Poor Asthma Control in Schoolchildren May Lead to Lower Lung Function Trajectory from Childhood to Early Adulthood: A Japanese Cohort Study

Abstract

Purpose

Although childhood asthma is a risk factor for adult lung function disorders, the correlation between childhood asthma control level and lung function growth remains unclear in Japan. The correlation between childhood asthma control and early adulthood lung function growth was investigated in this study.

Patients and Methods

We included 505 children with asthma from the Omuta City Air Pollution-Related Health Damage Cohort Program. The characteristics and lung function of girls and boys aged 6–11 years and 12–17 years were compared between poor and good asthma control groups.

Results

Among the 505 children, 214 (42.4%) showed poor asthma control. The mean percentage forced expiratory volume in 1 second predicted for girls and boys aged 6–11 years (80.2% and 79.2%, respectively) and 12–17 years (80.0% and 81.1%, respectively) in the poor control group was significantly lower than those of girls and boys aged 6–11 years (87.9% and 87.3%, respectively) and 12–17 years (88.1% and 87.8%, respectively) in the good control group. However, a linear regression model did not reveal between-group differences in the slopes of lung function growth for both sexes. Girls (24.6%, P < 0.0001) and boys (24.4%, P = 0.0026) in the poor control group had a significantly higher proportion of young adults with obstructive ventilatory patterns than girls (1.4%) and boys (8.1%) in the good control group.

Conclusion

Our findings revealed that poor childhood asthma control leaded to lung function disorders, which suggest the importance of early asthma control in school children.

Keywords:

• childhood asthma
• airflow limitation
• Japanese
• transition
• school-age children

Abbreviations

ANOVA, analysis of variance; BMI, body mass index; CI, confidence interval; COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; ICD-10 Version, International Statistical Classification of Diseases and Related Health Problems 10th Revision; SD, standard deviation; UMIN, University Hospital Medical Information Network.

Acknowledgments

The authors thank all members of the Review Board Committee of the Omuta City Air Pollution-Related Health Damage Cohort Program. Special thanks are extended to Dr. Masayuki Kawasaki, Chairman of the Review Board Committee, President of the National Hospital Organization Omuta Hospital, and Adviser for the Review Board Committee, as well as Mrs. Masami Kanamaru and Mrs. Naomi Shimomura for data management and Mr. Keiji Hirayama, Chief Manager, Department of Health and Welfare, Omuta City.

Disclosure

Prof. Tomotaka Kawayama reports grants from Novartis and lecture fees from AstraZeneca, GlaxoSmithKline (GSK), Boehringer Ingelheim, Novartis, Teijin Home Healthcare, Sanofi, Kyorin, and MeijiSaika Pharma. Dr. Takashi Kinoshita reports grants from GSK, AstraZeneca, and a lecture fee from AstraZeneca. Prof. Tomoaki Hoshino reports a grant from GSK, Novartis, and Chugai Pharmaceutical. The other authors have no potential conflicts of interest for this study.

Additional information

Funding

This work was supported by JSPS KAKENHI Grant Number JP 21K16152, Japan (J. S.).