Incidence Of Asthma In Adults Research Articles

Long-term exposure to ambient air pollution and road traffic noise and asthma incidence in adults: The Danish Nurse cohort

BackgroundAmbient air pollution is likely a risk factor for asthma, and recent evidence suggests the possible relevance of road traffic noise. ObjectivesWe examined the associations of long-term exposure to air pollution and road traffic noise with adult-asthma incidence. MethodsWe followed 28,731 female nurses (age > 44 years) from the Danish Nurse Cohort, recruited in 1993 and 1999, for first hospital contact for asthma from 1977 until 2015. We estimated residential annual mean concentrations of particulate matter with diameter < 2.5 µm (PM2.5) since 1990 and nitrogen dioxide (NO2) since 1970 with the Danish DEHM/UBM/AirGIS modeling system, and road traffic noise (Lden) since 1970 with the Nord2000 model. Time-varying Cox regression models were used to associate air pollution and road traffic noise exposure with asthma incidence. ResultsDuring 18.6 years’ mean follow-up, 528 out of 23,093 participants had hospital contact for asthma. The hazard ratios (HR) and 95% confidence intervals for asthma incidence associated with 3-year moving average exposures were 1.29 (1.03, 1.61) per 6.3 µg/m3 for PM2.5, 1.16 (1.07, 1.27) per 8.2 µg/m3 for NO2, and 1.12 (1.00, 1.25) per 10 dB for Lden. The HR for NO2 remained unchanged after adjustment for either PM2.5 or Lden, while the HRs for PM2.5 and Lden attenuated to unity after adjustment for NO2. ConclusionsLong-term exposure to air pollution was associated with adult-asthma incidence independently of road traffic noise, with NO2 most relevant. Road traffic noise was not independently associated with adult-asthma incidence.

Unravelling the requirement for host cell chloride channels during HRSV infection

Ion channels are a diverse class of transmembrane proteins that selectively allow ions across membranes, influencing a multitude of cellular processes. Modulation of these channels by viruses is emerging as an important host-pathogen interaction that regulates critical stages of the virus multiplication cycle including entry, replication and egress. Human respiratory syncytial virus (HRSV) causes severe respiratory tract infections globally and is one of the most lethal respiratory pathogens for infants in developing countries, with frequent development of bronchiolitis. Furthermore, it is the most significant cause of hospitalisation of infants in the UK. Evidence also indicates that severe childhood HRSV infection contributes towards the increased incidence of adult asthma. No HRSV vaccine is available, and currently the only treatment is immunoprophylaxis which is prohibitively expensive and only moderately effective; thus new treatment options are required. Utilising GFP-expressing HRSV in combination with an extensive panel of channel specific pharmacological inhibitors, we have identified an important role of cellular chloride (Cl-) channels during HRSV infection. Interestingly, pharmacological inhibition of specific Cl- channel families has ruled out involvement of the CFTR and instead highlighted a critical requirement for calcium-activated Cl- channels (CaCCs). Time of addition studies using CaCC blockers have indicated that these channels play a post-entry role during HRSV infection. Using genetic knockdown techniques we have isolated a single channel of interest and are now further investigating its role in facilitating HRSV multiplication, as well as assessing the importance of Cl- channels in replication cycles of other negative sense RNA viruses.

Investigating the requirement for host cell chloride ion channels during human respiratory syncytial virus infection

Ion channels are a diverse class of transmembrane proteins, which selectively allow ions across cellular membranes, influencing a multitude of cellular processes. Modulation of these channels by viruses is emerging as an important host-pathogen interaction, and has been demonstrated to regulate critical stages of the virus multiplication cycle including entry, replication and egress. Human respiratory syncytial virus (HRSV) causes severe respiratory tract infections (RTIs) globally and is one of the most lethal respiratory pathogens for infants in developing countries, with many cases leading to severe lower respiratory tract infections, and the development of bronchiolitis. Evidence also suggests that childhood HRSV infection contributes towards the increased incidence of adult asthma. There is no HRSV vaccine, and the only treatment is immunoprophylaxis that is prohibitively expensive and only moderately effective; thus new treatment options are required. In this study, by infecting human lung epithelial cells with HRSV in the presence of various broad-range channel modulators, Cl- channels were identified to play an important role during HRSV infection. Time of addition assays using these broad-acting Cl- channel blockers identified the stages within the HRSV lifecycle that were dependant on Cl- channel activity, and the use of family-specific Cl- channel blocking drugs identified a small sub-family of Cl-channels which, when inhibited, resulted in significantly reduced HRSV multiplication. We are now identifying the specific Cl- channel(s) facilitating the multiplication of HRSV using genetic means, and well as assessing the importance of Cl- channels in replication cycles of other negative sense RNA viruses.

Changing patterns of adult asthma incidence: results from the National Health Insurance Service\u2013National Sample Cohort (NHIS-NSC) database in Korea

This study was conducted to assess the changes in the annual incidence of adult asthma in Korea where the prevalence of asthma had increased steadily in recent decades. A population-based cohort study was conducted using the National Health Insurance Service–National Sample Cohort (NHIS-NSC), which consisted of 746,816 adults aged >20 years between 2004 and 2012. Asthma was defined by two or more physician claims on the basis of a primary diagnostic code for asthma and administration of asthma medications within 1 year. The incidence rates and annual percent change were calculated, and the influence of age and sex on the incidence rates was studied. The annual asthma incidence increased from 3.63 in 2004 to 6.07 per 1,000 person-years in 2008. Since 2008, the asthma incidence did not change significantly. The asthma incidence was higher in women than in men throughout the study periods (p < 0.001) and higher in older than younger age groups (p < 0.001). The asthma incidence did not change in all ages since 2008, except for the 20 s who showed a steady increase. The incidence of asthma in adults reached plateau in Korea, which is consistent with the results from studies in other countries.

Trends in the incidence of asthma in adults: A Korean population-based study

Background Current population-based data on the incidence of asthma in Korean adults are scarce, although the cross-sectional prevalence study had been conducted. Moreover, estimates of asthma incidence in elderly are rare. Objective We aimed to investigate the annual incidence of asthma among Korean adults and identify differences in the asthma incidence according to demographic and socioeconomic characteristics over the study period 2004–2012. Methods A population-based cohort study was conducted using the 2002–2014 National Health Insurance Service–National Sample Cohort (NHIS-NSC). It consisted of 1,025,340 randomly selected participants, comprising 2.2% of the total eligible Korean population in 2002. Among these, 746,816 adults older than 20 years receiving National Health Insurance were included in the study. The cohort consisted of 746,816 adults aged over 20 years with National Health Insurance (NHI). We defined cases as a person with two or more physician claims with a primary diagnosis of asthma (ICD 10 code J45 or J46) and asthma medications within at least 1-year interval. Age- and sex-specific incidence rates were determined by dividing the total number of adults newly diagnosed with asthma by the total number of person-years (PY) accumulated. The incidence rates were age-adjusted to according to the 2005 Korean population census. Poisson regression analysis was used to calculate sex- and age-adjusted incidence rates and to test the difference in incidence trends according to age, sex, and income groups. Trends in incidence over time were assessed using Joinpoint Regression Software. We analyzed the trend of each line segment using the annual percent change (APC), and the overall trend for the whole study period (2004–2012), using the average APC (AAPC). Results The incidence rate was significantly increasing until 2008(APC 13.8), and from 2008 to 2012, it showed decreasing trend although not significant (APC −2.9), The crude incidence rate per 1000 person-years was 4.53 in 2004, 8.04 in 2008, 7.08 in 2012, respectively. Age and sex adjustment did not change this trend. Incidence for women was higher than for men and the difference was constant according to the year. Incidence rates increased with age and this difference increased over calendar time. There were no significant differences in the incidence of asthma by five income groups. Conclusion Our population-based cohort study observed that the incidence of asthma in Korean adults (2004–2012) has not increased from 2008 onward, directly indicating the stabilization of asthma incidence as suggested in previous studies. Further studies are needed to investigate the decrease in asthma incidence rate and high incidence in susceptible groups.

Time Trend Analysis of the Prevalence and Incidence of Diagnosed Asthma and Traditional Chinese Medicine Use among Adults in Taiwan from 2000 to 2011: A Population-Based Study.

BackgroundThe aim of this study was to determine the annual trends of traditional Chinese medicine (TCM) use for prevalent and incident asthmatic adults in Taiwan from 2000 to 2011. The annual prevalence and incidence of asthma in adults among subgroups of sociodemographic factors were also investigated.MethodsA population-based study was conducted using a random sample with one million beneficiaries of all residents aged ≥18 years enrolled in the National Health Insurance program. Adults diagnosed with asthma were identified from the National Health Insurance Research Database. The annual prevalence and incidence of asthma in the adult population were estimated by using International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic codes to identify relevant cases from 2000 to 2011.ResultsThe number of annual prevalent cases of diagnosed asthma increased from 56,885 in 2000 to 101,535 in 2011. The prevalence increased significantly on annual basis, whereas the incidence rate fluctuated over time. The prevalence of TCM use by adults with asthma decreased significantly (p<0.05), from 38.58% in 2000 to 29.26% in 2011. The number of annual incident cases of diagnosed asthma decreased from 3,896 in 2000 to 2,684 in 2011. TCM use rates in asthma incident adults decreased significantly (p<0.05), from 54.24% in 2000 to 38.19% in 2011.ConclusionThe prevalence of TCM utilization is high among adults with asthma in Taiwan. However, our study demonstrated a substantial decrease in the annual prevalence of TCM use by prevalent and incident asthmatic adults in Taiwan from 2000 to 2011. In addition, the prevalence of TCM use was higher among incident cases, compared with those with prevalent cases.

Gender differences in adult-onset asthma: results from the Swiss SAPALDIA cohort study.

A higher incidence of asthma is reported in women compared with men, but evidence in later adulthood is limited. We aimed to determine the 20-year cumulative incidence of adult asthma in Switzerland and its relation to sex, taking into account age and allergic sensitisation.We assessed incidence of self-report of doctor-diagnosed asthma between 1991/1992 and 2010/2011 in 5128 subjects without asthma, aged 18-60 years at baseline. The age-related probability of asthma onset was analysed by logistic regression adjusting for potential confounders and stratified by sex and allergic sensitisation at baseline.Over 20 years, 128 (5.1%) men and 198 (7.5%) women newly reported doctor-diagnosed asthma. The adjusted odds ratio for female sex was 1.99 (95% CI 1.54-2.57) overall, 3.21 (95% CI 2.12-4.85) among nonsensitised subjects, and 1.43 (95% CI 1.02-2.02) in sensitised subjects. The probability of asthma onset decreased with increasing baseline age in women but not in men. The higher probability of new asthma in sensitised compared with nonsensitised men was unrelated to age, whereas in women it decreased with age.Asthma incidence was higher in women than in men but decreased with increasing age. The female predominance was considerably stronger in nonsensitised adults compared with those with allergic sensitisation.

Ambient air pollution and adult asthma incidence in six European cohorts (ESCAPE).

BackgroundShort-term exposure to air pollution has adverse effects among patients with asthma, but whether long-term exposure to air pollution is a cause of adult-onset asthma is unclear.ObjectiveWe aimed to investigate the association between air pollution and adult onset asthma.MethodsAsthma incidence was prospectively assessed in six European cohorts. Exposures studied were annual average concentrations at home addresses for nitrogen oxides assessed for 23,704 participants (including 1,257 incident cases) and particulate matter (PM) assessed for 17,909 participants through ESCAPE land-use regression models and traffic exposure indicators. Meta-analyses of cohort-specific logistic regression on asthma incidence were performed. Models were adjusted for age, sex, overweight, education, and smoking and included city/area within each cohort as a random effect.ResultsIn this longitudinal analysis, asthma incidence was positively, but not significantly, associated with all exposure metrics, except for PMcoarse. Positive associations of borderline significance were observed for nitrogen dioxide [adjusted odds ratio (OR) = 1.10; 95% CI: 0.99, 1.21 per 10 μg/m3; p = 0.10] and nitrogen oxides (adjusted OR = 1.04; 95% CI: 0.99, 1.08 per 20 μg/m3; p = 0.08). Nonsignificant positive associations were estimated for PM10 (adjusted OR = 1.04; 95% CI: 0.88, 1.23 per 10 μg/m3), PM2.5 (adjusted OR = 1.04; 95% CI: 0.88, 1.23 per 5 μg/m3), PM2.5absorbance (adjusted OR = 1.06; 95% CI: 0.95, 1.19 per 10–5/m), traffic load (adjusted OR = 1.10; 95% CI: 0.93, 1.30 per 4 million vehicles × meters/day on major roads in a 100-m buffer), and traffic intensity (adjusted OR = 1.10; 95% CI: 0.93, 1.30 per 5,000 vehicles/day on the nearest road). A nonsignificant negative association was estimated for PMcoarse (adjusted OR = 0.98; 95% CI: 0.87, 1.14 per 5 μg/m3).ConclusionsResults suggest a deleterious effect of ambient air pollution on asthma incidence in adults. Further research with improved personal-level exposure assessment (vs. residential exposure assessment only) and phenotypic characterization is needed.CitationJacquemin B, Siroux V, Sanchez M, Carsin AE, Schikowski T, Adam M, Bellisario V, Buschka A, Bono R, Brunekreef B, Cai Y, Cirach M, Clavel-Chapelon F, Declercq C, de Marco R, de Nazelle A, Ducret-Stich RE, Ferretti VV, Gerbase MW, Hardy R, Heinrich J, Janson C, Jarvis D, Al Kanaani Z, Keidel D, Kuh D, Le Moual N, Nieuwenhuijsen MJ, Marcon A, Modig L, Pin I, Rochat T, Schindler C, Sugiri D, Stempfelet M, Temam S, Tsai MY, Varraso R, Vienneau D, Vierkötter A, Hansell AL, Krämer U, Probst-Hensch NM, Sunyer J, Künzli N, Kauffmann F. 2015. Ambient air pollution and adult asthma incidence in six European cohorts (ESCAPE). Environ Health Perspect 123:613–621; http://dx.doi.org/10.1289/ehp.1408206

Younger pubertal age is associated with allergy and other atopic conditions in girls.

Early menarche is linked to higher incidence of adult asthma, suggesting that earlier puberty may influence type 2 immune response characteristics of allergic diseases. We examined the hypothesis that timing of breast and pubic hair development, which precede menarche, is associated with increased childhood atopic conditions. Girls were enrolled at 6-8 yr of age (2004-2007) in the Breast Cancer and the Environment Research Program Puberty Study and were followed through 2011. Pubertal stages were assessed and atopic conditions were queried annually. Associations of age at pubertal stage 2 for breast or pubic hair development with atopic conditions were assessed using prevalence ratios (PR) or odds ratios (OR) and 95% confidence intervals (CI) from log-binomial regression and generalized estimating equation models, controlling for body mass index and other covariates. A total of 1055 girls with medical and pubertal stage data were included. Asthma (ever vs. never) was associated with younger pubarche (≤10 vs. >10 yr, PR = 1.15, CI: 1.04-1.28 adjusted for race/ethnicity and site; PR = 1.13, CI: 1.01-1.25 further adjusted for BMI), but not thelarche. In longitudinal models, risk of developing allergies increased with younger age at pubarche (adjusted OR = 1.60, CI: 1.10-2.34; ≤10 vs. >10 yr). Risks were highest among black girls with earlier pubarche (n = 248/326); for allergies, their fully adjusted OR was 2.35, CI: 1.06-5.19 for pubarche ≤10 vs. >10 yr. Atopic conditions during childhood are associated with younger age at pubarche, independent of obesity, and these relationships may vary by racial/ethnic groups.

Erratum: Increased Risk of Asthma in Patients with Systemic Lupus Erythematosus

of asthma could be caused by lupus pulmonary involvement; however, there is insufficient evidence that asthma is a result of lupus interstitial pneumonitis or pleuritis. To the best of our knowledge, a restrictive functional defect was observed in lupus pneumonitis, interstitial pulmonary fibrosis, and pleural effusion, which differed from an obstructive functional defect in asthma (7). Therefore, SLE plays an extremely important role in the development of asthma. With increasing age, other risk factors also contribute to the incidence of asthma, and the relative risk of asthma consequently decreases. Adult-onset asthma is believed to be an underestimated issue, affecting approximately 4–8% of patients older than 65 years (8). A review article by Eagan and coworkers reported that the pooled estimated incidence of adult asthma from general population cohort studies was 59 and 44 per 10,000 person-years in women and men, respectively (9). These findings were close to the incidence found in our non-SLE elderly groups. We believe a small proportion of cases are misclassified as asthma; however, these contributions should be equivalent in the two cohorts. In conclusion, the incidence of asthma may increase in patients with SLE with increasing age, and the data clearly demonstrate that IRR decreases inversely with increasing age. n

Traffic related air pollution and adult asthma incidence: the European Study of Cohorts for Air Pollution Effects (ESCAPE)

Background: The role of air pollution in the development of adult onset asthma remains uncertain. The objective was to assess the impact of long-term exposure to traffic related air pollution on ad...

Metabolic syndrome and incidence of asthma in adults: the HUNT study

Obesity is a risk factor for incident asthma in adults, and obesity is a major component of metabolic syndrome. This study aimed to explore the associations of metabolic syndrome and its components with the cumulative incidence of asthma in adults. We conducted a prospective cohort study of participants who were asthma-free at baseline (n = 23 191) in the Nord-Trøndelag Health Study from 1995 to 2008. Baseline metabolic syndrome was categorised using the definition of the Joint Interim Statement from several international organisations. Incident asthma was self-reported at follow-up, which averaged 11 years. Metabolic syndrome was a risk factor for incident asthma (adjusted OR 1.57, 95% CI 1.31-1.87). This association was consistent in sensitivity analyses using a stricter asthma definition (adjusted OR 1.42, 95% CI 1.13-1.79). Among the components of metabolic syndrome, two remained associated with incident asthma after mutual adjustment for the other metabolic components: high waist circumference (adjusted OR 1.62, 95% CI 1.36-1.94) and elevated glucose or diabetes (adjusted OR 1.43, 95% CI 1.01-2.04). Metabolic syndrome and two of its components (high waist circumference and elevated glucose or diabetes) were associated with an increased risk of incident asthma in adults.

Occupational Asthma Incidence: Findings from the Behavioral Risk Factor Surveillance System Asthma Call-Back Survey—United States, 2006–2009

Background. Occupational asthma (OA) is new-onset asthma or the recurrence of previously quiescent asthma caused by workplace exposures. Objective. To estimate the incidence of population-based new-onset OA and the proportion of incident asthma that is work-related. Methods. Behavioral Risk Factor Surveillance System and Asthma Call-back Survey data collected from persons aged ≥18 years during 2006–2009 in 38 states and the District of Columbia were analyzed. Incident health professional-diagnosed new-onset OA cases were persons whose asthma was diagnosed for the first time within the past 12 months whose health professional indicated their asthma was related to their work. Incident potential new-onset OA cases were persons with asthma diagnosed within the past 12 months who did not have health professional-diagnosed work-related asthma but described their asthma as caused by workplace exposures. The proportion of incident asthma that is work-related was calculated using the 2006–2008 estimate of adult asthma incidence (3800 per million). Results. The estimated annual incidence of health professional-diagnosed new-onset OA was 179 (95% CI: 113–245) per million population. For combined health professional-diagnosed and potential new-onset OA the incidence was 692 (95% CI: 532–853) per million population. The proportion of incident asthma among adults that is work-related was 4.7% for health professional-diagnosed new-onset OA and 18.2% for combined health professional-diagnosed and potential new-onset OA. Conclusions. New-onset asthma in as many as one of six adult patients might be associated with work. Clinicians should consider the role of occupational exposures when evaluating adults with incident asthma which may uncover opportunities for early intervention and reversal of an otherwise chronic disease.

Mould and dampness in dwelling places, and onset of asthma: the population-based cohort ECRHS

ObjectivesTo study new onset of adult asthma in relation to dampness and moulds in dwelling places.MethodsTotally, 7104 young adults from 13 countries who participated in the European Community Respiratory Health...

Assessment of prevalence of allergic rhinitis and bronchial asthma in Samara region

Background. The purpose of this study was to investigate the prevalence and incidence of allergic rhinitis (AR) and bronchial asthma (BA) among different groups of population of Samara region during 2001—2010. Methods. Material for analysis was taken from the statistic forms of municipality hospitals of Samara and the Samara region (form No. 12) during 2001—2010 in comparison with the corresponding indicators of Volga federal region (PFO) and the Russian Federation. Results. Prevalence of BAin all groups of patients in the Samara region in 2009 was revealed. These indicators were more than such indicators in Russian Federation — among children on 25%, in teenagers on 38%, in adult on 50%. Prevalence of AR among children and teenagers exceeded indicators in Russian Federation — among children on 44%, teenagers — on 68%. The incidence of asthma in adults is 2,5 times higher than the incidence of AR (95,8—30,5 per 100 thousand). Conclusion. High prevalence of AR and asthma in the Samara region with a tendency to increase, the discrepancy indices studied data from epidemiological studies that require further implementation of international recommendations for diagnosis, treatment and prevention of AR among general practitioners.

Smoking and asthma: Disentangling their mutual influences using a longitudinal approach

The association between smoking and asthma remains unclear and has mostly been assessed in cross-sectional studies, with potential selection bias ("healthy smoker effect"). Using a longitudinal approach, the aims were to assess whether 1) childhood asthma modifies smoking initiation, 2) active smoking influences asthma incidence in adults and 3) active smoking among subjects with asthma influences the persistence of the disease or the 12-year evolution in lung function in children and adults. Subjects (513 children and 1190 adults) were recruited and followed-up for 12 years in the context of the EGEA study (Epidemiological study on the Genetics and Environment of Asthma). Childhood asthma was not associated with a decreased probability of starting active smoking (Hazard Ratio, HR = 0.96; 95% confidence interval (CI): 0.72, 1.27). Smoking at baseline was associated with a higher risk for asthma incidence in adulthood (HR = 1.95, 95% CI: 1.00, 3.77). Among subjects with asthma, smoking was unrelated to lung function evolution; however, among children with moderate to severe asthma at inclusion, smoking tended to slow down the lung function growth (P = 0.04). These findings support the hypothesis that childhood asthma does not prevent smoking initiation and confirm that active smoking has a deleterious role on asthma. Altogether this study emphasizes the importance of active smoking as a serious public health problem particularly for children and women.

Occupational exposure and incidence of respiratory disorders in a general population

To study the effect of occupational exposure on the incidence of adult asthma and six respiratory symptoms using a job exposure matrix (JEM). From 1985, we conducted an 11-year community cohort study on the incidence of asthma and respiratory symptoms in Western Norway (N=2401, aged 15-70 years at baseline). The analyses in the current study were based on subjects < or =65 years at baseline, since those >65 years were unlikely to experience significant occupational exposures within the follow-up period. More women than men were exposed to biological dust (38% versus 29%), while more men were exposed to mineral dust (48% versus 19%), and gas or fumes (58% versus 53%). After adjusting for age, educational level, smoking, and previous occupational exposures, we found that high exposure to biological dust exposure was significantly related to a higher incidence of chronic and morning cough in men; for women, low exposure was related to attacks of dyspnea. Low exposure to workplace gas or fumes was significantly related to incident phlegm cough and attacks of dyspnea for women, while for men, high exposure was related to dyspnea grade 2. For the incidence of asthma and phlegm cough, after adjusting for all confounders, we found a significant interaction between workplace exposures and gender, where women had a higher risk of disease. Assessed by a JEM, occupational airborne exposure was weakly related to the incidence of asthma and respiratory symptoms, significantly more so for women than for men.

Sarcoidosis, asthma, and asthma-like symptoms among occupants of a historically water-damaged office building

Sarcoidosis is a granulomatous disease of unknown etiology with evidence of association with exposure to microbial agents. In June 2006, we investigated a sarcoidosis cluster among office workers in a water-damaged building. In the course of the investigation, we became aware of a high rate of respiratory complaints including asthma and asthma-like symptoms. We conducted case finding for physician-diagnosed sarcoidosis and asthma and administered a health questionnaire survey and pulmonary function tests (PFTs) to consenting occupants. We compared prevalence ratios (PRs) to the Environmental Protection Agency's Building Assessment Survey and Evaluation study (BASE) and the National Health and Nutrition Examination Survey (NHANES). We identified six sarcoidosis cases. The current building prevalence is 2206 cases/100,000 population, elevated, compared with the US population range of <1-40 cases/100,000. Of current occupants, 77% (105) participated in the health questionnaire survey and 64% (87) in PFTs. Physician-diagnosed asthma was elevated, compared with the US adult population. Adult asthma incidence was 3.3/1000 person-years during the period before building occupancy and 11.5/1000 person-years during the period after building occupancy. Comparisons with US office workers (BASE) yielded elevated PRs for shortness of breath [PR, 9.6; 95% confidence interval (CI), 6.1-15.2], wheeze (PR, 9.1; 95% CI 5.6-14.6), and chest tightness (PR, 5.1; 95% CI 2.8-9.0). PFT results supported reports of respiratory symptoms and diagnoses. Based on our findings building occupants were relocated. The remission of occupational asthma caused by certain known antigens improves with early diagnosis and removal from exposure. As a suspected antigen-mediated disease, sarcoidosis might also benefit if affected persons are isolated from continued exposure. Our investigation identified a high prevalence of new-onset sarcoidosis, and asthma among workers of a water damaged building with a history of indoor environmental quality complaints. Removal of all individuals from such environments until completion of building diagnostics, environmental sampling and complete remediation is a prudent measure when feasible.

Exposure to substances in the workplace and new-onset asthma: an international prospective population-based study (ECRHS-II)

The role of exposure to substances in the workplace in new-onset asthma is not well characterised in population-based studies. We therefore aimed to estimate the relative and attributable risks of new-onset asthma in relation to occupations, work-related exposures, and inhalation accidents. We studied prospectively 6837 participants from 13 countries who previously took part in the European Community Respiratory Health Survey (1990-95) and did not report respiratory symptoms or a history of asthma at the time of the first study. Asthma was assessed by methacholine challenge test and by questionnaire data on asthma symptoms. Exposures were defined by high-risk occupations, an asthma-specific job exposure matrix with additional expert judgment, and through self-report of acute inhalation events. Relative risks for new onset asthma were calculated with log-binomial models adjusted for age, sex, smoking, and study centre. A significant excess asthma risk was seen after exposure to substances known to cause occupational asthma (Relative risk=1.6, 95% CI 1.1-2.3, p=0.017). Risks were highest for asthma defined by bronchial hyper-reactivity in addition to symptoms (2.4, 1.3-4.6, p=0.008). Of common occupations, a significant excess risk of asthma was seen for nursing (2.2, 1.3-4.0, p=0.007). Asthma risk was also increased in participants who reported an acute symptomatic inhalation event such as fire, mixing cleaning products, or chemical spills (RR=3.3, 95% CI 1.0-11.1, p=0.051). The population-attributable risk for adult asthma due to occupational exposures ranged from 10% to 25%, equivalent to an incidence of new-onset occupational asthma of 250-300 cases per million people per year. Occupational exposures account for a substantial proportion of adult asthma incidence. The increased risk of asthma after inhalation accidents suggests that workers who have such accidents should be monitored closely.

Vehicle exhaust exposure in an incident case-control study of adult asthma

The objective of this case-control study was to evaluate whether traffic-related air pollution exposure at home increases the risk of asthma in adults and to compare two commonly used exposure variables and differences between urban and rural living. Incident cases of asthma and matched controls of subjects aged 20-60 yrs were recruited in Luleå, Sweden. In total 203 cases and 203 controls were enrolled in the study. Exposure was estimated by traffic flow and measured levels of outdoor nitrogen dioxide (NO2) in the surrounding environment of each home, respectively. The relationship between measured levels of NO2 and traffic flow was studied using linear regression. The results indicated a nonsignificant tendency between living in a home close to a high traffic flow and an increased risk of asthma. The association between asthma and measured NO2 was weak and not significant, but the skin-prick test result acted as an effect modifier with a borderline significant association among positives. The correlation between traffic flow and outdoor NO2 was low. The results suggest that living close to high traffic flows might increase the asthma incidence in adults, while the tendency for nitrogen dioxide was only seen among atopics. Traffic flow and nitrogen dioxide had a lower than expected correlation.