"The Impact of Birth Weight on Lung Function Is Significant"

A study has found that birth weight has a greater impact on lung function than preterm birth.

Professor Jin-Ho Yoo of the Pediatric Asthma and Atopy Center at Seoul Asan Medical Center and Professor Hwan-Soo Kim of the Department of Pediatrics at Bucheon St. Mary's Hospital, Catholic University, analyzed the correlation between preterm birth, birth weight, and current lung function in 566 pediatric asthma patients in Korea. The results showed that among patients with the same gestational age, that is, the same duration in the uterus before birth, those with birth weights below the 10th percentile had significantly lower lung function indicators compared to other patients.

Professor Jin-Ho Yoo (left) from the Pediatric Asthma and Atopy Center at Asan Medical Center, Seoul, and Professor Hwan-Soo Kim (right) from the Department of Pediatrics at Bucheon St. Mary's Hospital, Catholic University

There was almost no difference in current lung function based on whether the patient was born preterm (before 37 weeks). Even among preterm infants, those with higher birth weights relative to their gestational age showed relatively better lung function.

Human lung function increases through development and growth from birth, peaks in the early twenties, and then gradually declines over time.

Children with asthma may not reach the normal peak lung function seen in healthy adults and are at greater risk of a more significant decline in lung function during aging. Among pediatric asthma patients, lower lung function not only increases the risk of asthma exacerbation but also raises the risk of developing other lung diseases such as chronic obstructive pulmonary disease (COPD) later in life.

Professor Jin-Ho Yoo of Seoul Asan Medical Center’s Pediatric Asthma and Atopy Center and Professor Hwan-Soo Kim of the Department of Pediatrics at Bucheon St. Mary's Hospital, Catholic University, established a pediatric asthma cohort of children aged 5 to 15 years receiving treatment at 19 hospitals across Korea, centered on the Korean Academy of Pediatric Allergy and Respiratory Disease’s Pediatric Asthma Research Group. They conducted this study on 566 patients.

The patients’ current lung function was analyzed using forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). FEV1 is the amount of air that can be forcibly exhaled in one second, and FVC is the total volume of air that can be forcibly exhaled after taking the deepest breath possible.

The research team first analyzed lung function differences based on preterm birth status. Among the 566 patients, 57 were premature infants born before 37 weeks of gestation, and 509 were born at full term.

The FEV1 of the premature group and the full-term group were 92.2% and 92.3% of normal, respectively. The FVC was 99.8% and 97.8% of normal, respectively, showing no significant differences in lung function indicators based on preterm birth status.

In contrast, there were significant differences based on birth weight. Using World Health Organization (WHO) criteria, the research team classified infants born at the same gestational age into low birth weight (below the 10th percentile), high birth weight (above the 90th percentile), and normal birth weight (the remaining 80%) groups, and analyzed the relationship between birth weight and current lung function.

As a result, patients born with high birth weight had an average FEV1 of 94.6% of normal, normal birth weight patients had 90.9%, and low birth weight patients had 86.4%, showing that lower birth weight was associated with significantly reduced lung function.

Similarly, FVC was 101.8% of normal in the high birth weight group, 97.2% in the normal birth weight group, and 94.3% in the low birth weight group, demonstrating significant differences according to birth weight.

Professor Jin-Ho Yoo, director of the Pediatric Asthma and Atopy Center at Seoul Asan Medical Center, said, "The degree of lung function development at birth or very early in life greatly influences the occurrence and progression of pediatric asthma, and poorer lung function increases the risk of asthma exacerbation. Currently, there is no fundamental method to improve lung function in patients with developmental lung function deficits, so parents of pediatric asthma patients born with low birth weight need to be especially cautious."

Meanwhile, this study was recently published in the international journal Respirology (IF=6.175), published by the Asian Pacific Society of Respirology.

This content was produced with the assistance of AI translation services.