Search PubMed⌕ Search

Biomedical subjects

W Kaltenborn

Publications and source records attributed to W Kaltenborn.

9 recordsLinked to original sources

Peak expiratory flow from maximum expiratory flow volume curves in a community population: cross-sectional and longitudinal analyses.

The data from a longitudinal population study in Tucson, Arizona, were used to describe the development and decline with age of the peak expiratory flows (PEF) from maximum expiratory flow-volume (MEFV) curves derived using a computer-linked pneumotachometer. Subjects had performed at least one technically acceptable MEFV test in 9 of the first 11 surveys (1972-1989). There were 2,724 subjects with adequate MEFV curves, and thus PEF, in the first survey, but only 1315 in the 11th survey. The subjects were stratified based on responses to questionnaires into nonsmoking healthy subjects and others. The PEF were analysed cross-sectionally and longitudinally using data from the 6th-11th surveys (1979-1989). For longitudinal analysis, the reference population had 397 males with 1,153 observations, and 534 females with 1,700 observations. The resulting equations were compared, evaluating differences between the longitudinal and cross-sectional equations, and between reference and nonreference longitudinal populations. The results show that there were effort-dependent effects in absolute values of PEF, even after editing. Nevertheless, as with most MEFV measures in reference populations, PEF had an early increase in the rate of development, followed by a plateau phase, followed by a constant rate of decline. The ages at which changes in growth rates of PEF occurred differed by gender. The longitudinal data in adults showed a less steep decline with age compared to the cross-sectional data, as found previously for the other MEFV variables. Males in the nonreference group did not reach the same maximum level and had a steeper decline throughout adult life than did males in the reference group; females were similar. Asthmatics of both genders had slightly greater declines compared to the other nonreference subjects.

Adolescent↗

A longitudinal study of serum IgE in a community cohort: correlations with age, sex, smoking, and atopic status.

A number of factors, including age, sex, smoking habits, and atopic status have been reported in cross-sectional studies to influence levels of serum IgE. We have examined the effects of these variables on serum IgE in a community population cohort of 1109 subjects during a longitudinal study in which two serum samples were obtained 8 years apart from each subject. For the entire cohort, mean serum IgE level changed little during the follow-up period (28.9 versus 26.0 IU/ml). Most of the decreases were observed in children and young adults. Subjects more than the age of 35 years demonstrated no systematic change in serum IgE levels. By the end of follow-up (when there were few subjects still less than 16 years of age), significant relationships of IgE to age could no longer be demonstrated in nonatopic subjects. Also, in the nonatopic subjects of this cohort, there were no significant differences in IgE levels between the sexes. Among atopic subjects, there was a clear tendency for IgE to decrease with age, with atopic women more than 35 years of age demonstrating greater declines in IgE levels during follow-up than men of comparable age. The IgE levels in atopic male subjects were significantly higher than in atopic female subjects after the age of 35 years. Smoking was associated with an elevation in serum IgE. In this cohort, the smoking effect appeared to be limited to male subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Longitudinal changes in allergen skin test reactivity in a community population sample.

A cohort of 1333 subjects, aged 3 years and older, was followed for a mean of 8.1 years to assess changes in allergen skin test reactivity. The overall prevalence of reactivity to the five antigen mixtures was 39.1% during the initial survey and 50.7% after the follow-up period. The greatest increase in prevalence occurred among children and teenagers (22.2% and 19.5%) with only minimal increases after the age of 65 years (6.0%). No difference in prevalence between male and female subjects was apparent, either initially or at the end of the follow-up period. In-migration to the Tucson area was a major factor in determining changes in reaction prevalence. Among subjects more than 35 years of age, recent in-migrants accounted for most of the increased prevalence. Comparisons of atopy among consistent smoking groups confirmed the previous observation that smokers are less atopic than either nonsmokers or exsmokers, probably because of a self-selection process. In contrast, exsmokers were generally the most atopic, both initially and at the end of the longitudinal observation period. The high overall prevalence of allergen reactivity in this population is believed to be due in large measure to high year-round concentrations of multiple aeroallergens in the Tucson environment.

Adult↗

Sex differences in growth patterns of the airways and lung parenchyma in children.

Seventeen boys and 19 girls, 8-15 yr in age, were studied to ascertain, in the two sex groups, the predictors of airway size [assessed by measurement of tracheal cross-sectional area (CSA) and maximal expiratory flows (Vmax)] and the relative rates of growth of the major divisions of the airways and lung parenchyma. In boys, total lung capacity (TLC) accounted for 77% of the variance of CSA and for 66% of the variability of Vmax. In contrast, somatic growth and maturation in girls accounted for only 45% of the variance of CSA and for 64% of the variability of Vmax; TLC was relatively unimportant. In boys, but not in girls, TLC-corrected CSA was significantly and inversely related to height and to TLC. In girls, TLC-corrected Vmax at 50 and 75% of forced vital capacity were directly related to height. These observations suggest different patterns of airway-parenchymal-somatic growth relationships in the two sexes. Furthermore, parenchymal growth appears to be the best determinant of airway growth in boys. In girls, other factors, perhaps genetic in nature, besides growth of parenchyma, may help determine airway size.

Adolescent↗

Allergen skin-test reactivity in a community population sample: correlation with age, histamine skin reactions and total serum immunoglobulin E.

Allergen skin reactivity to 14 common local antigens was studied in a community population sample. Differences in the prevalence of positive reactions were related to both the specific antigen itself and the age of the subjects. For most allergens, peak prevalence occurred in the 20- to 34-yr age group, falling thereafter with increasing age. The frequency distribution of reactions revealed a bimodal curve, peaks occurring among nonreactors and those with eight positive reactions out of the 14 tests that were applied. The major contributor to this age--skin test relationship was the level of total serum IgE that was highest in young people and decreased progressively with age. Histamine skin reactions, which were smallest in younger subjects compared with all three older age groups, also contributed to the age-related prevalence of allergen skin-test reactions.

Adolescent↗

Different mechanical properties of the lung in boys and girls.

Partial (PEFV) and maximal (MEFV) expiratory flow-volume curves were obtained on 47 healthy children, 3 to 13 yr of age, while they breathed air or a helium-oxygen (He-O2) gas mixture. Girls had significantly higher (p less than 0.02) flows at FRC (Vmax FRC) on the air-MEFV curves than on the air-PEFV curves, whereas boys had similar flows on both curves. There was also a significant (p less than 0.04) relationship between the inspiratory volume (before initiating a PEFV curve) and Vmax FRC (on PEFV curves) for the girls but not for the boys. No difference in Vmax FRC (PEFV) and Vmax FRC (MEFV) were observed for either sex when He-O2 was breathed. These observations suggested that girls, with a deep inspiration, can increase their maximal flows, possibly by altering the tone of their airways. In addition, comparison of the air and He-O2 data suggested that girls may tend to dilate preferentially their larger airways with a maximal inspiration. Boys may generally be unable to do this. Such possible sex differences in the mechanical properties of the lung may relate to the different prevalence rates for severe lower respiratory tract illnesses and asthma in the 2 sexes.U

Adolescent↗

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↗