SPLTRAK Abstract Submission
Olfactory function after mild traumatic brain injury in children – a longitudinal study
Theresa Thieme & Valentin Schriever
Abteilung Neuropädiatrie, Dresden, Germany

Aim: An association between traumatic brain injury (TBI) and olfactory dysfunction has been described in previous studies. However, predictive markers for olfactory dysfunction after TBI in children are not well examined. Aim of the study was to examine olfactory function after mild TBI in a longitudinal study design in children and to identify predictive markers for olfactory dysfunction after TBI. Material and methods: A total of 151 children (75 patients after mild TBI, 76 healthy children as control group (age and sex matched)), age 6-16 years were included. Patients were fist tested on average at 1.8±0.9 days after TBI (T1). The follow-up testing was conducted after 12 months (T2). Olfactory function was assessed using an olfactory threshold and the “U-Sniff” odor identification test.    Results: Overall patients scored worse on olfactory threshold test compared to controls (p<0.01). The difference just misted significance at T1 testing (p=0.051) and still showed a strong trend at the one-year follow-up (T2) (p=0.088). No significant difference between patients and controls was found regarding odor identification. 47% of patients scored below the 10th percentile on olfactory threshold at T1 compared to 16% of the control group (χ2=6.51, p=0.01). This difference showed still a strong trend at T2 (χ2=3.22, p=0.07). None of the TBI symptoms (emesis, loss of consciousness amnesia, location of TBI) showed to have a significant predictive value regarding olfactory dysfunction at T1 or T2. Conclusion: Even mild TBI showed to be associated with olfactory dysfunction in children. Although olfactory function improved in patients, the difference was still measurable after one year. No predictive marker for developing olfactory dysfunction after mild TBI could be identified.