Gustatory and olfactory sensitivity in patients with anorexia and bulimia in the course of treatment.

BACKGROUND: The majority of studies on taste and smell in eating disorders have revealed several alterations of olfactory or gustatory functions. Aim of this prospective study was to employ detailed olfactory and gustatory testing in female subjects of three homogenous groups - anorexia nervosa, bulimia nervosa and healthy controls - and to look at the effects of treatment on these measures.

METHODS: Sixteen hospitalized female patients with anorexia (restricting type, mean age [M]=24.5 years), 24 female patients with bulimia (purging type, M=24.3 years) as well as 23 healthy controls (M=24.5 years) received olfactory ("Sniffin' Sticks") and gustatory testing ("Taste Strips"). Group differences in olfactory and gustatory sensitivity, body mass index (BMI), the Beck depression inventory, the eating attitudes test (EAT), and the influence of therapy on gustatory and olfactory function were investigated.

RESULTS: (1) Group differences were present for odor discrimination and overall olfactory function with anorexic patients having the lowest scores. (2) Regarding taste function, controls scored higher than patients with anorexia. (3) At admission small but significant correlations were found between overall olfactory function and body weight (r(63)=0.35), BMI (r(63) = 0.37), and EAT score (r(63) = -0.27). Similarly, (4) the taste test score correlated significantly with body weight (r(63)= 0.48), and BMI (r(63) = 0.45). Finally, (5) at discharge overall olfactory and gustatory function were significantly higher compared to admission in anorexic patients.

CONCLUSIONS: As compared to healthy controls and bulimic patients our results show lowered olfactory and gustatory sensitivities in anorexic patients that improved with increasing BMI and decreasing eating pathology in the course of treatment.