ABSTRACT
Objective: To assess the frequency and factors associated with posttraumatic olfactory dysfunction, including anosmia, in a follow-up of patients with moderate and severe traumatic brain injury (TBI).
Methods: The setting was a cross-sectional study of patients that were consecutively included in the Trondheim TBI database, comprising injury-related variables. Eligible participants 18–65 years were contacted 9–104 months post trauma and asked olfactory-related questions. Those reporting possible posttraumatic change of olfaction were invited to further examination using the Sniffin’ Sticks panel.
Results: Of 211 eligible participants, 182 (86.3%) took part in telephone interviews and 25(13.7%) were diagnosed with olfactory dysfunction. 60% of these, or 8.2% of all participants, had anosmia. In age-adjusted logistic regression analyses, fall (OR 2.5, 95% CI 1.0–6.2), skull base fracture (OR 2.9, 95% CI 1.2–7.1) and cortical contusion(s) (OR 6.0, 95% CI 2.1–17.3) were associated with olfactory dysfunction. In an analysis of anosmia, fall (OR 3.4, 95% CI 1.1–10.6) and cortical contusion(s) (OR 19.7, 95% CI 2.5-156.0) were associated with the outcome.
Conclusion: Of the study participants 13.7% had olfactory dysfunction and 8.2% had anosmia. Higher age, trauma caused by fall and CT displaying skull base fracture and cortical contusion(s) were related to olfactory dysfunction.
Acknowledgments
We thank the Clinical Research Facility at St. Olav‘s University Hospital for assistance with the telephone screening and olfactory testing. We thank Ingrid Haavde Strand, Susan Frances Deane and Kjell Arne Kvistad from the Clinic of Radiology and Nuclear Medicine at St. Olav’s University Hospital, for investigation of the CT scans.