Distinctive Olfactory Pattern in Parkinson's Disease and Non-Neurodegenerative Causes of Hyposmia.

BACKGROUND: Olfactory dysfunction is common in Parkinson's disease (PD). The characteristics of the hyposmia in PD have not been well defined. OBJECTIVE: To characterize the pattern of the olfactory deficit in PD and in other non-neurodegenerative aetiologies of hyposmia. METHODS: We evaluated 36 PD patients, 20 patients with hyposmia secondary to acute respiratory infection (ARI), and 19 patients with hyposmia secondary to traumatic brain injury (TBI). For comparison purposes, we included a group of 15 controls age and sex matched with PD patients. PD patients were classified based on disease duration and severity in de novo PD, and PD with and without chronic levodopa-related complications. The Barcelona Smell Identification Test was applied to all participants. RESULTS: For the first cranial nerve odours, PD patients scored lower than controls on smell detection (85.28 vs. 97.67%, p = 0.006), definition (79.58 vs. 93.33%, p = 0.007), recognition (63.33 vs. 81%, p = 0.020), and forced choice (58.06 vs. 82%, p < 0.001). Compared with ARI, forced choice was significantly better in PD patients (p < 0.001), but no differences were found regarding other olfactory characteristics. TBI patients showed significantly lower scores than the other study groups in all the olfaction items. For the fifth cranial nerve odours, recognition (p = 0.003) and identification (p = 0.019) were lower in the TBI group than in the others. No differences were found among PD subgroups regarding any olfactory characteristic. CONCLUSIONS: A differential pattern of hyposmia was observed in PD patients compared to other non-neurodegenerative aetiologies. Further studies with larger samples should replicate our results.

Furthering the understanding of olfaction, prevalence of loss of smell and risk factors: a population-based survey (OLFACAT study).

OBJECTIVES: To investigate olfaction in general population, prevalence of olfactory dysfunction and related risk factors. DESIGN: Cross-sectional population-based survey, distributing four microencapsulated odorants (rose, banana, musk and gas) and two self-administered questionnaires (odour description; epidemiology/health status). SETTING: The survey was distributed to general population through a bilingual (Catalan, Spanish) newspaper in Catalonia (Spain), on December 2003. PARTICIPANTS: Newspaper readers of all ages and gender; 9348 surveys were analysed from the 10 783 returned. MAIN OUTCOME MEASURES: Characteristics of surveyed population, olfaction by age and gender, smell self-perception and smell impairment risk factors. Terms normosmia, hyposmia and anosmia were used when participants detected, recognised or identified all four, one to three or none of the odours, respectively. RESULTS: Survey profile was a 43-year-old woman with medium-high educational level, living in a city. Olfaction was considered normal in 80.6% (detection), 56% (recognition/memory) and 50.7% (identification). Prevalence of smell dysfunction was 19.4% for detection (0.3% anosmia, 19.1% hyposmia), 43.5% for recognition (0.2% anosmia, 43.3% hyposmia) and 48.8% for identification (0.8% anosmia, 48% hyposmia). Olfaction was worse (p<0.0001) in men than in women through all ages. There was a significant age-related smell detection decline however smell recognition and identification increased up to fourth decade and declined after the sixth decade of life. Risk factors for anosmia were: male gender, loss of smell history and poor olfactory self-perception for detection; low educational level, poor self-perception and pregnancy for recognition; and older age, poor self-perception and history of head trauma and loss of smell for identification. Smoking and exposure to noxious substances were mild protective factors for smell recognition. CONCLUSIONS: Sense of smell in women is better than in men suggesting a learning process during life with deterioration in older ages. Poor self-perception, history of smell loss, head trauma and pregnancy are potential risk factors for olfactory disorders.

[Olfactory alterations in allergic rhinitis to pollens and mites]. / Alteraciones olfativas en las rinitis alérgicas a pólenes y ácaros.

INTRODUCTION: In the last 80 years, the presence of allergies has increased among Europeans from 0.28% to 14.2%. Allergic rhinitis is the main presentation, rising from 18% to 40% of cases. The aim of this study is to demonstrate that allergic rhinitis due to pollen and mites has an effect on the olfactory system. MATERIAL AND METHODS: We describe the impairment of olfactory function in two groups of individuals with allergic rhinitis due to mites or pollen (n = 76; 42 with allergy to pollen [48.9%], and 34 with allergy to mites [39%]), compared with a group of healthy volunteers (n = 120). Olfactory ability was measured by the BAST-24 (Barcelona Smell Test) olfactometer comprising 20 odours tested by the forced choice method to compare the levels of odour detection (knowing if there is odour in the environment), and efficacy (identifying what was smelt). RESULTS: The results show firstly that people with allergic rhinitis have a clear, definitive, and significant impairment (P >.05) in olfactory levels; secondly, there is a tendency towards greater olfactory loss in the case of people with pollen-related allergic rhinitis than in those allergic to mites; and thirdly, the different odours are affected differently in the 2 groups. CONCLUSIONS: We propose consideration of the study of olfactory status in the assessment of patients with allergic rhinitis.

A short course of oral prednisone followed by intranasal budesonide is an effective treatment of severe nasal polyps.

BACKGROUND: Nasal polyposis is an inflammatory disease of unknown etiology. This study aimed to evaluate the effect of a short course of oral prednisone followed by intranasal budesonide on nasal symptoms, polyp size, nasal flow, and computed tomography scan. METHODS: Eighty-four patients with severe nasal polyps were included. After a steroid washout period, patients were randomized into two groups: group A (n = 63) received oral prednisone for 2 weeks and group B (n = 21) did not receive any steroid treatment. Patients from group A received intranasal budesonide for 12 weeks. RESULTS: Atopy was positive in 36.8% of patients. Blood eosinophilia was higher in asthmatic (7.2 +/- 0.7%, P < .05) than in nonasthmatic (3.0 +/- 0.4%) patients. Asthmatic patients showed higher scores on nasal obstruction and loss of smell than nonasthmatics. Oral steroids caused a significant improvement in all nasal symptoms and improved polyp size (2.1 +/- 0.1, P < .05) and nasal flow (560 +/- 35 cm/s, P < .05) compared with nontreated patients (2.8 +/- 0.1 and 270 +/- 34 cm/s, respectively). Intranasal budesonide maintained the improvement on nasal symptoms, polyp size, and nasal flow. Steroid treatment reduced the computed tomography scan score (15.4 +/- 1, P < .05) compared with before treatment (18.2 +/- 0.8). CONCLUSION: A short course of oral steroids improved all nasal symptoms, polyp size, and nasal flow, whereas intranasal steroid maintain this effect.

Barcelona Smell Test - 24 (BAST-24): validation and smell characteristics in the healthy Spanish population.

OBJECTIVES: Smell tests for clinical use have been developed in different countries, but no single test has gained general acceptance. The objectives of the study were to evaluate the smell outcomes in a Spanish population. METHODS: A prospective study on healthy volunteers (n = 120) without olfactory disturbances was performed. The volunteers were differentiated by gender, age, and smoking habit groups. We used a new olfactory test, the Barcelona Smell Test 24 (BAST-24) that consists of 24 odours scoring smell detection, identification, and forced choice. RESULTS: Volunteers showed the highest scores on smell detection for both 1st (99%) and 5th cranial nerve (98%) odours. Spontaneous smell identification (54.7% and 59.3%) and forced choice (72.2% and 42.6%) scores were lower than those of smell detection, for both 1st and 5th cranial nerves respectively. On smell identification, volunteers scored higher in the left than in the right nostril. Females had better smell identification for both 1st and 5th cranial nerves (62.8%, 66.7%) than males (50.3%, 58.8%). Non-smokers had higher scores (65%) than smokers (59%) on smell identification for the 5th CN. CONCLUSIONS: For smell identification, females, non-smokers, and left nostril had higher scores than males, smokers, and right nostril respectively. BAST-24 is a good and reliable method to test the olfactory function in the clinical practice.

Expression of the glucocorticoid receptor alpha and beta isoforms in human nasal mucosa and polyp epithelial cells.

The lower sensitivity of the inflamed nasal mucosa to glucocorticoids might be related to an increased expression of the glucocorticoid receptor (GR) beta isoform. We investigated GRalpha and GRbeta mRNA expression in epithelial cells from nasal mucosa and nasal polyps. GRalpha mRNA was at least 1000 times more expressed than GRbeta mRNA in both tissues. GRbeta expression (mean+/-SEM of 10(3) cDNA copies/microg of total RNA) was higher in nasal polyps (1.15+/-0.19; n=27; P<0.01) than in nasal mucosa (0.62+/-0.10; n=32). Nasal polyps with > 3% of inflammatory cells had higher GRbeta levels (1.40+/-0.29; n=16) than both nasal mucosa (P<0.01) and polyps with < or = 3% of inflammatory cells (0.80+/-0.18; n=11; P<0.05). No difference in GRbeta expression was found between nasal mucosa and polyps with < or = 3% of inflammatory cells. GRbeta expression correlated with the inflammatory cell number, especially with mast cells (r=0.50, P<0.0001). There was no difference in GRalpha mRNA expression between nasal mucosa and nasal polyps. In summary, GRalpha is far more expressed than GRbeta in both tissues. The increased expression of GRbeta may be related to the presence of inflammatory cells.