Association between very to moderately preterm births, pulmonary function deficits and COPD at age 53: analysis of a prospective cohort study
Prematurity has been associated with reduced lung function up to age 33, but its long-term effects on lung function and chronic obstructive pulmonary disease (COPD) are unknown. To answer this question, we investigated the associations between prematurity, lung function and COPD during the sixth decade of life using data from the Tasmanian Longitudinal Health Study (TAHS).
Data were analyzed from 1445 TAHS participants. Lung function was measured at age 53. Gestational ages were very preterm (28 weeks to 1forced vital capacity [FVC]FEV11/FVC ratio, forced expiratory flow at 25–75% FVC [FEF25–75%]carbon monoxide diffusing capacity [DLCO]) and COPD (post-bronchodilator FEV11/FVC below lower limit of normal), taking into account sex, age, height, parental smoking during pregnancy, number of older siblings, age of mother at birth and the socioeconomic status of the child. Interactions with smoking and asthma have also been studied.
Of 3565 people with gestational age data from the TAHS cohort, 1445 (41%) participants were included in this study, of whom 740 (51%) were female. Compared to term birth, very to moderate prematurity was significantly associated with an increased risk of COPD at age 53 years (odds ratio 2 9 [95% CI 1·1–7·7]). Very to moderate prematurity was also associated with lower post-bronchodilator FEV11/FVC ratio (beta coefficient –2 9% [95% CI –4·9 to –0·81]), FEV11 (−190ml [–339 to –40]), DLCO (−0.55 mmol/min/kPa [–0·97 to –0·13]), and FEF25–75% (−339 mL/s [–664 to –14]). The association between very to moderate prematurity and FEV11/FVC was significant only in smokers (pinteraction=0 0082). Similar results were observed for moderate preterm births when analyzed as a separate group. Compared with term delivery, late preterm delivery was not associated with lower FEV11/FVC or COPD report.
This is the first study to investigate the effect of prematurity on lung function through middle age. Data show that very to moderate prematurity is associated with obstructive pulmonary function deficits including COPD up to the sixth decade of life and that this effect is compounded by personal smoking.
National Health and Medical Research Council (NHMRC) of Australia, European Union Horizon 2020, University of Melbourne, Clifford Craig Medical Research Trust of Tasmania, The Victorian, Queensland & Tasmanian Asthma Foundations, The Royal Hobart Hospital , Helen MacPherson Smith Trust and GlaxoSmithKline.