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Cited by 33Birth, Development, and HealthInfant Development and Preterm CareChronic Disease Management Strategies

Preterm birth and the risk of chronic disease multimorbidity in adolescence and early adulthood: A population-based cohort study

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Heikkilä, Katriina, Pulakka, Anna, Metsälä, Johanna, Alenius, Suvi, Hovi, Petteri, Gissler, Mika, Sandin, Sven, Kajantie, Eero·2021·PLOS ONE
DOI 10.1371/journal.pone.0261952PMC PMC8719774
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Abstract

Background: People who were born prematurely have high risks of many individual diseases and conditions in the early part of the life course. However, our knowledge of the burden of multiple diseases (multimorbidity) among prematurely born individuals is limited. We aimed to investigate the risk and patterns of chronic disease multimorbidity in adolescence and early adulthood among individuals born across the spectrum of gestational ages, comparing preterm and full-term born individuals. Methods and findings: We used individual-level data from linked nationwide registers to examine the associations of gestational age at birth with specialised healthcare records of ≥2 chronic diseases (multimorbidity) in adolescence (age 10–17 years) and early adulthood (age 18–30 years). Our study population comprised 951,116 individuals (50.2% females) born alive in Finland between 1 st January 1987 and 31 st December 2006, inclusive. All individuals were followed from age 10 years to the onset of multimorbidity, emigration, death, or 31 December 2016 (up to age 30 years). We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for multimorbidity using flexible parametric survival models. During 6,417,903 person-years at risk (median follow-up: 7.9 years), 11,919 individuals (1.3%) had multimorbidity in adolescence (18.6 per 10,000 person-years). During 3,967,419 person-years at risk (median follow-up: 6.2 years), 15,664 individuals (1.7%) had multimorbidity in early adulthood (39.5 per 10,000 person-years). Adjusted HRs for adolescent multimorbidity, comparing preterm to full-term born individuals, were 1.29 (95% CI: 1.22 to 1.36) and 1.26 (95% CI: 1.18 to 1.35) in females and males, respectively. The associations of preterm birth with early adult multimorbidity were less marked, with the adjusted HRs indicating 1.18-fold risk in females (95% CI: 1.12 to 1.24) and 1.10-fold risk in males (95% CI: 1.04 to 1.17). We observed a consistent dose-response relationship between earlier gestational age at birth and increasing risks of both multimorbidity outcomes. Compared to full-term born males, those born at 37–38 weeks (early term) had a 1.06-fold risk of multimorbidity in adolescence (95% CI: 0.98 to 1.14) and this risk increased in a graded manner up to 6.85-fold (95% CI: 5.39 to 8.71) in those born at 23–27 weeks (extremely premature), independently of covariates. Among females, the same risks ranged from 1.16-fold (95% CI: 1.09 to 1.23) among those born at 37–38 weeks to 5.65-fold (95% CI: 4.45 to 7.18) among those born at 23–27 weeks. The corresponding risks of early adult multimorbidity were similar in direction but less marked in magnitude, with little difference in risks between males and females born at 36–37 weeks but up to 3-fold risks observed among those born at 23–27 weeks. Conclusions: Our findings indicate that an earlier gestational age at birth is associated with increased risks of chronic disease multimorbidity in the early part of the life course. There are currently no clinical guidelines for follow-up of prematurely born individuals beyond childhood, but these observations suggest that information on gestational age would be a useful characteristic to include in a medical history when assessing the risk of multiple chronic diseases in adolescent and young adult patients.

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Cited by

Sorted by citations

Authors
Heikkilä, K., Pulakka, A., Metsälä, J., Alenius, S., Hovi, P., Gissler, M., Sandin, S., & Kajantie, E.
Affiliations
  • Finnish Institute for Health and Welfare (FI)
  • University of Helsinki (FI)
  • Region Stockholm (SE)
  • Karolinska Institutet (SE)
  • Norwegian University of Science and Technology (NO)
Corresponding author
Heikkilä, Katriina
ORCID
Venue
PLOS ONE
Publisher
Public Library of Science (PLoS)
Published
2021-12-31
Volume
16
Issue
12
Pages
e0261952
ISSN
1932-6203 (ISSN-L)
DOI
10.1371/journal.pone.0261952
PMC
PMC8719774
OpenAlex
W4206393763
Cited by
33
References
2
Citations by year
2026: 6 · 2025: 8 · 2024: 4 · 2023: 13 · 2022: 2
FWCI
4.69
Type
journal article
Language
en
Open access
Licence
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Työväentutkimus Vuosikirja (submittedVersion)
  • NORA - Norwegian Open Research Archives (submittedVersion, cc-by)
  • STM:n Hallinnonalan avoin julkaisuarkisto (Julkari) (submittedVersion)
Funders
  • Academy of Finland
  • Sigrid Juséliuksen Säätiö
  • Horizon 2020
  • Lastentautien Tutkimussäätiö
Topics
  • Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Birth, Development, and Health
  • Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Infant Development and Preterm Care
  • Health Sciences › Medicine › Epidemiology › Chronic Disease Management Strategies
Keywords
preterm birth, gestational age, multimorbidity, chronic disease, adolescence, early adulthood, term birth, sex differences, life course, Finland, medical records, birth cohort
MeSH terms
Multimorbidity, Adolescent, Adult, Child, Chronic Disease, Female, Finland, Gestational Age, Humans, Infant, Newborn, Male, Registries, Risk Factors, Cohort Studies, Premature Birth, Young Adult

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