Outcome of occupational asthma due to cobalt hypersensitivity. [The response to a specific bronchial provocation test and the evolution of occupational asthma. A longitudinal study in subjects with toluene diisocyanate-induced asthma]. Reduction in asthma morbidity in children as a result of home remediation aimed at moisture sources. Evaluation of Community Action Against Asthma: a community health worker intervention to improve children's asthma-related health by reducing household environmental triggers for asthma. Longitudinal decline in lung function in patients with occupational asthma due to western red cedar. [Course of isocyanate-induced asthma in relation to exposure cessation: longitudinal study of 50 subjects]. [Follow-up of latex-induced occupational asthma]. Encasement of bedding does not improve asthma in atopic adult asthmatics. Reduction of environmental tobacco smoke exposure in asthmatic children. A 2-year follow-up. The PREVASC study: the clinical effect of a multifaceted educational intervention to prevent childhood asthma. Bronchial responsiveness decreases in relocated aluminum potroom workers compared with workers who continue their potroom exposure. Clinical and socio-professional fate of isocyanate-induced asthma. Clinical features and natural history of occupational asthma due to western red cedar (Thuja plicata). Asthma management and environmental tobacco smoke exposure reduction in Latino children: a controlled trial. Educational intervention decreases exhaled nitric oxide in farmers with occupational asthma. The respiratory effects of reduction of mite allergen in the bedrooms of asthmatic children--a double-blind controlled trial. Improved health after intervention in a school with moisture problems. A randomized trial to reduce passive smoke exposure in low-income households with young children.
We performed a follow-up study on nine subjects with occupational asthma due to cobalt hypersensitivity confirmed by a specific bronchial provocation test. Both at diagnosis and at the two follow-up visits (1 and 3 years after the diagnosis, respectively), we graded the severity of asthmatic symptoms and the need for antiasthma treatment and performed lung function tests, measurement of airways responsiveness to methacholine (PD15) and skin tests. The evolution of the disease was established on the basis of the increase or decrease in asthmatic symptoms and the requirements for medication, FEV1 and PD15. After cessation of exposure, two subjects recovered, five improved and one remained stable; the subject who carried on working in the same environment deteriorated. The improvement in symptoms, medication need and lung function occurred earlier and in a larger number of patients than the improvement in methacholine hyperreactivity. At follow-up, the inhalation test with cobalt was repeated on three subjects who had stopped exposure and were asymptomatic and again they had bronchoconstriction. Our data show that early diagnosis and early removal from exposure after the onset of asthma are important factors for a favourable evolution of the disease and that specific and non-specific bronchial hyperresponsiveness can persist even in asymptomatic subjects no longer exposed to the sensitizing agent. The aim of this study was to investigate the progression and long-term consequences of occupational asthma and to evaluate the effect of the pattern of response to specific bronchoprovocation test (SBPT) in the prognosis of occupational asthma among 40 subjects with asthma due to toluene diisocyanate (TDI). Nine subjects had immediate asthma, 25 subjects had late asthma and 6 subjects had dual asthma. Respiratory symptoms, persistence of exposure to TDI and lung function have been investigated both at diagnosis and at follow-up examination. At follow-up examination, 70.0% of the subjects were not exposed to TDI, and only 14.3% of "non-exposed" subjects were completely asymptomatic. At follow-up examination, 71.4% of "exposed" subjects and 55.6% of "non-exposed" subjects were regularly treated with medications because of their asthma (no statistical difference). No significant differences have been found in symptoms prevalence or lung function between "exposed" and "non-exposed" subjects. After comparing the results obtained at diagnosis and at follow-up examination, a significant decrease in FVC both in "exposed" and "non-exposed" groups (p < 0.005 and p < 0.0005, respectively) and a significant decrement in FEV1 (p < 0.05) and FVC (p < 0.0005) among the subjects with late asthma, was found. We can conclude that, despite the removal from TDI exposure, occupational asthma can lead to permanent disability with important socio-economic consequences, and late response to SBPT may be a negative prognostic factor in TDI asthma. Home dampness and the presence of mold and allergens have been associated with asthma morbidity. We examined changes in asthma morbidity in children as a result of home remediation aimed at moisture sources.
                In this prospective, randomized controlled trial, symptomatic, asthmatic children (n = 62), 2-17 years of age, living in a home with indoor mold, received an asthma intervention including an action plan, education, and individualized problem solving. The remediation group also received household repairs, including reduction of water infiltration, removal of water-damaged building materials, and heating/ventilation/air-conditioning alterations. The control group received only home cleaning information. We measured children's total and allergen-specific serum immuno-globulin E, peripheral blood eosinophil counts, and urinary cotinine. Environmental dust samples were analyzed for dust mite, cockroach, rodent urinary protein, endotoxin, and fungi. The follow-up period was 1 year.
                Children in both groups showed improvement in asthma symptomatic days during the preremediation portion of the study. The remediation group had a significant decrease in symptom days (p = 0.003, as randomized; p = 0.004, intent to treat) after remodeling, whereas these parameters in the control group did not significantly change. In the postremediation period, the remediation group had a lower rate of exacerbations compared with control asthmatics (as treated: 1 of 29 vs. 11 of 33, respectively, p = 0. 003; intent to treat: 28.1% and 10.0%, respectively, p = 0.11).
                Construction remediation aimed at the root cause of moisture sources and combined with a medical/behavioral intervention significantly reduces symptom days and health care use for asthmatic children who live in homes with a documented mold problem. This article describes the evaluation of a community-based participatory research (CBPR) community health worker (CHW) intervention to improve children's asthma-related health by reducing household environmental triggers for asthma. After randomization to an intervention or control group, 298 households in Detroit, Michigan, with a child, aged 7 to 11, with persistent asthma symptoms participated. The intervention was effective in increasing some of the measures of lung function (daily nadir Forced Expiratory Volume at one second [p = .03] and daily nadir Peak Flow [p = .02]), reducing the frequency of two symptoms ("cough that won't go away," "coughing with exercise"), reducing the proportion of children requiring unscheduled medical visits and reporting inadequate use of asthma controller medication, reducing caregiver report of depressive symptoms, reducing concentrations of dog allergen in the dust, and increasing some behaviors related to reducing indoor environmental triggers. The results suggest a CHW environmental intervention can improve children's asthma-related health, although the pathway for improvement is complex. There are few reports about longitudinal changes in lung function in asthmatic patients. Patients with asthma had a greater loss of lung function than normal healthy adults. To date, there have been no studies about the longitudinal changes in lung function in patients with occupational asthma.
                280 male patients with red cedar asthma (RCA) who were followed up for at least one year were the study group. The exposed controls consisted of 399 male sawmill workers. Forced expiratory volume in one second (FEV1) was measured with a Collins water spirometer. Changes in FEV1 over time (FEV1 slope) were calculated by a two point method for each subject. Atopy was considered to be present if the subjects showed at least one positive response to three allergens by skin prick test.
                Multiple regression analysis was carried out to examine factors that might affect longitudinal decline in FEV1. Patients with RCA who were still exposed had a greater decline in FEV1 slope (-26 ml/y) than sawmill workers. Smokers also showed a greater rate of decline in FEV1 (-43 ml/y) than non-smokers.
                Patients with RCA who continued to be exposed had a greater rate of decline in FEV1 than sawmill workers. Early diagnosis of occupational asthma and removal of these patients from a specific sensitiser is important in the prevention of further deterioration of lung function and respiratory symptoms. Isocyanates, particularly Toluene Diisocyanate (TDI), have been the most common cause of occupational asthma for decades. Fifty workers with a diagnosis of isocyanate-induced asthma were followed up for a mean period of 8.4 years. Pulmonary function testing for FVC and FEV1, allergological tests, nonspecific bronchial challenge to methacholine and specific bronchial challenge to isocyanates were performed at the time of diagnosis and during follow-up. Data on symptoms and drug response were rated on a scale. Patients were subdivided into two groups based on persistence of (A; 13 patients) or removal from (B; 37 patients) isocyanate exposure. There were no significant differences in any characteristic between the two groups at the time of diagnosis. At follow-up, group B subjects showed significant improvement in symptoms, consequent reduction in use of medications and increase in PD20. None worsened, sixteen (43.3%) remained stable, twelve (32.4%) improved and nine (24.3%) became asymptomatic. The latter subjects were generally younger, they had shorter duration of symptoms and exposure to the agents, and longer removal from exposure, although none of these differences was significant. In 67% of cases they had an immediate reaction to TDI challenge. By contrast, the condition of group A patients deteriorated significantly during the follow-up period in terms of symptoms, pulmonary function parameters, PD20 and use of medications. Overall, seven subjects (53.8%) worsened during follow-up and none improved. Group B subjects were further divided into subgroups B1 and B2 based on duration of removal from exposure: B1 < 10 years, B2 > or = 10 years. There were no significant differences between the two subgroups, even though PD20 was higher in B2. The present study confirms that early diagnosis and immediate removal from exposure are crucial, though not always sufficient, for a favourable evolution of the disease. We studied 29 subjects with latex-induced occupational asthma in a follow-up of 5 +/- 3 years. Initial and follow-up visits included a questionnaire and measurement of lung volumes, bronchial responsiveness to methacholine (PD20FEV1), and latex-specific serum IgE levels. At follow-up, 17 subjects were no longer exposed to latex, whereas 12 subjects had reduced exposure. Asthma and rhinitis symptoms, use of steroids and bronchial hyperresponsiveness improved significantly at follow-up, whereas mean FEV1% and FVC% decreased (p < 0.05). Multiple regression analysis showed that the main determinant of FEV1 and PD20FEV1 at follow up were the values of these variables at diagnosis. Complete recovery of occupational asthma was observed in 7 subjects (24%), all in the non-exposed group. Latex-specific IgE did not exhibit significant changes. In conclusion latex-induced occupational asthma improves after a follow-up of 5 +/- 3 years, but a complete recovery occurs in a minority of subjects and is associated with cessation of exposure. Lung function measurements at follow up depend from their impairment at the time of diagnosis. We evaluated the impact of impermeable bed covers on asthma in asthmatics with clinically relevant house dust mite (HDM) sensitization.
                The study included 32 HDM-sensitized asthmatics in whom HDM allergy was considered as a significant factor in their asthma. They were randomized into either an intervention group whose bedding was encased with impermeable covers, or a control group who received cotton covers. Before and 3 and 6 months after encasement, dust samples were collected from the bedding and assayed for Der p 1. Clinical outcomes included quality of life, lung function, bronchial reactivity to methacholine, symptoms, medications and peak flow rates.
                Baseline Der p 1 levels in both the active and the placebo groups were comparable and high (19.2 vs 18.9 microg/g of dust). There was a significant reduction in Der p 1 levels in the active group after 6 months, but not in the placebo group (7.3 vs 21.9 microg/g of dust). Quality of life improved significantly in both the intervention and control groups, but there was no significant difference in the improvements between the groups. There was no significant change in lung function, symptoms, and requirements for medications.
                Encasement of bedding significantly reduced the Der p 1 levels. However, this was not sufficient to produce worthwhile clinical improvement in those in whom dust mite avoidance might well have been recommended as part of their clinical management.
                Copyright (c) 2006 S. Karger AG, Basel. To examine the long-term maintenance of a previously reported behavioral counseling intervention to reduce asthmatic children's exposure to environmental tobacco smoke (ETS).
                Families of asthmatic children (6 to 17 years), including at least one parent who smoked in the home, recruited from four pediatric allergy clinics.
                Participants were randomized to one of three groups: behavioral counseling to reduce ETS exposure, self-monitoring control, and usual medical care control. Counseling concluded at month 6, and the original trial ended at month 12. Two follow-up interviews occurred at months 20 and 30.
                The originally reported analysis of baseline to 12 months was reanalyzed with a more robust restricted maximum likelihood procedure. The 2-year follow-up period was analyzed similarly. Significantly greater change occurred in the counseling group than the control groups and was sustained throughout the 2 years of follow-up. Further exploratory analyses suggested that printed counseling materials given to all participants at month 12 (conclusion of the original study) were associated with decreased exposure in the control groups.
                Such long-term maintenance of behavior change is highly unusual in the general behavioral science literature, let alone for addictive behaviors. We conclude that ETS exposure can be reduced and that a clinician-delivered treatment may provide substantial benefit. As asthma is the most common chronic disease in childhood, much attention is directed towards primary prevention. Here, the clinical effectiveness of a multifaceted educational prevention was studied. A total of 476 high-risk children were recruited during the prenatal period by general practitioners and randomised to either: 1) a control group, receiving usual care; or 2) an intervention group in which families received instruction from nurses on how to reduce exposure of newborns to mite, pet and food allergens, and passive smoking. A total of 443 infants were followed-up for 2 yrs. At 2 yrs of age, the intervention group (n = 222) had less asthma-like symptoms, including wheezing, shortness of breath and night-time cough, than the control group (n = 221). No significant differences in total and specific immunoglobulin E were found between the groups. During the first 2 yrs of life, the incidence of asthma-like symptoms was similar in both groups; however, subanalysis revealed a significant reduction in the female, but not in the male, intervention group. In conclusion, the intervention used in this study was not effective in reducing asthma-like symptoms in high-risk children during the first 2 yrs of life, although it was modestly effective at 2 yrs. Follow-up is necessary to confirm whether the intervention can actually prevent the development of asthma. We have compared the bronchial responsiveness (BR) of 12 aluminum potroom workers (index group) who were relocated due to work-related asthmatic symptoms (WASTH) and 26 subjects (reference group) with WASTH who continued to work in potrooms. The subjects were examined at regular intervals during a 2-year follow-up period. BR was expressed as the log-transformed dose-response slope [Ln(DRS 5)]. The monthly change in BR (delta BR) in the index group was -4.87 x 10(-2) compared with -1.58 x 10(-2) in the reference group. After adjustment for potential confounders, the difference between the index group and the reference group was -2.39 x 10(-2) (95% CI: -4.07 x 10(-2) to -0.71 x 10(-2)), i.e. 49% of the decrease in BR in the index group could be explained by the removal from exposure. No improvement in lung function was found in the index group compared with the reference group. The results indicate that the removal of potroom workers from exposure causes a decrease in BR. Thirty-one patients with isocyanate-induced asthma were studied 6-54 months after diagnosis. Four had the same work conditions and unchanged or worse respiratory symptoms; seven had an alternative job or safer work conditions at the same work-place and suffered from mild to severe symptoms. The remaining twenty subjects were definitely removed from exposure; of these, ten (50%) remained symptomatic after being removed from exposure for an average of 19 months. Asymptomatic patients appeared to be younger and to have shorter durations of total and symptomatic exposures, while symptomatic patients were more reactive to acetylcholine at diagnosis. For patients removed from isocyanate exposure and for those re-employed at the same work-place, quality of the new work site seems to play a role in the evolution of isocyanate-induced asthma. After an average follow-up interval of three and a half years (range one to nine years), 125 patients with occupational asthma due to red cedar exposure were re-examined. Fifty patients remained in the same job. All of them continued to have asthmatic attacks requiring regular medication for relief of symptoms. They had worse lung function and ther bronchial reactivity to methacholine increased. Seventy-five patients left the industry; half of them became asymptomatic, whereas the remaining half continued to have recurrent attacks of asthma. Several factors were of prognostic significance. Those with a shorter duration of exposure as well as a shorter duration of symptoms prior to diagnosis and removal from exposure showed improvement. Those who remained symptomatic tended to be older; they had longer duration of exposure and a longer duration of symptoms prior to diagnosis. They tended to have more abnormal results of lung function studied and more marked bronchial hyper-reactivity to methacholine at the time of diagnosis. They also tended to have dual asthmatic reaction rather than late asthmatic reaction to inhalation challenge with red cedar extract. Smoking, race and degree of peripheral blood eosinophilia did not play a role in determining the outcome. Since none of these patients had symptomatic asthma before employment and since they reacted to inhalation challenge of red cedar, it could be assumed that persistent asthma in those who failed to recover is the result of their previous occupational exposure. Early diagnosis and removal from exposure were found to be associated with recovery. This study tested the efficacy of coaching to reduce environmental tobacco smoke (ETS) exposure among asthmatic Latino children.
                After asthma management education, families were randomly assigned to no additional service (control condition) or to coaching for ETS exposure reduction (experimental condition).
                The study was conducted in San Diego, California.
                Two hundred four Latino children (ages 3-17 years) with asthma participated.
                Approximately 1.5 hours of asthma management education was provided; experimental families also obtained 7 coaching sessions ( approximately 45 minutes each) to reduce ETS exposure.
                Reported ETS exposure and children's urine cotinine were measured.
                Parents in the coached condition reported their children exposed to significantly fewer cigarettes than parents of control children by 4 months (postcoaching). Reported prevalence of exposed children decreased to 52% for the coached families, but only to 69% for controls. By month 4, mean cotinine levels decreased among coached and increased among control children. Cotinine prevalence decreased from 54% to 40% among coached families, while it increased from 43% to 49% among controls. However, cotinine levels decreased among controls to the same level achieved by coached families by the 13-month follow-up.
                Asthma management education plus coaching can reduce ETS exposure more than expected from education alone, and decreases in the coached condition may be sustained for about a year. The delayed decrease in cotinine among controls is discussed. Allergic occupational asthma is frequent in farming populations. As educational interventions can improve disease management, the short-term effect of an educational intervention in asthmatic farmers was evaluated on the basis of spirometric indices and exhaled nitric oxide fraction (F(eNO)). Farmers with occupational asthma (n = 81), mostly sensitised against cow dander and storage mites, participated in a 1-day educational programme. Outcome measures were assessed at baseline and after 4-6 weeks, using F(eNO), lung function and a questionnaire. Results were compared with those of a control group without intervention (n = 24). In the educational group, the proportion of subjects reporting work-related symptoms was reduced after the intervention. The F(eNO) decreased from a geometric mean of 28.2 to 25.7 ppb, and, in subjects with an elevated (>35 ppb) baseline F(eNO) (n = 32), from 59.7 to 49.2 ppb. The corresponding changes in the control group were 25.6 versus 27.7 ppb and 49.5 versus 48.1 ppb. Spirometric results were unaltered in the two groups. Thus exhaled nitric oxide fraction, a marker of allergic airway inflammation, indicated a beneficial effect of a short-term educational intervention in farmers with occupational asthma. This suggests a potential for exhaled nitric oxide fraction in assessing the efficacy of preventive measures within a short time with higher sensitivity than spirometry. Inhalation of house dust mite (HDM) allergen may provoke attacks of asthma.
                We investigated whether a double-blind placebo-controlled community-based study aimed at reducing the HDM allergens in the bedrooms of HDM sensitive asthmatic children using the best methods available would prove beneficial to the children's health.
                The children (mean age 9.9 years, 34 boys) were recruited by a questionnaire submitted to 7386 families in a geographically-defined area of the UK. Subjects were chosen to take part in the double-blind placebo-controlled trial if they were asthmatic, skin sensitive to mites, and had mite allergen in their mattresses. Seventy children were randomly allocated to groups. In the active group, the children's bedrooms were treated with an acaricide (Acarosan) and the mattresses, pillows and duvets were encased in exclusion covers. The control group received placebo treatments.
                Forty-nine complete data sets were obtained. Applying bedding covers and Acarosan led to a median reduction of 480 ng (100%) in mite allergen on the mattress vs 215 ng (53%) reduction in placebo-treated group by 6 weeks. No evidence was found that the acaricide reduced mite allergen level. A change in bronchial reactivity to histamine was observed in the children after 6 weeks. This was not associated with any change in thrice-daily records of peak expiratory flow rate. By 24 weeks, the actively-treated children had improved forced expiratory volume in 1s (FEV1) and fewer required bronchodilator therapy or reported asthmatic symptoms than did the controls.
                The results suggest that mite removal procedures may modestly improve mite-sensitive asthmatics and could perhaps be of value in exceptionally mite-sensitive and/or highly mite-exposed individuals whose response to the attempted removal should be measured. In a school with floor moisture problems, the personnel had complaints consistent with the sick-building syndrome (SBS). Interventive measures including the laying of a ventilated floor were undertaken to eliminate the emissions. To examine if the intervention resulted in positive health effects, 34 personnel and 336 pupils were interviewed just before the intervention and also 7 months after. Also were interviewed 21 personnel and 224 pupils at an adjacent school serving as a control. Compared with the control school, the problem school showed more complaints, more general symptoms and more symptoms from the eyes, airways and skin, both among the personnel and the pupils. In the post-intervention examinations, the excess of symptoms among the personnel had almost disappeared. Among the pupils, the frequency of eye irritation was reduced but a general improvement of the other symptoms was not as obvious. However, after adjustment for a recent common cold, atopy and stress among the pupils, only one symptom ("stuffy nose") remained significantly elevated. In conclusion, the intervention was followed by positive health effects, supporting the hypothesis that emissions from building material had contributed to the excess of symptoms. A recent common cold was highly related to the symptoms and should be considered in future SBS studies. Passive smoke exposure among children is widespread in the United States; estimates suggest that almost 40% of children who are younger than 5 years live with a smoker. Few randomized studies of passive smoke exposure reduction among children have been conducted, and the impact of interventions that have been evaluated has been limited. The objective of this study was to determine whether a motivational intervention for smoking parents of young children will lead to reduced household passive smoke exposure.
                Project KISS (Keeping Infants Safe From Smoke), a theory-driven exposure reduction intervention targeting low-income families with young children, was a randomized controlled study in which participants-smoking parents/caregivers (N = 291) who had children who were younger than 3 years and who were recruited through primary care settings-were randomly assigned to either the motivational intervention (MI) or a self-help (SH) comparison condition was used. Follow-up assessments were conducted at 3 and 6 months. The MI condition consisted of a 30- to 45-minute motivational interviewing session at the participant's home with a trained health educator and 4 follow-up telephone counseling calls. Feedback from baseline household air nicotine assessments and assessment of the participant's carbon monoxide level was provided as part of the intervention. Participants in the SH group received a copy of the smoking cessation manual, the passive smoke reduction tip sheet, and the resource guide in the mail. Household nicotine levels were measured by a passive diffusion monitor.
                The 6-month nicotine levels were significantly lower in MI households. Repeated measures analysis of variance across baseline, 3-month, and 6-month time points showed a significant time-by-treatment interaction, whereby nicotine levels for the MI group decreased significantly and nicotine levels for the SH group increased but were not significantly different from baseline.
                This study targeted a large sample of racially and ethnically diverse low-income families, in whom both exposure and disease burden is likely to be significant. This is the first study to our knowledge that has been effective in reducing objective measures of passive smoke exposure in households with healthy children. These findings have important implications for pediatric health care providers, who play an important role in working with parents to protect children's health. Providers can help parents work toward reducing household passive smoke exposure using motivational strategies and providing a menu of approaches regardless of whether the parents are ready to quit.
There is very low-quality evidence that removal from exposure improves asthma symptoms and lung function compared with continued exposure.
Reducing exposure also improves symptoms, but seems not as effective as complete removal.
However, removal from exposure is associated with an increased risk of unemployment, whereas reduction of exposure is not. The clinical benefit of removal from exposure or exposure reduction should be balanced against the increased risk of unemployment. We need better studies to identify which interventions intended to reduce exposure give most benefit.