Olfactory loss after head and neck cancer radiation therapy.

BACKGROUND: A reduced sense of smell may be one explanation for why patients with cancer in the ear, nose and throat (ENT) region who are treated with radiation therapy lose weight. The purpose of this study was to investigate whether radiation therapy has a negative effect on olfactory function and, if so, whether this effect is dose-related. METHODOLOGY: Seventy-one patients were tested using odour-detection sensitivity and olfactory identification tests before radiation therapy and 20 months after it. RESULTS: Patients who received radiation close to the olfactory organ showed a reduced sense of smell, in both tests. A multiple regression analysis showed that the radiation dose was related to decline in the olfactory function, while age, sex, chemotherapy and interactions between these variables were not. CONCLUSION: Radiation therapy can damage olfactory cells.

Prevalence and risk factors for self-reported odour intolerance: the Skövde population-based study.

OBJECTIVES: The present study was performed to determine the prevalence of odour intolerance in adults with respect to both self-reported general intolerance and affective and behavioural consequences. Furthermore, we aimed to relate odour intolerance to explanatory variables and risk factors. METHOD: This is a cross-sectional, population-based epidemiological study. A random sample of 1900 inhabitants from the age of 20, stratified for age and gender, were recruited. Subjects were invited for clinical examinations that included questions about general odour intolerance, respiratory symptoms and smoking habits, as well as a smell identification test. The chemical sensitivity scale for sensory hyperreactivity (CSS-SHR) was used to quantify affective and behavioural consequences. RESULTS: In total 1387 volunteers (73% of the sample) were investigated. The overall prevalence of self-reported general odour intolerance was 33% (95% confidence interval (CI): 30-36%), with problems mainly from the upper respiratory tract. The prevalence of affective and behavioural consequences of odour intolerance (CSS-SHR score > or =43) was 19% (95% CI: 15-22%). The risk for the latter condition was increased in women compared with men (odds ratio = 2.3: 95% CI: 1.5-3.6), but no increased risk was found related to current smoking or impaired sense of smell. CONCLUSION: This study demonstrates that intolerance to odours is a widespread problem in society, and that it is about twice as common in women than in men.

Clinical relevance of nasal polyps in individuals recruited from a general population-based study.

OBJECTIVE: To compare the clinical presentations of individuals with nasal polyps detected by endoscopy in a general population sample with those of patients with nasal polyp disease seeking medical attention. MATERIAL AND METHODS: A total of 38 individuals with nasal polyps from a population-based sample were compared with 38 matched controls and a third group consisting of 44 patients who presented to an outpatient clinic with symptoms and diagnosed nasal polyps Upper and lower airway symptoms were registered. Polyp size, peak nasal inspiratory flow (PNIF), olfactory function and health-related quality of life were measured. RESULTS: Compared with the individuals with nasal polyps in the population sample, patients actively seeking medical care for nasal polyposis experienced more symptoms of nasal blockage and an impaired sense of smell, and had more extensive polyps and reduced PNIF. There were equal frequencies of asthma symptoms in these two groups. Compared with the controls, the individuals with nasal polyps in the population sample had a greater frequency of asthma symptoms and aspirin intolerance and also experienced an impaired sense of smell. CONCLUSION: Nasal polyps alone, as seen occasionally, are indicative of airway disease involving the upper and lower respiratory tracts.

A Scandinavian adaptation of the Multi-Clinic Smell and Taste Questionnaire: evaluation of questions about olfaction.

OBJECTIVE: A Scandinavian adaptation of the Multi-Clinic Smell and Taste Questionnaire (MCSTQ-Sc) was evaluated with respect to comprehension and test-retest reliability for responses to questions about olfactory dysfunction (abnormal sensitivity, parosmia and phantosmia) and related questions about medical history and consequences of olfactory dysfunction. MATERIAL AND METHODS: Comprehension was evaluated in a first study in 20 patients with chief complaints of olfactory dysfunction by comparing questionnaire- and interview-based responses. Test-retest reliability was evaluated in a second study in 30 other patients with olfactory complaints. RESULTS: Data from the two studies suggest that the vast majority of the questions evaluated from the MCSTQ-Sc are comprehensible and generate responses with very good reliability. Distinct exceptions were poor agreement between the questionnaire- and interview-based responses for questions about the number of cigarettes smoked and the pleasantness and typical episode length of phantosmia; the test-retest reliability regarding the nostril side of phantosmia also showed poor agreement. The results suggest the importance of probing these areas further in the clinical interview. CONCLUSION: The findings imply that, with a few caveats, the MCSTQ-Sc is a useful tool for the clinical assessment of olfactory dysfunction and its consequences.

The Scandinavian Odor-Identification Test: development, reliability, validity and normative data.

The Scandinavian Odor-Identification Test (SOIT) was developed to address the need for a culturally valid odor-identification test for clinical use on the Scandinavian population that (i) has good ability to generalize performance to olfactory status, (ii) assesses olfactory and trigeminal function separately, (iii) requires only limited cognitive demands, (iv) has normative data and good sensitivity and specificity, and (v) is fast, easy to administer and inexpensive. Sixteen odorous test stimuli were selected that were relatively identifiable, familiar, strong in intensity and pleasant according to healthy participants. Four response alternatives were then selected for each test stimulus based on a confusion matrix of identification rates obtained from healthy participants, in a manner that controlled for task difficulty. Results on the SOIT from healthy persons and hyposmic patients showed satisfactory test-retest reliability, split-half reliability and validity. Cut-off scores for olfactory diagnosis (normosmia, hyposmia, anosmia) based on normative data obtained from 171 healthy persons showed a satisfactory sensitivity and specificity of the SOIT. Assessment of 22 anosmic patients with the SOIT revealed that three of the test stimuli were significant trigeminal stimulants.