Hazardous events associated with impaired olfactory function

Objective: To evaluate the risk of olfactory-related hazardous events in patients with impaired olfactory function. Design: Retrospective cohort study. Setting: A university-based clinic for smell and taste disorders. Patients: A total of 445 patients who underwent olfactory testing between 1983 and 2001. Interventions: Patient interview, olfactory testing. Main Outcome Measures: (1) Frequency of olfactory-related hazardous events including cooking incidents (ie, burning pots or pans), undetected fires, undetected gas leaks, and ingestion of spoiled foods or toxic substances; (2) level of olfactory function (anosmia; severe, moderate, or mild hyposmia; or normosmia) as determined by olfactory testing. Results: Olfactory testing revealed that 76% of patients had some degree of impairment; 30% had complete anosmia. Thirty-seven percent of patients with olfactory impairment but only 19% of patients without impairment experienced at least I olfactory-related hazardous event. Of the hazardous events reported by impaired patients, cooking-related incidents were most common, representing 45%, with ingestion of spoiled food (25%), inability to detect a gas leak (23%), and inability to smell a fire (7%) reported less frequently. There was a significant correlation between frequency of hazardous events and degree of olfactory impairment (Cochran-Armitage trend test, P<.001): at least 1. hazardous event was reported by 45.2% of patients with anosmia, 34.1% with severe hyposmia, 32.8% with moderate hyposmia, 24.2% with mild hyposmia, and 19.0% of patients with with normal olfaction by testing. Conclusion: Patients with impaired olfactory function are more likely to experience olfactory-related hazardous events than those with normal olfactory function.