Olfactory and Gustatory Function in Patients with Multiple Sclerosis

Abstract

The olfactory function (OF) and gustatory function in patients with multiple sclerosis (MS) can be limited. We performed the testing of orthonasal (Threshold Discrimination Identification [TDI] score with Sniffin' Sticks) and retronasal (Taste Powder) OF and gustatory function (Taste Strips; Burghart, Wedel, Germany) in patients diagnosed with MS and healthy controls matching in age, sex, and smoking habits. Eight of 16 MS patients (50%) displayed hyposmia (TDI score, 28.75 ± 1.28; p = 0.06); the identification subtest significantly was restricted (12.63 ± 1.67; p = 0.001). Four of 16 MS patients (25%) had limited retronasal OF with a Taste Powder score of 4.5 ± 1.29. The gustatory function in 19% of MS patients was significantly limited (Taste Strip score, 5.33 ± 2.52; p = 0.02). Patients who estimated their ability to smell as diminished performed more poorly on retronasal OF testing (r =0.657; p = 0.046). This study confirms the incidence of olfactory disorder in MS patients that has been reported in the literature. Interestingly, a significant correlation between orthonasal and retronasal OF testing was not shown. A higher incidence of gustatory dysfunction was shown and might serve as another potential marker for this disease.