Protocol for ECHO study – longitudinal study investigating the impact of maternal E-cigarette use

Colleagues from UCD School of Medicine, The Coombe Hospital, Rotunda Hospital, The National Maternity Hospital, Children’s Health Ireland (CHI), University of Nottingham and the Royal College of Surgeons in Ireland (RCSI), have published the protocol for the ECHO study, an ambitious longitudinal study that aims to investigate the impact of maternal E-cigarette use during pregnancy on obstetric, neonatal, and infant outcomes.

Congratulations to UCD School of Medicine’s Associate Prof Anne Doolan, Associate Prof Shane Higgins, Prof Cecily Kelleher, Associate Prof Jennifer Walsh, Prof Des Cox, and to all those involved across other UCD Schools and affiliated health entities.

The ECHO study is funded by Children's Health Foundation and Research Ireland through the Frontiers for the Future programme.

The article is titled ‘The impact of electronic cigarettes on pregnancy and childhood health outcomes: the ECHO study—a protocol for a multicentre, prospective, observational, cohort’.

Abstract

Background

Stopping cigarette smoking in pregnancy positively impacts on the incidence of preterm birth, intrauterine growth restriction, and stillbirth. Electronic cigarettes (E-cigarettes) are viewed by some women as a lower risk alternative to tobacco smoking during pregnancy and are cautiously endorsed in some parts of the UK to support smoking cessation(1), however, robust, high-quality data on the impact of E-cigarettes on pregnancy and childhood health outcomes are lacking.

Objective

The objective of the ECHO study is to investigate the impact of maternal E-cigarette use during pregnancy on obstetric, neonatal, and infant outcomes.

Methods

Pregnant women attending three, large, standalone, urban, university, maternity units in Dublin, Ireland, will be invited to take part in this prospective, multicentre, observational cohort. Smoking and vaping patterns will be assessed using digital patient questionnaires. Objective assessment of breath carbon monoxide and urine cotinine levels will accurately determine exposure status at pre-specified timepoints. A third trimester ultrasound will assess growth and fetal dopplers across all groups. Postnatally, infants will undergo anthropometric measurements and developmental checks. A subgroup of 150 randomly selected infants will be assessed with the Bayley’s Scales of Infant and Toddler Development.

Discussion

Nicotine-containing E-cigarettes are addictive and their long-term impact on pulmonary, cardiovascular, and neurological function on developing humans is undetermined. This study is ambitious as it aims to longitudinally assess the outcomes of the mother/baby dyad, examining the impact of vaping on pregnancy, neonatal and infant health, growth and neurocognitive outcomes.

Key objectives

The ECHO study has four primary objectives described below:

• The primary obstetric objective is to establish whether infants born to women who vape are at a higher or lower risk of adverse outcomes in pregnancy compared to infants of combustible cigarette smokers and non-smokers.
• The primary neonatal objective is to assess anthropomorphic variation, if any, in newborn babies born to vapers in comparison to smokers and controls. The primary paediatric objective is to establish whether parent-reported and doctor-confirmed wheeze and/or asthma occurs more frequently in children exposed to vaping in utero compared with children of combustible cigarette smokers and non-smokers.
• The primary neurocognitive objective is to assess if there are significant differences in neurocognitive outcomes between the infants of a women who vape compared to infants of women who used combustible cigarette smokers and non-smokers.
• Globally, we aim to correlate, obstetric, neonatal, pulmonary, growth and neurocognitive differences, if any, to quantitative levels of cotinine excreted in maternal urine at in the third trimester.

To read the full article, see here.