ENT JOURNAL READING: Predictors of Olfactory Dysfunction in Patients With Chronic Rhinosinusitis

1. ENT JOURNAL READING:Predictors of Olfactory Dysfunction in Patients With Chronic Rhinosinusitis Laryngoscope, 118:2225–2230, 2008 Supervisor 侯友益 R 陳芝瑜

2. INTRODUCTION • Chronic rhinosinusitis (CRS) is a common cause of olfactory dysfunction.(14%-30%) • Etiology : Multifactorial • Conductive mechanisms • Mechanical obstruction by nasal polyposis and respiratory mucosal edema • Sensorineural mechanisms • Direct inflammation of the olfactory neuroepithelium • clinical response to systemic corticosteroids

3. INTRODUCTION • Objectives: • To measure the prevalence of and identify clinical characteristics associated with poor olfactory function in a patients with chronic rhinosinusitis (CRS). • help to inform clinicians which patients are at highest risk for olfactory dysfunction and in need of patient safety counseling and further treatment.

4. INTRODUCTION • Study Design • Multi-institutional, cross sectional analysis

5. MATERIALS AND METHODS • Study Population and Data Collection • 3-year period, 3 tertiary care centers • N= 367, age >=18 years • All patients had a diagnosis of CRS based on the Rhinosinusitis Task Force criteria • Variables included: • age, gender, current tobacco use, prior sinus surgery, nasal polyposis, asthma, allergic rhinitis confirmed by allergy testing, acetylsalicylic acid intolerance, septal deviation, and inferior turbinate hypertrophy

6. MATERIALS AND METHODS • Study Population and Data Collection • Exclude: • younger than 18 years • immunodeficiency (n=5) • autoimmune disease (n=8) • and/or cystic fibrosis (n =12) • olfactory test scores consistent with malingering (score<=5) (n= 4)

7. MATERIALS AND METHODS • Measurement of Olfactory Function • Smell Identification Test (SIT): • total score: 0–40(40 question forced-choice test) • high test-retest reliability (r >0.90)

8. MATERIALS AND METHODS • Statistical Analyses • SPSS v15.0 statistical software • Data were analyzed using univariate and multivariate analyses.

9. RESULTS

12. Acetylsalicylic acid intolerance, allergic rhinitis, and/or prior sinus surgery: neither increased nor decreased risk of olfactory dysfunction

13. DISCUSSION

14. Associated with olfactory dysfunction: • Age> 65 years • Nasal polyposis • Asthma • Smoking • Notsignificantly associated: • Aspirin intolerance • Allergic rhinitis • History of prior sinus surgery • Gender • Normal olfactory function • septal deviation • inferior turbinate hypertrophy

15. Chronic rhinosinusitis V.S olfactory dysfunction • Conductive disorder? • Sensorineural process? • Clinical cofactors?

16. Age • Rats • increased proapoptotic gene expression • increased olfactory receptor neuron cell death • Patients • Inflammation in the olfactory mucosa may inhibit olfactory neurogenesis. • “two-hit” fashion

17. Smoking • Cumulative dose of smoking and time since last cigarette • Frye et al. • current smokers are 1.9 times as likely to have olfactory dysfunction as never smokers • Bias • quantity of cigarettes / time since last cigarette

18. Nasal polyposis • Obstruction of the airway • Degenerative changes • Recurrent infections • Scarring • Chronic nasal medication use • Perry and Kountakis, Vento et al

19. Asthma • Systemic inflammatory responses of the upper and the lower airway. • May affect the olfactory cleft

20. Allergic rhinitis • High flow areas of the nasal airway, such as the inferior turbinate and middle meatus • Our findings suggest that lower flow areas, such as the olfactory cleft, are less affected • Simola and Malmberg • nonallergic rhinitis patients had a poorer sense of smell than patients with seasonal or perennial allergic rhinitis

21. History of prior sinus surgery • Proposed to cause olfactory injury • direct injury to the olfactory epithelium, modification of airflow… • Adjusted for in the multivariate logistic regression model • History of surgery for nasal polyposis was associated with poor olfactory function but a history of surgery for chronic maxillary sinusitis was not. • Underlying medical comorbidity (nasal polyposis) contributed to the olfactory dysfunction rather than the surgery.

22. Aspirin intolerant • Patients with aspirin intolerance frequently suffer from olfactory dysfunction although we were unable to detect it. • Relatively small number patients.

23. Septal deviation and inferior turbinate hypertrophy • Both diagnoses were determined by the clinician, they are subjective in nature and susceptible to potential bias.

24. CONCLUSION • Associated with olfactory dysfunction: • Age> 65 years • Nasal polyposis • Asthma • Smoking • Not significantly associated: • Aspirin intolerance • Allergic rhinitis • History of prior sinus surgery • Gender • Normal olfactory function • septal deviation • inferior turbinate hypertrophy

25. THANK YOU!