Biomedical subjects

M G Cline

Publications and source records attributed to M G Cline.

5 recordsLinked to original sources

PubMed1991

Findings before diagnoses of asthma among the elderly in a longitudinal study of a general population sample.

Forty elderly subjects who denied ever having asthma or emphysema on enrollment in a longitudinal epidemiologic study later reported consulting a doctor for asthma when they were older than 60 years of age. The average age at which the diagnosis was reported was 70.8 years, after a mean follow-up of 8.5 years. Findings on enrollment in the newly diagnosed subjects with asthma are compared with findings in the 1145 subjects who provided follow-up information when they were older than age 60 years but had never developed asthma. At the time of enrollment, most subjects later diagnosed as having asthma already had wheezing symptoms, suggesting at least a mild asthmatic state, and many subjects had impaired ventilatory function, a positive allergy skin test (especially in association with rhinitis), and blood eosinophilia. Thirty-five percent of the subjects recalled "respiratory trouble before age 16" despite denying prior asthma. The likelihood of a new asthma label was very closely related to the age-sex-standardized serum-IgE level before diagnosis. Newly diagnosed subjects with asthma demonstrated much greater rates of decline in FEV1 than control subjects or than subjects who already had known asthma on enrollment. We conclude that (1) symptoms suggesting asthma are usually present for many years before the diagnosis of the disease in elderly subjects, (2) the serum-IgE level is closely related to the likelihood of a subsequent asthma diagnosis, even in this age group, and (3) a rapid fall in lung function often occurs around the time of initial diagnosis.

Age Factors↗

PubMed1991

Characteristics of asthma among elderly adults in a sample of the general population.

This article describes the characteristics and course of asthma among subjects who were older than 65 years at the time of enrollment in a longitudinal study of a general population sample. It was present in 3.8 percent of men and 7.1 percent of women. An additional 4.1 percent of men reported having "asthma," but they also had seen a physician for "emphysema" and had smoked significantly; their "asthma" diagnosis is regarded as highly questionable. They did not show the elevated rate of allergy skin test reactivity of high serum IgE levels that were characteristic of other asthmatics. Many of the elderly asthmatics (mean age, 72 years) had severe disease with marked ventilatory impairment. There was a close relationship between the severity of wheezing complaints and impairment of the FEV1. Of the 46 patients, 48 percent reported an onset before age 40 years. There was no relationship between severity and age of onset or duration of disease. A second diagnosis of "chronic bronchitis" was reported by 46 percent of the asthmatics, but this did not delineate a distinctive group with late-onset, smoking-related disease. Death rates in the asthmatics tended to be higher than in nonasthmatics (odds ratio, 1.9; CI, 0.998 to 3.70, after stratifying by sex). Over a mean follow-up of 7.44 years, most symptoms as well as the FEV1 remained relatively stable. Chronic productive cough did tend to remit (p less than 0.01), but this was noted in the nonasthmatics as well. We estimate that no more than 19 percent of the asthmatics went into complete remission during follow-up. Most of these had mild initial symptoms; there were no remissions in subjects with severe disease at the time of entry. We concluded that asthma in the elderly is not a rare disease and may be associated with severe symptoms and chronic airways obstruction. If severe, it rarely goes into complete remission but tends to remain a severe, disabling disorder.

Aged↗

PubMed1990

Problems in defining normal limits for serum IgE.

Recommended "normal limits" for serum IgE generally assume that a single upper limit of normal can be applied to all adults. The present article describes the distribution of IgE levels in 2657 subjects in a general population sample in Tucson, Ariz. Limits of IgE defining the lower 5%, 10%, 25%, 50%, 75%, 90%, and 95% in 1569 subjects with negative allergy skin tests and without current asthma, considered a reference group, are provided by age and sex. These cutoffs are then used to compare groups with asthma and with positive allergy skin tests with the reference population. Distributions of IgE levels in these groups are vastly different, but defining an upper "limit of normal" for serum IgE is of doubtful clinical value because there is no single level of IgE that distinguishes different groups with any precision. The spread of IgE values is extremely wide in subjects with and without known allergic diseases.

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↗

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↗