***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The aetiology of nasal polyps remains obscure . Although clinical ly associated with asthma , notably in women , there is a marked male preponderance of polyposis . This study aim ed to explore environmental pollutant triggers and gender differences in risk factors for nasal polyps . In total , 900 patients having surgery for polyposis and 120 new patients with nasal polyps completed a question naire with regard to occupational dust and chemical exposure . The male to female ratio was 2:1 , and 52 % were smokers , although only 37 % of women smoked compared with 66 % of men . Exposure to occupational dusts and chemicals was noted in 45 % ( retrospective ) and 53 % ( prospect i ve ) of respondents . Women were 1.6 times more likely to be asthmatic and 2.7 times more likely to have allergic rhinitis than men . Men were 2.25 times more likely to be smokers and 2.48 times more likely to have been exposed to chemicals and dusts than women ( all statistically significant differences ) . No significant gender associations were found for hayfever , eczema , aspirin intolerance , alcohol intake or hobby dust exposure Background The cause of nonallergic rhinitis ( NAR ) and its relation to lower airway disease remains unclear . The purpose of this study was to perform a descriptive analysis of the occurrence of rhinitis in a Danish general population with focus on NAR and its association with smoking and lower airway disease . Methods A population -based , cross-sectional study conducted in Copenhagen , Denmark was performed . A r and om sample from the general population ( n = 7931 ; age , 18–69 years ) was invited to a general health examination including measurements of serum-specific immunoglobulin E ( IgE ) to common aeroallergens ;  3471 ( 44 % ) persons were accepted . For further analysis , we divided the population into the following groups : ( I ) negative specific IgE and no rhinitis ( controls ) ; ( II ) negative specific IgE and rhinitis ( NAR ) ; ( III ) positive specific IgE and rhinitis ( allergic rhinitis [ AR ] ) ; and ( IV ) positive specific IgE but no rhinitis ( sensitized ) . Results We found that NAR was associated with asthma ( odds ratio [ OR ] = 2.51 [ 1.87–3.37 ] ) ; chronic bronchitis ( OR = 2.27 [ 1.85–2.79 ] ) ; current smoking ( > 15 g/day ; OR = 1.57 [ 1.18–2.08 ] ) ; lower forced expiratory volume in 1 second/forced vital capacity ( FEV1/FVC ) ratios and reduced FEV1 values . The association with chronic bronchitis was stronger in NAR than in AR , whereas the opposite was true for asthma . FEV1/FVC of < 70 % was not significantly associated to any group . Conclusion This epidemiological study indicates that both asthma and chronic bronchitis are important comorbidities in NAR confirming the “ united airway ” hypothesis , and that smoking might be a significant modulator of disease . Although NAR was significantly associated with poor lung function , no significant association with chronic obstructive pulmonary disease was shown OBJECTIVES To compare total nasal resistance ( TNR ) in upright and supine positions in patients who did and did not complain of nocturnal ( supine ) nasal congestion symptoms without daytime ( upright ) congestion , and to determine what other conditions were associated with nocturnal nasal congestion ( NNC ) symptoms . STUDY DESIGN A prospect i ve study comparing objective ly measured nasal airflow in different positions ( upright and reclining ) with subjective patient symptoms . METHODS Subjects completed a question naire about nasal symptoms . Anterior rhinomanometry was performed with patients upright , reclined 45 degrees , and supine .  TNR in subject subsets was compared using the Student t test . RESULTS TNR did not differ between upright patients with ( n = 27 ) and without ( n = 20 ) NNC . Supine TNR ( P < .04 ) and increase in TNR ( P < .02 ) between upright and supine was greater in patients with NNC . Smokers ( n = 15 , 10 with NNC , 5 without ) had greater TNR increases when supine versus nonsmokers ( P < .02 ) . Patients with rhinitis symptoms ( n = 29 , 18 with NNC , 11 without ) had greater TNR increases when supine than patients without rhinitis ( P < .01 ) . Patients who both smoked and had rhinitis ( n = 11 , 7 with NNC , 4 without ) had a greater supine TNR than patients who smoked or had rhinitis alone ( P < .02 ) . CONCLUSIONS Some patients without daytime nasal congestion experience NNC . They have a significantly greater TNR increase when supine versus patients without NNC . Smokers and patients with rhinitis , with or without NNC , have a significantly greater TNR increase when supine versus nonsmokers or patients without rhinitis . Smoking cessation and treatment of rhinitis may improve the patients ' NNC Objective --To estimate the prevalence of isolated self-reported allergic and non-allergic rhinitis symptoms in an adult population and to explore the relations to age , gender , olfaction and smoking habits . Material and methods --Self-judged health and environmental exposures were investigated by means of a question naire survey administered to a stratified r and om sample of 15,000 adults in Stockholm County . Results --A total of 10,670 individuals were included in the analysis , corresponding to a response rate of 73 % . The results revealed a high prevalence of self-reported non-allergic rhinitis , 19 % , almost as high as the prevalence of self-reported allergic rhinoconjunctivitis , 24 % . In contrast to current clinical opinion , we did not find a significant increase in the prevalence of non-allergic symptoms with increased age . There were no statistically significant gender differences in the prevalence of either allergic or non-allergic symptoms . A reduced sense of smell was twice as common in the non-allergic group , 23 % , as in the healthy population . The prevalence of rhinitis symptoms differed according to smoking habits . Conclusion --Both self-reported allergic rhinitis symptoms and non-allergic nasal symptoms are frequent in the population sample .  Self-reported non-allergic nasal symptoms seem to occur independent of age and reduced olfactory sense is a common complaint among these subjects . The prevalence of self-reported allergic and non-allergic nasal symptoms did not differ much between men and women or between individuals with different smoking habits STUDY OBJECTIVE The upper and lower airways are continuous . While upper airway symptoms are common in COPD patients , with accumulating evidence to suggest increased nasal inflammation , the relationships among upper airway , lower airway , and systemic inflammatory indexes have not been studied . We aim ed to confirm that there is heightened nasal inflammation in COPD patients , to test the hypothesis that the degree of upper airway inflammation relates to the degree of lower airway inflammation , and to investigate the underlying associations with bacterial carriage and the systemic inflammatory response . DESIGN Prospect i ve cohort study . SETTING Outpatient Department , London Chest Hospital , London , UK . PARTICIPANTS Forty-seven patients with COPD and 12 control subjects of similar age , sex , and smoking status . MEASUREMENTS  Serum , nasal wash fluid , and sputum sample s  were obtained from 47 stable patients with COPD for the analysis of inflammatory indexes and bacterial colonization . Nasal wash fluid specimens were obtained from 12 control subjects . RESULTS COPD patients had an increased nasal interleukin (IL)-8 concentration compared to control subjects ( difference , 97.2 pg/mL ; p = 0.009 ) . The nasal IL-8 concentration in COPD patients correlated with that in sputum ( r = 0.30 ; p = 0.039 ) . In both the upper and lower airways of patients with COPD , the IL-8 concentration was associated with indexes of bacterial colonization . Patients colonized with a sputum potentially pathogenic microorganism had a higher total nasal bacterial load ( difference , 1.5 log cfu/mL ; p = 0.016 ) . We did not find significant relationships between the degree of upper or lower airway inflammation , or bacterial carriage , and the systemic inflammatory response . CONCLUSIONS COPD is associated with an increased nasal concentration of the neutrophil chemoattractant protein IL-8 , the degree of which reflects that present in the lower airway . A relationship between lower airway bacterial colonization , postnasal drip , and higher nasal bacterial load may suggest a mechanism underlying this finding . This study is the first to report a correlation between the degree of upper and lower airway inflammation in COPD Conclusion . There is high prevalence of lower airway diseases in patients with chronic rhinosinusitis and frequently co-existing lower airway diseases have not been diagnosed before . Objectives . To examine the prevalence of lower airway diseases in patients with chronic rhinosinusitis . Methods . Seventy-three consecutive patients with chronic rhinosinusitis were enrolled in this prospect i ve study . With routine physical examination , spirometry and methacholine bronchial provocation test were performed and chest simple radiograph or chest computed tomography was taken . Results . Thirty patients ( 41.1 % ) had lower airway diseases . There were 8 patients with asthma , 5 with asymptomatic bronchial hyperresponsiveness , 11 with small airway disease , 2 with chronic obstructive pulmonary disease and 4 with bronchiectasis . Of these 30 patients , 21 patients ( 70.0 % ) were first diagnosed as having lower airway diseases in this study The effect of tobacco smoking on chronic rhinosinusitis ( CRS ) is not yet well‐delineated . The purpose of this investigation was to evaluate the overall effect of smoking on postoperative outcomes ( endoscopic score and health‐related quality ‐of‐life [ HRQoL ] ) after endoscopic sinus surgery ( ESS ) for CRS and to determine if volume of daily smoking impacts outcomes Background When associated with lower airway involvement , the morbidity and the cost of chronic rhinosinusitis ( CRS ) can increase . The aim of this prospect i ve study was to assess the clinical and radiological characteristics of the upper airways in CRS patients scheduled for functional endoscopic sinus surgery and to correlate these findings with the functional changes of the lower airways . Methods Twenty-five adult patients with CRS were subjected to clinical and endoscopic assessment s , computed tomography scan , and allergic assessment s using vali date d scoring systems . Lower airways were assessed by clinical history , pulmonary function test , histamine bronchial provocation test , and chest x rays . Results Sixty percent of CRS patients were shown to have associated lower airway involvement , i.e. , 24 % had asthma and 36 % had small airway disease ( SAD ) . Nasal congestion and nasal polyps were the most common clinical findings in both of these subgroups of patients . In addition , there was a negative correlation between computed tomography scan findings of the sinuses and the obstructive parameters on pulmonary function test in SAD but not in the asthma subgroup . Conclusion These results showed that different kinds of lower airway involvement frequently could be associated with CRS . Some are manifest such as asthma and some are hidden such as SAD and histamine bronchial hyperresponsiveness The relation between chronic rhinosinusitis ( CRS ) and the associated lower airways involvement is not clear yet . In this context , the aim of this prospect i ve study was to evaluate the correlation between  middle meatal lavage ( MML ) and bronchoalveolar lavage ( BAL ) cytology  in adult CRS patients . Based on clinical history and pulmonary function changes , CRS patients were divided into three subgroups : asthma , small airway disease ( SAD ) and normal lower airway ( NLA ) subgroups . Preoperatively , 50 MMLs and 25 BALs were performed in 25 CRS patients scheduled for FESS .  At 1000X power microscopic magnifications , 48 MML and 24 BAL cytospin slides were examined for total and differential cell counts ( DCC ) . This study showed that eosinophils were the dominant inflammatory cells in MMLs of the asthma subgroup and were significantly correlated to FEVI ( p = 0.042 ) and Tiffineau index ( p = 0.037 ) . On the other h and , neutrophils were the dominant inflammatory cells in MMLs of the SAD subgroup and significantly correlated to FEF75 % and Tiffinau index ( p = 0.013 and p = 0.012 respectively ) . There was no significant correlation between MML and BAL cell differential counts in CRS patients ( p > 0.05 ) . The data showed that the lower airways involvement in CRS patients could be related to the dominant type of inflammatory cells in the upper airways OBJECTIVES /HYPOTHESIS The purpose of this study is to report on long-term outcomes in a prospect i ve study comparing the quality -of-life outcomes in smokers and nonsmokers undergoing functional endoscopic sinus surgery .  STUDY DESIGN : Prospect i ve clinical trial . METHODS A total of 235 patients were prospect ively enrolled at a single tertiary academic center .  Preoperative Sino-Nasal Outcomes Test (SNOT)-20 scores and comprehensive demographic and smoking data were obtained . Preoperative SNOT-20 scores  were compared to postoperative SNOT-20 scores . RESULTS Long-term follow-up results were available 
    Output:
    
Furthermore , we present evidence that smoking on its own can cause nasal disease and that , in COPD patients , nasal inflammation mimics that of the bronchi .
All this evidence suggests that COPD -related sinonasal disease does exist and that smoking on its own rather than systemic inflammation triggers the condition .