Asthma, Rhinitis, Other Respiratory Diseases
Pets, parental atopy, and asthma in adults,☆☆

https://doi.org/10.1067/mai.2002.123870Get rights and content

Abstract

Background: Studies of exposure to pets and the risk of asthma have provided conflicting results. Objective: We conducted a population-based incident case-control study to assess the relationship of current and previous pet keeping with the risk of adult-onset asthma. We also investigated whether genetic propensity as a result of parental atopy modifies these relations. Methods: From the source population of 441,000 inhabitants of a geographically defined area in South Finland, we systematically recruited, during a 2.5-year period, all new cases of asthma in 21- to 63-year-old adults and randomly selected control subjects. The clinically diagnosed case series consisted of 521 adults with newly diagnosed asthma and a control series of 932 control subjects. Information on current and past exposure to hairy pets was collected by using a self-administered questionnaire. Results: In logistic regression analysis the risk of asthma was lower among subjects with pets during the past 12 months (adjusted odds ratio [OR], 0.74; 95% confidence interval [CI], 0.57-0.96) but higher among subjects with pets more than 12 months previously (adjusted OR, 1.39; 95% CI, 1.05-1.84). Parental atopy increased the risk of asthma (OR, 1.88; 95% CI, 1.47-2.41), but there was no interaction between parental atopy and pet exposure. Conclusions: The present results are consistent with the hypothesis that both keeping furry pets and parental atopy increase the risk of asthma development in adulthood. Parental atopy does not modify the effects of pet exposure. The negative association between current pets and the risk of asthma is consistent with selective avoidance of these pets by symptomatic individuals. (J Allergy Clin Immunol 2002;109:784-8.)

Section snippets

Study design

This study was a population-based incident case-control study. The source population consisted of adults 21 to 63 years of age living in a geographically defined administrative area in South Finland with a population of 440,913 in 1997. The study was approved by the ethics committees of the Finnish Institute of Occupational Health and the Tampere University Hospital.

Definition and selection of cases

We systematically recruited all new cases of asthma, first in the city of Tampere beginning on September 15, 1997, and then from

Characteristics of case subjects and control subjects

A larger proportion of patients than control subjects were women, were young, were current smokers, were exposed to environmental tobacco smoke and to visible mold or mold odor at work, and had lower education (Table I).

. Characteristics of the study population

CharacteristicsCase subjects n (%)Control subjects n (%)
Total521932
Sex
Male175 (33.6)438 (47.0)
Female346 (66.4)494 (53.0)
Age (y)
21-29108 (20.7)141 (15.1)
30-39107 (20.5)224 (24.0)
40-49125 (24.0)254 (27.3)
50-59140 (26.9)240 (25.8)
60-6441 (7.9)

Discussion

The incident case-control study is very efficient compared with a cohort study, yielding a similar amount of information. Our study includes the largest number of new asthma cases among all the studies addressing the relations between pet keeping and the risk of development of asthma in adults. The present study corresponds to a follow-up of approximately 100,000 adults for 5 years if we assume a realistic asthma incidence of 1 case per 1000 person-years. Our results provide evidence that

References (21)

  • BJ Apelberg et al.

    Systematic review: exposure to pets and risk of asthma and asthma-like symptoms

    J Allergy Clin Immunol

    (2001)
  • HP Roost et al.

    Role of current and childhood exposure to cat and atopic sensitization

    J Allergy Clin Immunol

    (1999)
  • PG. Holt

    Infections and the development of allergy

    Toxicol Lett

    (1996)
  • B Brunekreef et al.

    Pets, allergy and respiratory symptoms in children

    Int J Epidemiol

    (1992)
  • A Siracusa et al.

    Prevalence of asthma and rhinitis in Perugia, Italy

    Monaldi Arch Chest Dis

    (1997)
  • K Noretjojo et al.

    Exposure and sensitization to cat dander: asthma and asthma-like symptoms among adults

    J Allergy Clin Immunol

    (1999)
  • E Mutius et al.

    Prevalence of asthma and atopy in two areas of West and East Germany

    Am J Respir Crit Care Med

    (1994)
  • T Laitinen et al.

    Importance of genetic factors in adolescent asthma: a population-based twin-family study

    Am J Respir Crit Care Med

    (1998)
  • JJK Jaakkola et al.

    Environmental tobacco smoke, parental atopy, and childhood asthma

    Environ Health Perspect

    (2001)
  • American Thoracic Society

    Standardization of spirometry, 1994 update

    Am J Respir Crit Care Med

    (1995)
There are more references available in the full text version of this article.

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Supported by the Ministry of Social Affairs and Health of Finland and the Finnish Work Environment Fund.

☆☆

Reprint requests: Jouni J. K. Jaakkola, MD, DSc, PhD, The Nordic School of Public Health, Box 12133, SE-402 42 Göteborg, Sweden.

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