Journal Scan: Recent Influential Articles in Pulmonary Medicine
Editor's Note:This Journal Scan presents a review of important articles in pulmonary medicine. Here are summaries of some important findings from Journal of Allergy and Clinical Immunology, Pediatrics, and The New England Journal of Medicine. Links to the article abstracts are also provided. (Access to full-text articles usually requires registration at the specific journal's Web site.)
1. Anderson SD, Kippelen P. Airway injury as a mechanism for exercise-induced bronchoconstriction in elite athletes. J Allergy Clin Immunol. 2008;122:225-235.
We have known for hundreds of years that nearly all patients with asthma will have worse symptoms when they exercise. In addition, we have also known that some patients appear to have asthma symptoms only when they exercise. Most patients relate that their symptoms are especially bothersome if they exercise in cold, dry air. Contrasting theories regarding the pathogenesis of this condition have existed, with some researchers postulating that airway water loss was the primary trigger of exercise-induced bronchospasm (EIB), while others felt that airway cooling was the underlying mechanism. We now know that airway cooling is not necessary, since severe EIB may occur with inspiration of warm, dry air.
These investigators note that airway dehydration (ie, evaporative water loss from the bronchial wall) is now known to trigger the release of multiple mediators, including prostaglandins, leukotrienes, and histamine. Exposure to these substances may trigger smooth muscle contraction and changes in vascular permeability. These authors propose that exudation of bulk plasma on a repeated basis may actually damage the airways; they propose that repeated exercise in cold, dry air may actually be a cause of asthma. They cite the fact that elite winter athletes do not react to inhaled methacholine challenge with the same frequency as elite athletes with primarily summertime/warm weather exercise. Sputum analysis looking at cellular infiltrates may vary between these 2 groups as well. It is also now clear that some patients with exercise-induced bronchospasm may have a positive exercise test but a negative methacholine challenge test. What is the take-away? Exercise-induced asthma may actually be a spectrum of diseases, and the mechanism of EIB may be somewhat different in those who primarily exercise in cold, dry air (eg, cross-country skiers) vs those exercising primarily in warmer climates.
Abstract
2. Bender BG, Bartlett SJ, Rand CS et al. Impact of interview mode on accuracy of child and parent report of adherence with asthma-controller medication. Pediatrics. 2007;120:e471-477.
These investigators studied 104 asthmatic children who were being treated with inhaled corticosteroids and evaluated medication compliance using 3 different report formats: a computer-assisted self-interview; a face-to-face interview with research staff; and a pencil-and-paper written questionnaire. At 4 monthly visits, parents and children were asked to report medication compliance over both the short and longer term. Their answers were compared to an electronic monitor to assess accuracy. The results showed dismal compliance, and, even more concerning, they demonstrated dramatic overreporting of compliance. For example, in about a third of patients, the inhaler was never used once, yet full compliance with the medication was reported. Even in the most accurate mode of reporting (children reporting their medication use over the last day), the reports were accurate only about half the time. Although we all think that our patients always follow our instructions (compared with everyone else's patients who are noncompliant with their meds), the data would argue otherwise. It is wise to have follow-up calls to remind patients and their parents of the importance of compliance with inhaled corticosteroids. It is also important to remember that improved compliance with inhaled corticosteroids is associated with fewer asthma hospitalizations, fewer urgent care visits, better quality of life, and a substantially lower risk of having a fatal asthma attack.
Abstract
Full Text
3. Zutavern A, Brockow I, Schaaf B, et al. Timing of solid food introduction in relation to eczema, asthma, allergic rhinitis, and food and inhalant sensitization at the age of 6 years: results from the prospective birth cohort study LISA. Pediatrics. 2008;121:e44-52.
For a number of years, recommendations have been made to delay the introduction of solid food for the first 4-6 months of life, with a goal of decreasing the risk of developing atopic disease. Of note, there has been little scientific support for this recommendation. This is one of several recent studies to show that these recommendations may be without merit. This German study of over 2000 healthy-term infants used detailed parental questionnaires to evaluate the timing of solid food introduction with the incidence of atopic disease (eczema, asthma, allergic rhinitis, food allergy, and inhalant allergen sensitivity) by the age of 6 years. Zutavern and colleagues found that delaying the introduction of solid foods until after the age of 4-6 months did not reduce the overall odds of having any of these atopic diseases by age 6 years. Subanalysis of one group of children (those without early skin and allergic symptoms) showed that those with a more diverse diet during the first 4 months of life had a higher rate of eczema. Some data suggested that those children who had later introduction of solid food showed a tendency towards an increased incidence of food allergy, but the authors were not sure that this was a true association. This should be studied further. In summary, the authors concluded that delaying the introduction of solid foods does not reduce the risk of asthma, allergic rhinitis, or allergic sensitization by the age of 6 years. The relationship between solid food introduction and eczema is less clear. As these data accumulate, the current recommendations regarding the timing of introduction of solid food may change.
Abstract
Full Text
4. McCreanor J, Cullinan P, Nieuwenhuijsen MJ, et al. Respiratory effects of exposure to diesel traffic in persons with asthma. N Engl J Med. 2007;357:2348-2358.
In many regions of the United States, it is necessary to have automobile emissions measured by the Department of Environmental Quality in order to renew the vehicle's license and registration. If the emissions are too high, then the vehicle is not licensed until it is serviced and will pass the test. In the past, there has not been the same kind of requirements for diesel vehicles. Many have felt that much of the diesel exhaust was simply carbon particles, and so the health effects should be minimal. We are now realizing that diesel exhaust may have multiple health effects, especially for those with allergic diseases or asthma.
This study, which was done in London, looked at the effects of "real world" exposure to diesel exhaust in patients with asthma. McCreanor and colleagues compared exposure to air in a park (without vehicles) with exposure along a street with significant diesel exhaust levels. Exposure to fine and ultrafine particles, elemental carbon, and nitrogen dioxide was significantly higher near the street compared with the park. Forced expiratory volume in 1 second (FEV-1) fell over 6% along the street, and sputum markers of neutrophilic inflammation were also higher in those with higher diesel exhaust exposure. Decreases in FEV-1 were even higher in those with moderate asthma.
This is one of a number of recent studies demonstrating that exposure to diesel exhaust can worsen asthma and allergic disease. Other studies have suggested that there may be interactions between subcomponents of diesel exhaust and immunoglobulin E levels. Much further work needs to be done in this area.
Abstract
Full Text
Editor's Note:This Journal Scan presents a review of important articles in pulmonary medicine. Here are summaries of some important findings from Journal of Allergy and Clinical Immunology, Pediatrics, and The New England Journal of Medicine. Links to the article abstracts are also provided. (Access to full-text articles usually requires registration at the specific journal's Web site.)
1. Anderson SD, Kippelen P. Airway injury as a mechanism for exercise-induced bronchoconstriction in elite athletes. J Allergy Clin Immunol. 2008;122:225-235.
We have known for hundreds of years that nearly all patients with asthma will have worse symptoms when they exercise. In addition, we have also known that some patients appear to have asthma symptoms only when they exercise. Most patients relate that their symptoms are especially bothersome if they exercise in cold, dry air. Contrasting theories regarding the pathogenesis of this condition have existed, with some researchers postulating that airway water loss was the primary trigger of exercise-induced bronchospasm (EIB), while others felt that airway cooling was the underlying mechanism. We now know that airway cooling is not necessary, since severe EIB may occur with inspiration of warm, dry air.
These investigators note that airway dehydration (ie, evaporative water loss from the bronchial wall) is now known to trigger the release of multiple mediators, including prostaglandins, leukotrienes, and histamine. Exposure to these substances may trigger smooth muscle contraction and changes in vascular permeability. These authors propose that exudation of bulk plasma on a repeated basis may actually damage the airways; they propose that repeated exercise in cold, dry air may actually be a cause of asthma. They cite the fact that elite winter athletes do not react to inhaled methacholine challenge with the same frequency as elite athletes with primarily summertime/warm weather exercise. Sputum analysis looking at cellular infiltrates may vary between these 2 groups as well. It is also now clear that some patients with exercise-induced bronchospasm may have a positive exercise test but a negative methacholine challenge test. What is the take-away? Exercise-induced asthma may actually be a spectrum of diseases, and the mechanism of EIB may be somewhat different in those who primarily exercise in cold, dry air (eg, cross-country skiers) vs those exercising primarily in warmer climates.
Abstract
2. Bender BG, Bartlett SJ, Rand CS et al. Impact of interview mode on accuracy of child and parent report of adherence with asthma-controller medication. Pediatrics. 2007;120:e471-477.
These investigators studied 104 asthmatic children who were being treated with inhaled corticosteroids and evaluated medication compliance using 3 different report formats: a computer-assisted self-interview; a face-to-face interview with research staff; and a pencil-and-paper written questionnaire. At 4 monthly visits, parents and children were asked to report medication compliance over both the short and longer term. Their answers were compared to an electronic monitor to assess accuracy. The results showed dismal compliance, and, even more concerning, they demonstrated dramatic overreporting of compliance. For example, in about a third of patients, the inhaler was never used once, yet full compliance with the medication was reported. Even in the most accurate mode of reporting (children reporting their medication use over the last day), the reports were accurate only about half the time. Although we all think that our patients always follow our instructions (compared with everyone else's patients who are noncompliant with their meds), the data would argue otherwise. It is wise to have follow-up calls to remind patients and their parents of the importance of compliance with inhaled corticosteroids. It is also important to remember that improved compliance with inhaled corticosteroids is associated with fewer asthma hospitalizations, fewer urgent care visits, better quality of life, and a substantially lower risk of having a fatal asthma attack.
Abstract
Full Text
3. Zutavern A, Brockow I, Schaaf B, et al. Timing of solid food introduction in relation to eczema, asthma, allergic rhinitis, and food and inhalant sensitization at the age of 6 years: results from the prospective birth cohort study LISA. Pediatrics. 2008;121:e44-52.
For a number of years, recommendations have been made to delay the introduction of solid food for the first 4-6 months of life, with a goal of decreasing the risk of developing atopic disease. Of note, there has been little scientific support for this recommendation. This is one of several recent studies to show that these recommendations may be without merit. This German study of over 2000 healthy-term infants used detailed parental questionnaires to evaluate the timing of solid food introduction with the incidence of atopic disease (eczema, asthma, allergic rhinitis, food allergy, and inhalant allergen sensitivity) by the age of 6 years. Zutavern and colleagues found that delaying the introduction of solid foods until after the age of 4-6 months did not reduce the overall odds of having any of these atopic diseases by age 6 years. Subanalysis of one group of children (those without early skin and allergic symptoms) showed that those with a more diverse diet during the first 4 months of life had a higher rate of eczema. Some data suggested that those children who had later introduction of solid food showed a tendency towards an increased incidence of food allergy, but the authors were not sure that this was a true association. This should be studied further. In summary, the authors concluded that delaying the introduction of solid foods does not reduce the risk of asthma, allergic rhinitis, or allergic sensitization by the age of 6 years. The relationship between solid food introduction and eczema is less clear. As these data accumulate, the current recommendations regarding the timing of introduction of solid food may change.
Abstract
Full Text
4. McCreanor J, Cullinan P, Nieuwenhuijsen MJ, et al. Respiratory effects of exposure to diesel traffic in persons with asthma. N Engl J Med. 2007;357:2348-2358.
In many regions of the United States, it is necessary to have automobile emissions measured by the Department of Environmental Quality in order to renew the vehicle's license and registration. If the emissions are too high, then the vehicle is not licensed until it is serviced and will pass the test. In the past, there has not been the same kind of requirements for diesel vehicles. Many have felt that much of the diesel exhaust was simply carbon particles, and so the health effects should be minimal. We are now realizing that diesel exhaust may have multiple health effects, especially for those with allergic diseases or asthma.
This study, which was done in London, looked at the effects of "real world" exposure to diesel exhaust in patients with asthma. McCreanor and colleagues compared exposure to air in a park (without vehicles) with exposure along a street with significant diesel exhaust levels. Exposure to fine and ultrafine particles, elemental carbon, and nitrogen dioxide was significantly higher near the street compared with the park. Forced expiratory volume in 1 second (FEV-1) fell over 6% along the street, and sputum markers of neutrophilic inflammation were also higher in those with higher diesel exhaust exposure. Decreases in FEV-1 were even higher in those with moderate asthma.
This is one of a number of recent studies demonstrating that exposure to diesel exhaust can worsen asthma and allergic disease. Other studies have suggested that there may be interactions between subcomponents of diesel exhaust and immunoglobulin E levels. Much further work needs to be done in this area.
Abstract
Full Text