Common Core Assessments in follow-up studies of adults born preterm:recommendation of the Adults Born Preterm International Collaboration

Abstract Background: Of all newborns, 1%-2% are born very preterm (VP; <32 weeks) or with very low birthweight (VLBW; ≤1500 g). Advances in prenatal and neonatal care have substantially improved their survival, and the first generations who have benefited from these advances are now entering middle age. While most lead healthy lives, on average these adults are characterised by a number of adversities. These include cardiometabolic risk factors, airway obstruction, less physical activity, poorer visual function, lower cognitive performance, and a behavioural phenotype that includes inattention and internalising and socially withdrawn behaviour that may affect life chances and quality of life. Outcomes in later adulthood are largely unknown, and identifying trajectories of risk or resilience is essential in developing targeted interventions. Joint analyses of data and maintenance of follow-up of cohorts entering adulthood are essential. Such analyses are ongoing within the Adults Born Preterm International Collaboration (APIC; www.apic-preterm.org). Joint analyses require data harmonisation, highlighting the importance of consistent assessment methodologies. Objective: To present an expert recommendation on Common Core Assessments to be used in follow-up assessments of adults born preterm. Methods: Principles of Common Core Assessments were discussed at APIC meetings. Experts for each specific outcome domain wrote the first draft on assessments pertaining to that outcome. These drafts were combined and reviewed by all authors. Consensus was reached by discussion at APIC meetings. Results: We present a recommendation by APIC experts on consistent measures to be used in adult follow-up assessments. Conclusions: The recommendation encompasses both “core” measures which we recommend to use in all assessments of adults born preterm that include the particular outcome. This will allow comparability between time and location. The recommendation also lists optional measures, focusing on current gaps in knowledge. It includes sections on study design, cardiometabolic and related biomarkers, biological samples, life style, respiratory, ophthalmic, cognitive, mental health, personality, quality of life, sociodemographics, social relationships, and reproduction

Expiratory airflow in late adolescence and early adulthood in individuals born very preterm or with very low birthweight compared with controls born at term or with normal birthweight:a meta-analysis of individual participant data

Abstract Background: Maximal expiratory airflow peaks early in the third decade of life, then gradually declines with age. The pattern of airflow through adulthood for individuals born very preterm (at <32 weeks’ gestation) or with very low birthweight (<1501 g) is unknown. We aimed to compare maximal expiratory airflow in these individuals during late adolescence and early adulthood with that of control individuals born with normal birthweight (>2499 g) or at term. Methods: We did a meta-analysis of individual participant data from cohort studies, mostly from the pre-surfactant era. Studies were identified through the Adults born Preterm International Collaboration and by searching PubMed and Embase (search date May 25, 2016). Studies were eligible if they reported on expiratory flow rates beyond 16 years of age in individuals born very preterm or with very low birthweight, as well as controls born at term or with normal birthweight. Studies with highly selected cohorts (eg, only participants with bronchopulmonary dysplasia) or in which few participants were born very preterm or with very low birthweight were excluded. De-identified individual participant data from each cohort were provided by the holders of the original data to a central site, where all the data were pooled into one data file. Any data inconsistencies were resolved by discussion with the individual sites concerned. Individual participant data on expiratory flow variables (FEV1, forced vital capacity [FVC], FEV1/FVC ratio, and forced expiratory flow at 25–75% of FVC [FEF25–75%]) were converted to Z scores and analysed with use of generalised linear mixed models in a one-step approach. Findings: Of the 381 studies identified, 11 studies, comprising a total of 935 participants born very preterm or with very low birthweight and 722 controls, were eligible and included in the analysis. Mean age at testing was 21 years (SD 3·4; range 16–33). Mean Z scores were close to zero (as expected) in the control group, but were reduced in the very preterm or very low birthweight group for FEV1 (−0·06 [SD 1·03] vs −0·81 [1·33], mean difference −0·78 [95% CI −0·96 to −0·61], p<0·0001), FVC (−0·15 [0·98] vs −0·38 [1·18], −0·25 [–0·40 to −0·10], p=0·0012), FEV1/FVC ratio (0·14 [1·10] vs −0·64 [1·35], −0·74 [–0·85 to −0·64], p<0·0001), and FEF25–75% (−0·04 [1·10] vs −0·95 [1·47], −0·88 [–1·12 to −0·65], p<0·0001). Similar patterns were observed when we compared the proportions of individuals with values below the fifth percentile. Interpretation: Individuals born very preterm or with very low birthweight are at risk of not reaching their full airway growth potential in adolescence and early adulthood, suggesting an increased risk of chronic obstructive pulmonary disease in later adulthood