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At least 19 recordsLinked to original sources

Asthma Exacerbation Risk and School Asthma Readiness.

OBJECTIVES: School-based asthma management is a key facet of child asthma care. We aimed to describe the proportion of students whose schools have child-specific components of asthma care, derive a composite metric of these components ("school asthma readiness"), and assess its association with asthma exacerbations (asthma risk) in the preceding year. METHODS: Within a nested cohort of children enrolled in a larger randomized clinical trial, we assessed the baseline proportion of children whose school had elements of necessary asthma care. We then derived a "school asthma readiness" composite and used ordinal logistic regression to model the association between number of asthma exacerbations in the preceding year and the composite, accounting for demographic, clinical, and school characteristics. RESULTS: Of 202 participants aged 5 to 13 years, most identified as Black (95%) and non-Hispanic (98%), and most participants (73%) had an emergency department visit for asthma in the year before enrollment. Most students' schools (79%) had awareness of the child's asthma diagnosis, whereas fewer had reliever medications and valved holding chambers (both 31%) and asthma care plans (7%). Asthma exacerbations in the prior year were associated with a significantly higher school asthma readiness in bivariate (odds ratio [OR], 1.44 [95% CI, 1.14-1.82]; P = .002) and multivariable analysis (OR, 1.31 [95% CI, 1.02-1.7]; P = .037). CONCLUSIONS: A minority of children attended schools that were equipped to manage asthma symptoms. More past exacerbations were associated with higher school readiness, suggesting that more work is needed to support proactive asthma care in schools.

Humans

Cumulative Genetic Risk for Asthma Contributes to Disease Severity in Children with Asthma living in Urban Environments.

BACKGROUND: Childhood-onset asthma is highly heritable, with nearly 200 risk loci identified in genome-wide association studies. Aggregated polygenic risk scores can be used to quantify genetic predisposition to asthma, but their power to predict asthma severity in multi-ancestral groups has not been determined. OBJECTIVE: Our aim was to examine the predictive power of biobank-derived asthma polygenic risk scores in children with asthma living in urban environments. METHODS: We generated polygenic risk scores for asthma, derived from a large-scale genome-wide association meta-analysis, in four multi-ancestry asthma study cohorts of children living in urban environments. We assessed genetic predictions across different subphenotypes of asthma and tested for associations between genetic asthma risk and measures of asthma severity. RESULTS: Genetic asthma prediction was significantly stronger for more symptomatic asthma phenotypes (P<0.001). Polygenic risk scores were significantly higher in difficult-to-control vs. easy-to-control asthma (P=0.02). Genetic risk was also significantly associated with more frequent exacerbations (P=0.03), higher blood eosinophil levels (P=0.01), and lower lung function (P<0.001). CONCLUSION: Cumulative genetic risk for asthma is associated with disease severity and exacerbation risk in children with asthma living in urban environments.

Journal Article

"Asthma Alley": a space clustering study of asthma in Brooklyn, New York City.

A certain section of the borough of Brooklyn has sometimes been referred to as "Asthma Alley," expressing a feeling that this area in Brooklyn shows a markedly higher rate of asthma than adjacent areas. This study describes an epidemiologic method developed to determine whether the popular perception of spatial clustering of cases reflects reality. The spatial distribution of respiratory visits to the emergency room is taken as a reference against which clustering of asthma visits is compared, on the assumption that it is a good measure of the proportion of people in that area that make use of the emergency room facilities. From approximately 9,000 visits for asthma during the study period we were able to show that: (1) the differences in distribution of asthma cases among the health areas of Brooklyn are statistically significant; and (2) the health areas that show an excess of asthma visits lie along a belt east of the two hospitals and coincide with the popular impression of the location of "Asthma Alley."

Adult

Bronchial asthma in the Nigerian savanna region. A clinical and laboratory study of 106 patients with a review of the literature on asthma in the tropics.

One hundred and six asthma patients were studied in Zaria in the Nigerian savanna region. This group resembled hospital attenders in general in containing a disproportionately large number of immigrants from southern Nigeria and students undergoing higher education. Childhood asthma was rare. Asthma started after the age of 19 years in 69 per cent of patients. Twenty-seven per cent gave a history of rhinitis but none had had eczema. Twenty-two per cent gave a family history of asthma. Cutaneous hypersensitivity to house dust supported by a history of attacks being precipitated by dust was found in 41 per cent of patients. Asthma was worst in the rainy season in 45 per cent of patients. Mites were found in mattress dust samples; the mean count was 243 mites per g dust; Dermatophagoides farinae formed 86-6 per cent of the total mite population. The variability of airways obstruction averaged 50 per cent of maximum values for forced expiratory volume in the first second (FEV1) and peak expiratory flow (PEF). The median severity of airways obstruction measured as FEV1/VC per cent was four standard deviations below predicted normal. Eighty-seven per cent of patients were positive to prick skin tests with one or more allergens. The commonest reactions were to house dust (58 per cent), house dust mite (45 per cent) and Dermatophagoides farinae (44 per cent). Fifty-one per cent of a group of controls were also positive on skin testing but the pattern of responses was different from the asthmatic patients. This high proportion of reactors is explained by high allergen load. Serum IgE levels were lower in the asthmatics than in a group of healthy controls who showed the very high levels characteristic of some African populations. We suggest that the controls were protected from atopic disease by developing high blocking levels of non-specific IgE, perhaps in response to gut helminths. The clinical pattern of asthma in Zaria is compared with other countries in the tropical and temperate zones. The particular problems of treating asthma in developing tropical countries are discussed.

Adolescent

Experiments on the role of virus infections in the pathogenesis of bronchial asthma. The role of innate or acquired insufficiency or ergotropic adaptation in the mechanism of genesis of bronchial asthma.

UNLABELLED: The wide mosaic of congruent clinical and experimental observations led to the postulation that the cause of the pharmacological abnormality of the asthmatic patient, i.e. the immensely increased reactivity of the bronchial smooth muscles, is to be sought in an insufficiency of the beta-adrenergic receptor system. It is to be assumed that the so-called asthma diatheses is based inter alia on a genetically determined defect of the adenyl cyclase system. The role of previous infections of the respiratory tract in asthmagenesis should lie--following this working theory--not in a sensitization in the sense of an allergic reaction of the immediate type, but in the formation of a defective beta-adrenergic substance or in a blockade of the beta-receptor. A genetically determined innate defect of the beta-adrenergic receptors, or a defect acquired through infections of the respiratory tract, is hence likely to be the cause of the pathologically potentiated reactivity of the bronchia. It is likely that the infective stimuli--quite apart from this preparatory role--are later capable of triggering asthmatic paroxysms when the vegetative homeostasis is impaired. We know from the experiments of many authors that a blockade of the beta-receptors produced by chemical blocker substances, or by pertussis vaccine or various bacterial substances, results in a significant increase in bronchial reactivity towards histamine, serotonin, acetylcholine and other stimuli. We have shown in our experiments that heat-inactivated adeno viruses and influenza viruses also increase the anaphylactic shock reactivity and the histamine reactivity of the organism. On the basis of this working hypothesis, the pathomechanism of the asthmatic process is as follows in individual asthma forms: 1) In the 'purely" allergic asthma form, the antigen-antibody reaction that occurs after sensitization (i.e. formation of skin-sensitizing allergic antibodies of the class IgE) results in re-formation and release of slow-reacting-substances. RESULT: spasm of the bronchial muscles, asthmatic paroxysm. The expulsion of catecholamines that follows the release of slow-reacting-substances makes a decisive contribution to the reestablishment of the impaired homeostatic balance. It is to be assumed that this form of asthma both symptomatically and causally--using specific desensitization--can be influenced more easily than other forms of asthma with a more complicated pathogenic background. 2) In the second allergically determined form of asthma, we are confronted by the genetically fixed or acquired insufficiency of the beta-receptors in addition to the immunological mechanism. As a result of the innate or acquired blockade of the beta-receptive substance, or the relative dominance of the alpha-receptors, the catecholamines (that physiologically serve to maintain homeostasis) contribute to a protraction, intensification and perpetuation of the bronchial obstruction. In this way the asthmatic circulus vitiosus is complete...

Adenoviridae

Fate of occupational asthma. A follow-up study of patients with occupational asthma due to Western Red Cedar (Thuja plicata).

Thirty-eight patients with red cedar asthma proved by inhalation provocation test were studied after they had left exposure for more than 6 months. Twenty-seven patients became asymptomatic, with normal lung function (group A). Three patients had persistent chronic bronchitis with a moderate degree of airway obstruction, probably as a result of cigarette smoking (group B1). Eight patients continued to have recurrent attacks of asthma that decreased in severity after cessation of exposure, and their symptoms were probably due to previous exposure (group B2). The effect of breathing helium on maximal expiratory flow at 50 per cent of the vital capacity was studied. All except one patient in group A were responders (change in maximal expiratory flow at 50 per cent of vital capacity greater than 30 per cent). Two patients in group B1 and 2 in group B2 were nonresponders, suggesting obstruction in the small airways. All patients with red cedar asthma demonstrated bronchial hyperreactivity to methacholine to the same extent as patients with nonoccupational asthma. This hyperreactivity persisted after they left exposure, irrespective of symptoms. It is not known at present whether bronchial hyperreactivity is the predisposing factor in occupational asthma or is the result of the disease.

Adult

Incidence and significance of precipitating antibodies in occupational and non-occupational extrinsic non-atopic (type III) asthma (bronchial asthma with precipitins).

Precipitating antibodies against different organic enviromental dusts were studied in 37 patients with suggestive symptoms of nonatopic bronchial asthma, comparatively with a group of 4 patients with atopic asthma and with a group of asymptomatic subjects, exposed to the same organic dusts as the majority of patients. Precipitins were found present in over 75% of the sera from patients with infectious type non-atopic asthma and were associated with positive semidelayed type skin tests as well as with positive bronchial provocation tests a few hours after antigen inhalation. No precipitins were found in the sera from patients with atopic asthma. Precipitating antibodies were also found but in lower percentages (30%) and at lower titers, in clinically asymptomatic subjects who were occupationally exposed to the respective antigens. It was demonstrated that the presence of precipitins in the sera of patients with bronchial asthma is a valuable diagnostic element which confirms the clinical and anamnestic data. The pathogenic role of precipitins is not yet clear. It might be related to the amount of these precipitins in the serum.

Antigens

A multifactorial study of patients with asthma. Part 2: air pollution, animal dander and asthma symptoms.

As part of a multifactorial computer-assisted study of patients with asthma, the relationship between air pollution, animal dander and asthma symptoms was evaluated. No association was found between four major air pollutants (carbon monoxide, ozone, nitrogen oxides and sulfur dioxide) and asthma symptoms. Patients who owned cats and dogs reported more severe asthma symptoms (p less than .01) than patients who did not own cats and dogs. The evaluations completed to date indicate that daily exposure to cats and dogs accounts for more of the asthma symptoms differences between patients than daily exposure to air pollutants.

Adolescent

80% of patients with intrinsic asthma are homozygous for HLA W6. Is intrinsic asthma a recessive disease?

Of 26 patients with intrinsic asthma, 21 (81%) were homozygous for the histocompatibility antigen HLA-W6. Also, half the patients had complement defects, in particular low levels of C2. This is the first indication of a strong genetic component in intrinsic asthma, apart from that already known from family studies. These findings suggest that intrinsic asthma may be a recessive disease.

Asthma

Panic-fear research in asthma and the nuclear conflict theory of asthma; similarities, differences and clinical implications.

Recent research with the MMPI panic-fear scale has identified personality traits implicated in the psychological maintenance of the medical intractability of asthma. Intensity of prescribed medication, length of hospitalization, and rates of rehospitalization have been found to relate to MMPI panic-fear scores independent of the objective medical severity of the illness as indexed by longitudinal pulmonary functions. In the present study, MMPI panic-fear scores are related to separation and protection conflicts arising in childhood. While the nuclear conflict theory of asthma maintains that such conflicts occur in nearly all asthmatics and form a genetic component of the asthma, the present study finds that childhood separation and protection conflicts occur in a minority of patients, but may be instrumental in maintaining the medical intractability of the illness.

Adolescent

Bacterial precipitins and their immunoglobulin class in atopic asthma, non-atopic asthma, and chronic bronchitis.

In a study of groups of patients with atopic (extrinsic) asthma, non-atopic (intrinsic) asthma, and chronic bronchitis, no difference could be detected in the numbers having precipitating antibodies against species specific antigens from Staphylococcus aureus or Streptococcus pneumoniae compared to suitably matched control subjects. Precipitating antibodies against species specific antigens from Haemophilus influenzae, demonstrated in this investigation by double diffusion in agar gel, were found much more frequently in patients with chronic mucopurulent or obstructive bronchitis (50%) than in either asthmatic subjects (6%) or normal controls (6%) (P = less than 0.0005). While the precipitating antibody demonstrated in these patients against the extracts of Str. pneumoniae and Staph. aureus was in the IgG class alone, IgM and IgA antibody were detected against the species specific but not the non-species specific antigens of H. influenzae. These results underline the importance of H. influenzae as an infecting agent in chronic bronchitis and suggest that the finding of precipitins against the species specific H1 and H2 antigens of this bacterium denotes infection either concurrently or in the recent past. There is no evidence to suggest from this study that infection with Staph. aureus, Str. pneumoniae or H. influenzae is any more common in asthmatics as a group compared to controls or between patients with the non-atopic (intrinsic) and atopic (extrinsic) form of the disease.

Adolescent

[Drug prevention of bronchial asthma: inhibition of histamine and exercise-induced asthma by a new anti-anaphylactic oral preparation (ketotifen) (author's transl)].

The protective anti-asthmatic effect of a new anti-allergic drug with histaminolytic and anti-anaphylactic properties was tested in various controlled clinical studies of induced bronchospasm in asthmatic patients (provocation tests using a histamine aerosol, and exercise-induced asthma using a bicycle ergometer). The drug, ketotifen (a cycloheptathiophene derivative) was compared with a classical antihistaminic (clemastine) and a known cell stabiliser (disodium cromoglycate). In both models ketotifen provided significant protection.

Adult

Asthma in adults III: occupational asthma.

Recognition of the disease may be difficult, since symptoms may be atypical and a temporal association with exposure is often obscure. Attention is given to the ways of differentiating the truly allergic in origin from other types of occupational asthma.

Air Pollutants, Occupational

Discriminant analysis of bronchial asthma by linear discriminant function with parameters of flow-volumes: discriminant analysis of bronchial asthma in young male non-smokers.

With the parameters of a flow-volume and a volume-time curve, the discriminant analysis of bronchial asthma is described. The subjects were classified into three groups (healthy adults, mild asthmatic patients and moderates ones). The difference of the mean vectors of the parameters of the three groups was made clear by the selection methods of the discriminant analysis between any two of the groups both with 6 parameters (%FVC, FEV1.0%, peak flow rate (PF), flow rate at 50% of FVC (V50), flow rate at 25% of FVC (V25), and V50/V25) and with 8 (6 parameters mentioned above and V75, V10). Forced expiratory volume in 1 second percent (FEV1.0%) or V50 was selected at the first step with 6 parameters, and V75 was selected at the first step with 8 parameters. Probabilities of misclassification with 8 parameters were lower than those with 6 ones and the probability of misclassification at the discriminant analysis between healthy adults and mild asthmatic patients with 8 parameters was 15.75% at the final step.

Adult

Menaquinone (vitamin K2) therapy for bronchial asthma. II. Clinical effect of menaquinone on bronchial asthma.

A series of 191 patients with bronchial asthma were treated with menaquinone for not less than one year to investigate the clinical effects of the drug. The clinical effect may be summarized as follows: 1) The therapy with menaquinone only gave an effective rate oo 90.9% (a markedly effective rate of 42.4%) in mild patients, an effective rate of 86.7% (a markedly effective rate of 30.0%) in moderate patients, and effective rate of 72.7% (a markedly effective rate of 27.3%) in severe patients; namely, considerably a high effective rate was attained by the therapy in the respective patients. 2) The therapy with menaquinone, in conjunction with hyposensitization therapy, gave an effective rate of 100% (a markedly effective rate of 33.3%). 3) The double blind study of the clinical effects of menaquinone revealed that placebo used in the study was effective on only 16.7% of the patients treated with it, and that the incidence of recurrence due to withdrawal of meaquinone therapy tended to be low in the patients treated with the drug for a long period of time.

Asthma