p = 0.02). Five out of 38 (13.1 %) CA patients were complaining of dysosmia compared to 3/13 (23.1 %) patients in the control group. Taste impairment was noted in 24/37 (64.9 %) CA patients vs 6/12 (50 %) patients in the control group (p > 0.05).

This study comparing olfactory function of CA patients to chronic non-amyloidotic heart failure patients found that CA patients had significantly more olfactory impairments. Olfactory impairments could therefore be a new "red flag" that may help in early diagnosis and treatment of CA.