Allergy Asthma Respir Dis.  2019 Apr;7(2):99-105. 10.4168/aard.2019.7.2.99.

Indoor pet ownership in infancy is a risk factor for the development of sensitization to pets and asthma in childhood

  • 1Department of Pediatrics, Pusan National University Yangsan Hospital, Pusan National University School of Medicine, Yangsan, Korea.
  • 2Department of Pediatrics, Childhood Asthma Atopy Center, Environmental Health Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
  • 3Department of Pediatrics, Mediplex Sejong Hospital, Incheon, Korea.
  • 4Department of Pediatrics, International St. Mary's hospital, Catholic Kwandong University, Incheon, Korea.
  • 5Department of Pediatrics, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
  • 6Department of Pediatrics, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
  • 7Department of Pediatrics, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
  • 8Department of Pediatrics, National Health Insurance Service Ilsan Hospital, Goyang, Korea.
  • 9Department of Pediatrics, Gachon University Gil Medical Center, Incheon, Korea.
  • 10Department of Pediatrics, Chungbuk National University Hospital, Chungbuk National University College of Medicine, Cheongju, Korea.
  • 11Department of Pediatrics, Daejeon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Daejeon, Korea.
  • 12Department of Pediatrics, Presbyterian Medical Center, Jeonju, Korea.
  • 13Department of Pediatrics, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.
  • 14Department of Pediatrics, Gwangju Veterans Hospital, Gwangju, Korea.
  • 15Department of Pediatrics, Catholic University of Daegu School of Medicine, Deagu, Korea.
  • 16Department of Pediatrics, University of Ulsan College of Medicine, Ulsan, Korea.
  • 17Department of Pediatrics, Dong-A University Hospital, Dong-A University College of Medicine, Busan, Korea.
  • 18Department of Pediatrics, Gyeongsang National University College of Medicine, Jinju, Korea.


It is controversial whether indoor pet exposure is either a risk or protective factor developing sensitization to pet allergens or asthma. Therefore, we investigated whether indoor pet ownership entails a risk for the development of asthma and sensitization in childhood.
The Panel Study of Korean Children (PSKC) is a general-population-based birth cohort study that recruited 2,078 mother-baby dyads in Korea between April and July of 2008. Among 1,577 children who were followed up in 2015, 559 underwent skin prick tests, spirometry and bronchial provocation tests using Provocholine. Having a cat or a dog and the prevalence of asthma were evaluated by using self-reported questionnaires and physicians' medical records.
During infancy, the rate of dog ownership was 4.5% (71 of 1,574) and that of cat ownership was 0.5% (8 of 1,574). Of the subjects, 7.9% (n=109) currently had at least 1 dog and 2.5% (n=34) had at least 1 cat. Pet ownership during infancy was associated with sensitization to cats or dogs (adjusted odds ratio [aOR], 4.24; 95% confidence interval [CI], 1.29-13.98), wheezing within 12 months (aOR, 5.56; 95% CI, 1.65-18.75) and current asthma (wheezing episode in the last 12 months+diagnosed asthma by physicians) (aOR, 6.36; 95% CI, 1.54-26.28). In contrast, pet ownership during the last 12 months was not associated with sensitization to cats or dogs or current asthma.
Indoor pet exposure during infancy can be critical for developing sensitization to cats or dogs and asthma in childhood. Avoidance of pet exposure in early life may reduce sensitization to cats or dogs and development of asthma.


Pets; Infant; Asthma; Allergens

MeSH Terms

Bronchial Provocation Tests
Cohort Studies
Medical Records
Methacholine Chloride
Odds Ratio
Protective Factors
Respiratory Sounds
Risk Factors*
Methacholine Chloride


  • Fig. 1. Study population. PSKC, Panel Study of Korean Children; ISAAC, International Society for Augmentative and Alternative Communication. *The rate of pet ownership from pregnancy to infancy was evaluated by a 2013 questionnaire. †2015 questionnaire was used to identify the baseline characteristics and confounders (sex, body mass index, preterm birth, possession of pet within the last 12 months, breastfeeding, secondhand smoke, parental allergic disease, history of bronchiolitis, and maternal education level).



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