Findings before diagnoses the elderly in a longitudinal population sample
of asthma among study of a general
Benjamin Burrows, MD, Michael D. Lebowitz, and Martha G. Cline, MS Tucson, Ariz.
PhD, Robert
A. Barbee, MD,
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 jindings 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-jive 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 FEV, 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. (J ALLERGY CLIN IMMUNOL 1991;88:870-7.) Key words: Asthma, geriatrics,
allergy, lung function
There have been relatively few studies on asthma among the elderly, although, based on case series and cross-sectional studies, asthma does not appear to be a rare disorder.‘-’ However, we are not aware of previous prospective studies dealing specifically with findings before NDA in older adults. Such new diagnoses are occurring with reasonable frequency in our longitudinal study of a general population sample in Tucson, Ariz.* The purpose of this article is to describe findings in subjects who denied ever having asthma at the time of enrollment in our study but reported consulting a
From the Respiratory Sciences Center, University of Arizona College of Medicine, ‘lkson, Ariz. Supported by National Heart, Lung, and Blood Institute Specialized Center for Research Grant HL14136. Received for publication March 13, 1991. Revised July 1, 1991. Accepted for publication July 2, 1991. Reprint requests: Benjamin Burrows, MD, Respiratory Sciences Center, University of Arizona College of Medicine, Tucson, AZ 85724. l/1/32310
870
Abbreviations
NDA: COPD: STpos: SOBWZ: WHZ: EOS: OR: CI: AR:
used
Newly diagnosed asthma Chronic obstructive pulmonary disease Positive allergy skin tests Attacks of shortness of breath with wheezing Any wheezing complaint or SOBWZ Eosinophil Odds ratio Confidence interval Allergic rhinitis
physician for “asthma” for the first time when they were at least 60 years of age. Their findings before an asthma diagnosis (which was first reported at an average age of 71 years) and their courses during follow-up are contrasted with findings of other subjects in the population sample. MATERIAL AND METHODS Methods of selection and study of the general population sample have been reported previously.’
The study repre-
VOLUME NUMBER
a stratified random sample of white non-MexicanAmerican households residing in Tucson in 1971 to 1972. The present study is based on findings in the 1517 subjects who provided follow-up questionnaire data after the age of 60 years. OF these subjects, 176 stated on their initial questionnaire or on some questionnaire before the age of 60 years that they had had asthma at some time in their life and were excluded from the present study. An additional 156 subjects,reported physician-confirmed “emphysema” either on enrollment or before any asthma diagnosis. Based on our cross-sectional findings,’ we are reluctant to accept NDA in a subject who already has been diagnosed as having emphysema, and such subjects are also excluded from subsequent analyses. The remaining 1185 subjects form the basis of the present study. All subjects answered “No” to the direct question, “Have you ever had asthma?‘, on their initial questionnaire. They were not included if they answered “Yes,” even if subsequent questions indicated that the disease was no longer considered to be present or that the diagnosis was never confirmed by a physician. The study consisted of 725 women (61%) and 460 men (39%) whose average age at enrollment was 64.1 ? 10.3 years. Their average total questionnaire follow-up was 11.3 -t 5.3 years, and their average follow-up after reaching their sixtieth birthday was 8.7 ?: 5.3 years. Forty subjects first reported consulting a physician for asthma after the age of 60 years. If subjects answered affirmatively lo a specific question concerning asthma on at least one follow-up questionnaire, they were considered to have NDA. In most follow-up surveys, the question took the form of “During the past year, have you seen a doctor for asthma?’ In a few of the later surveys, the question was phrased as ton the initial questionnaire, but the diagnosis was accepted only if the subject not only answered “Yes” to “Have you ever had asthma?’ but also answered “Yes” to the additisonalquestion, “During the past year, have you seen a doctor for it?” In these elderly subjects, there is always doubt about a reported diagnosis of “asthma” and whether it distinguishes a group of subjects that is different from subjects with COPD. For ithis reason,we havealsoexaminedinitial findings amongthe subjectsin the study who never reported asthmaduring follow-up but whoselast spirometrictest indicateddefinite airway obstruction.Their last test was requiredto reveal a percentpredictedFEV, of
of asthma among study of a general
Benjamin Burrows, MD, Michael D. Lebowitz, and Martha G. Cline, MS Tucson, Ariz.
PhD, Robert
A. Barbee, MD,
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 jindings 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-jive 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 FEV, 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. (J ALLERGY CLIN IMMUNOL 1991;88:870-7.) Key words: Asthma, geriatrics,
allergy, lung function
There have been relatively few studies on asthma among the elderly, although, based on case series and cross-sectional studies, asthma does not appear to be a rare disorder.‘-’ However, we are not aware of previous prospective studies dealing specifically with findings before NDA in older adults. Such new diagnoses are occurring with reasonable frequency in our longitudinal study of a general population sample in Tucson, Ariz.* The purpose of this article is to describe findings in subjects who denied ever having asthma at the time of enrollment in our study but reported consulting a
From the Respiratory Sciences Center, University of Arizona College of Medicine, ‘lkson, Ariz. Supported by National Heart, Lung, and Blood Institute Specialized Center for Research Grant HL14136. Received for publication March 13, 1991. Revised July 1, 1991. Accepted for publication July 2, 1991. Reprint requests: Benjamin Burrows, MD, Respiratory Sciences Center, University of Arizona College of Medicine, Tucson, AZ 85724. l/1/32310
870
Abbreviations
NDA: COPD: STpos: SOBWZ: WHZ: EOS: OR: CI: AR:
used
Newly diagnosed asthma Chronic obstructive pulmonary disease Positive allergy skin tests Attacks of shortness of breath with wheezing Any wheezing complaint or SOBWZ Eosinophil Odds ratio Confidence interval Allergic rhinitis
physician for “asthma” for the first time when they were at least 60 years of age. Their findings before an asthma diagnosis (which was first reported at an average age of 71 years) and their courses during follow-up are contrasted with findings of other subjects in the population sample. MATERIAL AND METHODS Methods of selection and study of the general population sample have been reported previously.’
The study repre-
VOLUME NUMBER
a stratified random sample of white non-MexicanAmerican households residing in Tucson in 1971 to 1972. The present study is based on findings in the 1517 subjects who provided follow-up questionnaire data after the age of 60 years. OF these subjects, 176 stated on their initial questionnaire or on some questionnaire before the age of 60 years that they had had asthma at some time in their life and were excluded from the present study. An additional 156 subjects,reported physician-confirmed “emphysema” either on enrollment or before any asthma diagnosis. Based on our cross-sectional findings,’ we are reluctant to accept NDA in a subject who already has been diagnosed as having emphysema, and such subjects are also excluded from subsequent analyses. The remaining 1185 subjects form the basis of the present study. All subjects answered “No” to the direct question, “Have you ever had asthma?‘, on their initial questionnaire. They were not included if they answered “Yes,” even if subsequent questions indicated that the disease was no longer considered to be present or that the diagnosis was never confirmed by a physician. The study consisted of 725 women (61%) and 460 men (39%) whose average age at enrollment was 64.1 ? 10.3 years. Their average total questionnaire follow-up was 11.3 -t 5.3 years, and their average follow-up after reaching their sixtieth birthday was 8.7 ?: 5.3 years. Forty subjects first reported consulting a physician for asthma after the age of 60 years. If subjects answered affirmatively lo a specific question concerning asthma on at least one follow-up questionnaire, they were considered to have NDA. In most follow-up surveys, the question took the form of “During the past year, have you seen a doctor for asthma?’ In a few of the later surveys, the question was phrased as ton the initial questionnaire, but the diagnosis was accepted only if the subject not only answered “Yes” to “Have you ever had asthma?’ but also answered “Yes” to the additisonalquestion, “During the past year, have you seen a doctor for it?” In these elderly subjects, there is always doubt about a reported diagnosis of “asthma” and whether it distinguishes a group of subjects that is different from subjects with COPD. For ithis reason,we havealsoexaminedinitial findings amongthe subjectsin the study who never reported asthmaduring follow-up but whoselast spirometrictest indicateddefinite airway obstruction.Their last test was requiredto reveal a percentpredictedFEV, of
