Search PubMed⌕ Search

Biomedical subjects

B Burrows

Publications and source records attributed to B Burrows.

At least 109 records · Page 6Linked to original sources
PubMed1980

The prevalence and incidence of asthma and asthma-like symptoms in a general population sample.

We have examined the prevalence of incidence of asthma and other wheezing syndromes in subjects in a longitudinal epidemiologic study. The point prevalence of asthma was 6.6%, with the highest rates occurring in children. Rates were also relatively high in older subjects, in most of whom "chronic bronchitis and/or emphysema" had been concomitantly diagnosed. Other wheezing was very common in this population sample; in most age groups, the point prevalence rates of some form of wheezing exceeded 30%. New asthma developed in 1.4% of the subjects who were followed over a period of approximately 4 yr. New attacks of shortness of breath with wheeze occurred in 10.3% of the subjects at risk over the same time period. The incidence of asthma was greatest in young children, was least in late adolescence, and increased again in early adult life. The incidence was 1.5 times greater in young boys than in young girls but was much greater in women older than 40 yr of age, perhaps reflecting the diagnostic biases of physicians. In subjects younger than 40 yr of age, onset of the disease was strongly associated with previously demonstrated allergy skin test reactivity. New disease in this age group occurred de novo, primarily within the first few years of life or during early adult life. Subjects in whom asthma developed after 40 yr of age usually had prior symptoms of chronic bronchial irritation and often had obvious spirometric abnormalities. The disease in these subjects was not associated with positive allergy skin test reactions. Because in these older subjects it does not appear possible to clearly distinguish "asthma" from "chronic bronchitis," the label "asthmatic bronchitis" appears to be a reasonable descriptive term for this syndrome.

Adolescent↗
PubMed1980

Epidemiologic observations on eosinophilia and its relation to respiratory disorders.

The percentage of eosinophils (%EOS), determined from a differential blood smear, was measured in 2,311 subjects enrolled in a general population study in Tucson, Arizona. A subgroup of 290 subjects was tested in more detail during a later evaluation in which absolute eosinophil counts, leukocyte counts, and nasal smears for eosinophils were obtained. In men, but not in women, there was a significant tendency for the %EOS to decrease with age. The highest %EOS was noted during the months of February through May, the time when most plants in this region are in bloom. Blood eosinophils were significantly related to allergy skin test reactivity, circulating IgE concentrations, several respiratory symptoms and disease diagnoses, as well as to reduced ventilatory function. Among subjects younger than 55 yr of age, however, ventilatory function was significantly low, and symptom rates increased only when there was allergy skin test reactivity in addition to eosinophilia. Neither allergy skin test reactivity nor eosinophilia alone was related to ventilatory function in this age group. Among older subjects, blood eosinophilia was associated with definite impairment of ventilatory function, regardless of skin test reactivity and independent of smoking habits. The presence of eosinophilia identified a predominantly female group of elderly nonsmokers with markedly impaired ventilatory function. These subjects appeared to fall into the clinical category of "asthmatic bronchitis".

Adolescent↗
PubMed1979

Predictors of mortality in chronic obstructive pulmonary disease. A 15-year follow-up study.

The relative usefulness of various initial findings in predicting survival is reported for 200 patients with chronic obstructive pulmonary disease who have been followed for approximately 15 years. After 5 years of follow-up, subjects 62 or more years of age showed a poorer survival rate than younger subjects. After controlling for age, the per cent predicted forced expiratory volume in 1 sec after administration of bronchodilator was the best indicator of prognosis. In subjects less than 65 years of age, the presence or absence of cor pulmonale further improved the prediction of subsequent mortality. Regardless of initial findings, however, there was wide individual variability in prognosis, and factors relating to this variability remain obscure. No difference in survival rate was noted between the 178 male patients who were enrolled in Chicago 15 years ago and the 100 similarly impaired men enrolled in Tucson approximately 7 years ago.

Aged↗
PubMed1978

Responses to isoproterenol in a general population sample.

The response of forced expiratory flow to inhalation of isoproterenol was evaluated in a general population sample of 1,063 subjects. Percentage changes in the forced expiratory volume in 1 sec and in the maximal flow measured at 50 percent of the initial expired forced vital capacity appeared to be the best indicators of responsiveness to bronchodilator. Subjects with a history of asthma more often showed responsiveness than did the remainder of the population, even when their initial function was within normal limits. Over-all, a high proportion of subjects with abnormalities in baseline forced expiratory volume in 1 sec or maximal flow after exhalation of 50 per cent of the forced vital capacity showed sufficient improvement after bronchodilator to cause their values after isoproterenol to fall within the normal range. The data suggest that responsiveness to bronchodilator aerosol may be a useful guide to the presence of bronchial reactivity in epidemiologic studies of obstructive airway diseases.

Adult↗
PubMed1977

Relation of protease inhibitor phenotypes to obstructive lung diseases in a community.

To examine the relative risk for the development of obstructive lung disease in persons heterozygous for alpha1-antitrypsin deficiency, we determined protease inhibitor phenotypes in 2944 subjects in a general community population. Phenotype M was found in 89.5 per cent, MS in 7.1 per cent, and MZ in 3.0 per cent of the population. There were two persons of phenotype Z and six of phenotype SZ. The study also included respiratory questionnaires and spirometry. There were no statistically significant differences in the prevalence of respiratory symptoms and diagnoses or of ventilatory impairment among the three major phenotype groups (M, MS and MZ), nor were there differences in the rates of deterioration of function with age or smoking. Consequently, we do not consider population screening for heterozygous alpha1-antitrypsin deficiency to be worthwhile.

Adolescent↗
PubMed1977

Quantitative relationships between cigarette smoking and chronic productive cough.

A close relationship between chronic productive cough and cigarette smoking was confirmed in an epidemiological study of airways obstructive disease in Tucson. Pack-years of smoking was closely related to symptom frequency and no threshold effect was noted. This relationship was affected by age and a history of childhood respiratory disease, but not by atopy. Among present smokers males and females did not differ significantly in their smoking habit specific rates of chronic productive cough, but males appeared to lose their symptoms less regularly than females when they quit smoking after many pack-years of cigarette use. When the relationship of smoking to chronic productive cough was removed, smoking was not significantly related to other aspects of 'chronic nonspecific respiratory disease' in this analysis.

Adolescent↗
PubMed1977

The relationship of acute respiratory illness history to the prevalence and incidence of obstructive lung disorders.

Several studies have suggested that acute respiratory illnesses (ARI) may be precursors to chronic obstructive lung diseases, as well as being exacerbations of such diseases. The relationship of retrospective and prospective data on ARI to the prevalence and incidence of obstructive lung disorders has been examined in the community epidemiologic study of obstructive diseases a longitudinal study in Tucson. It has been determined that both the previous and subsequent history of ARI are significantly associated with the prevalence and incidence of airways obstructive diseases, those diagnosed by physicians and those inferred by symptoms. Lung function impairment also appears to be associated with such illnesses. This study implicates ARI as one of the major factors associated with the etiology as well as the natural history of chronic obstructive lung disease.

Acute Disease↗
PubMed1977

Quantitative relationships between cigarette smoking and ventilatory function.

In this study of a general population sample, highly significant quantitative relationships were noted between pack-years of smoking and functional impairment. Subjects with chronic productive cough showed steeper declines in the forced expired volume in 1 sec and forced expiratory flow after exhalation of 75 per cent of the forced vital capacity (Vmax 25), but a definite inverse relationship between ventilatory function and pack-years was demonstrated even among subjects who denied any cough or sputum production. Current smoking showed no relationship to 1-sec forced expiratory volume or Vmax 25 when total pack-years were taken into account. Age appeared to be an important independent determinant of per cent predicted values only in regard to the Vmax 25 in symptomatic nonsmoking women. A history of childhood respiratory trouble was associated with a lower ventilatory function regardless of smoking habits, and for this reason such subjects have been deleted from detailed analyses of dose-effect relationships. Allergy skin test reactivity in young to middle-aged adults showed a significant additive effect to pack-years as a determinant of forced expiratory flow toward the end of the forced vital capacity, but the effect was noted only among present smokers.

Age Factors↗
PubMed1977

The relationship of childhood respiratory illness to adult obstructive airway disease.

This study of a general population sample reveals close relationships between histories of childhood respiratory disorders and pevalences of symptoms, obstructive airway diseases, and ventilatory impairment in 2,626 adults more than 20 years of age. Although a history of pediatric respiratory illness is associated with relatively mild impairment of ventilatory function in young adults, subjects with such a history shown an excessive decline in function with advancing years and with cigarette use. Because some of the data are retrospective and subject to the bias of preferential recall of childhood events, these observations cannot be regarded as definitive. However, present observations are compatible with the hypothesis that pediatric respiratory illness represents an important risk factor for the development of obstructive airway diseases in adult life. It is suggested that these childhood respiratory illnesses cause the adult lung to be unusually susceptible to the adverse effects of a variety of bronchial irritants and infectious agents.

Adolescent↗
PubMed1976

The maximal expiratory flow-volume curve. Normal standards, variability, and effects of age.

From a randomly selected population representative of the white population of Tucson, Ariz., satisfactory flow-volume data were obtained for 3,115 persons. Data from the 746 subjects who were totally free of symptoms or history of cardiorespiratory disease and who had never smoked were used in determining "normal" prediction equations for spirometric parameters and maximal expiratory flows. The maximal expiratory flow-volume curve showed considerable intersubject variability, but little change in shape of the mean maximal expiratory flow-volume curve was seen with advancing age when the effects of disease, insult, or injury were excluded.

Adolescent↗