Adults born preterm or early term have an increased risk of early adult mortality
According to a new Nordic study there’s a higher risk of young adult death from all causes and from chronic diseases in individuals born before full gestation. Excess mortality for preterm born adults was two-fold compared to term-born for: cardiovascular diseases, chronic lung disease and diabetes.
The study, which is the largest study to date, includes 6.2 million people and was led by researchers from the Norwegian University of Science and Technology (NTNU) in Norway with Karolinska Institutet (KI) in Sweden, University of Copenhagen in Denmark and the Finnish Institute for Health and Welfare (THL) in Finland.
The researchers included children born in Norway, Sweden, Denmark and Finland between 1967 and 2002, and followed them for cause of death through 2017 to a maximum age of 50, using national registers from the four countries. Data from the Medical Birth Registries (MBRs) in each country were linked with data from the respective national Causes of Death Registry. 5% were born preterm (before week 37, including 1.5% born before week 34). Relative risk of mortality in categories of gestational age was compared to children born week 39-42.
Those born before 34 weeks had 1.4-fold higher all-cause mortality than those born full term, before 39 and 41 completed weeks of pregnancy. For those born at 34 to 36 completed weeks, all-cause mortality was 1.2-fold and for those born at 37 to 38 completed weeks it was 1.1.
The association of gestational age with all-cause mortality was found both in women and men. The findings were essentially similar across four Nordic countries.
“It’s important to remember that overall adult mortality before age 50 is (very) low and even such an increased risk remains low in absolute numbers,” says professor Eero Kajantie.
Yet, the finding illustrates preterm birth as a new risk factor for mortality from these disorders in adult life, and highlights that prevention of chronic diseases, for example through healthy lifestyle, may be particularly beneficial for children and adults born preterm.
Dr. Kari Risnes, lead author of the study from NTNU Norway, says: "This study shows the potentials offered by combining the national registers in the Nordic countries. Not only were we able to design the largest study to date, but also the most detailed, using individual level data. This enabled us to assess specific chronic diseases, the role of family factors and provide sex-specific results."
“We have several ongoing Nordic register studies, in which we assess the health, the prevalence of specific diseases and transition to adulthood among children and adults born preterm. We are eagerly waiting for their results,” Eero Kajantie continues.
The study received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 733280 “Research on Children and Adults Born Preterm” (RECAP) and is part of the RECAP substudy NORDCAP “Nordic Children and Adults Born Preterm”. Other funders of the NORDCAP project are the Academy of Finland and many Finnish and Nordic foundations.
Source
Risnes K, Bilsteen JF, Brown P, et al. Mortality Among Young Adults Born Preterm and Early Term in 4 Nordic Nations. JAMA Netw Open. 2021;4(1):e2032779. doi:10.1001/jamanetworkopen.2020.32779https://recap-preterm.eu/
More information
Eero Kajantie
Research manager, professor
THL
Tel. +358 29 524 8610
[email protected]
Nordic Children and Adults Born Preterm (NORDCAP)
RECAP Research on Children and Adults Born Preterm
Previous information on the topic
Children born preterm are more likely to be placed outside the home. THL press release 27 Dec 2019.
