Researchers identify several early-life factors that influence adult lung function

Lung function in 24-year-old adults was influenced by maternal perinatal BMI, birthweight, childhood asthma and childhood lean and fat mass, according to study results published in European Respiratory Journal.

Osama Mahmoud

“Our study has provided evidence for associations of several factors with early-adult lung function, in addition to the well-known factors of sex, height and race,” Osama Mahmoud, PhD, FHEA, assistant professor in data science and statistics at the University of Essex, United Kingdom, told Healio. “Our large population-based birth cohort study found that maternal smoking and BMI during pregnancy, birthweight, body composition at primary school and early onset of asthma were the most important factors on adulthood lung function among 33 factors covering sociodemographic, perinatal, childhood, environmental, lifestyle and physiological characteristics.”

Mahmoud and colleagues analyzed 7,545 individuals (51% female) from birth to age 24 years from the Avon Longitudinal Study of Parents and Children (ALSPAC) to understand what early-life factors impact lung function in early adulthood.

To account for various sociodemographic, environmental, lifestyle and physiological characteristics, researchers created a list of 33 risk factors possibly linked to decreased lung function and grouped them into one of five groups according to timing of exposure: demographic, maternal and child; perinatal; postnatal; early-childhood; and adolescence characteristics.

Researchers captured lung function at age 8, 15 and 24 years through measures of FVC, FEV₁, FEV₁/FVC and forced expiratory flow at midexpiratory stage (FEF_25-75), all standardized for sex, age and height. They then assessed the association and relative importance (RI) of all the individual characteristics for each the lung function measures using linear regression that accounted for other characteristics in both the same category and the categories before it.

Using data on associations discovered between early-life characteristics and lung function in early adulthood, researchers derived the RI of the factors using the lung function models adjusted for sex, age and height.

These models showed that characteristics associated with lower FVC included lower maternal perinatal BMI (RI = 0.6%), lower birthweight (RI = 0.5%), lower lean mass (RI = 7.7%) and higher fat mass in childhood (RI = 0.6%).

Lower birthweight (RI = 0.5%), lower lean mass (RI = 4.6%) and higher fat mass (RI = 0.5%) also influenced decreased FEV₁ in addition to having no siblings (RI = 0.5%).

A lower measure of FEV₁/FVC appeared related to maternal perinatal BMI (RI = 0.5%), maternal smoking during pregnancy (RI = 0.5%), higher lean mass (RI = 0.8%) and asthma in childhood (RI = 0.6%), according to researchers.

For FEF_25-75, childhood asthma had the greatest influence with an RI of 0.7%, followed by low lean mass in childhood (RI = 0.3%) and pre-term delivery (RI = 0.3%).

Even though every influence found was modest, when compared with the characteristics sorted into demographic, postnatal and adolescence categories, researchers found that perinatal and early-childhood characteristics demonstrated relatively larger influences on lung function in early adults.

“Our findings highlight the importance of targeting modifiable early-life risk factors and suggests potential avenues for public health interventions,” Mahmoud told Healio. “We hope that our findings will pave the way to developing predictive tools for respiratory health and reducing health care inequality by targeting early-life interventions for individuals at higher risk.”

For more information:

Osama Mahmoud, PhD, FHEA, can be reached at o.mahmoud@essex.ac.uk.