Early life origins of breathing problems

The functioning of lungs in adulthood and the risk of developing chronic breathing problems is partly determined in childhood, according to a new study.

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease that makes it hard to breathe. It covers emphysema, chronic bronchitis, and severe asthma. COPD is chiefly caused by cigarette smoking. To determine the impact of early childhood lung functions on the possibility of developing COPD in adulthood, researchers studied 13,359 men and women, aged between 20 and 45 years participating in the European Community Respiratory Health Survey. The researchers took into consideration factors like paternal asthma, current smoking status, childhood asthma, maternal smoking and childhood respiratory infections.

It was found that 40 percent of the participants had at least one childhood disadvantage such as exposure to secondhand smoke, lung infections prior to the age of 5, having parents with asthma, or having a personal history of asthma. The researchers compared how these early life disadvantages associated with lung function tests completed 9 years apart in roughly 7,700 of these individuals.

Compared with those having no childhood disadvantages, COPD was six- and seven-times more likely, respectively, in men and women exposed to any three such factors. Exposure to two disadvantages seemed to confer five-times the COPD risk in men and doubled the risk in women.

This study indicates that adult susceptibility to COPD is partly determined early in life, and that the impact of childhood disadvantage appears to persist. Having any one or more of these factors seems to help fuel the development of COPD, later in life.

Several possible mechanisms are suggested by which childhood disadvantage might influence development of COPD. Early life factors could reduce lung growth inutero and in early childhood and prevent individuals from ever reaching the potential maximum lung function level. Also, early life environment might further influence physiological factors directly related to lung function throughout life (ie, by causing persistent inflammation. Finally, early life factors might increase susceptibility to subsequent risk factors.

This study implies that any improvement in early life environment may have large beneficial effects in the primary prevention of COPD.