The adverse cardiovascular (CV) effects of low birth weight that have been described in preterm/small-for-gestational-age (SGA) cohorts have been shown to possibly extend significantly into the general population, with lower birth weight associated with a greater risk for incident myocardial infarction (MI) and unhealthy left ventricular (LV) phenotypes, according to the results of a study that was conducted using data from the UK Biobank. Results of the analysis were published in the journal Heart.
The researchers sought to explore the associations between birth weight and clinical and imaging indicators of CV health and to assess mechanistic pathways in the UK Biobank. They used competing risk regression to estimate the relationship among birth weight and incident MI and mortality (all-cause, CV disease, ischemic heart disease, MI) over 7 to 12 years of longitudinal follow-up, with adjustments made for sex, age, deprivation, maternal smoking/hypertension, and maternal/paternal diabetes.
They utilized mediation analysis to assess the role played by childhood growth, adulthood obesity, cardiometabolic diseases, and blood biomarkers in mediation of the relationship between birth weight and MI. They used linear regression to estimate the associations of birth weight with LV stroke volume, LV mass-to-volume ratio, LV global function index, global longitudinal strain, and left atrial ejection fraction.
The association of birth weight with disease-specific mortality outcomes and incident acute MI was evaluated in a total of 258,787 participants of White ethnicities from the UK Biobank. Overall, 61% of the participants were women. The median participant age was 56 years (range, 49-62 years).
Results of the study showed that birth weight had a nonlinear relationship with incident MI, with a significant inverse below an optimal threshold of 3.2 kg (P =.60×10–5) and attenuation to the null above this threshold. The birth weight-MI effect was mediated through the following: hypertension (8.4%), glycated hemoglobin (7.0%), C-reactive protein (6.4%), high-density lipoprotein (5.2%), and high cholesterol (4.1%). Following Bonferroni correction, birth weight-mortality associations were statistically nonsignificant.
Further, among a total of 19,314 participants who received CV MRI, lower birth weight was associated with adverse LV remodeling.
Several limitations of the study include the birth weight variable being based on self-report, which may make it prone to recall bias. Other covariates are ascertained from self-reports as well. Misclassification in terms of these variables may be nondifferential, with individuals with a higher level of education and health status more prone to accurately recall their birth weight and parental medical history.
The authors wrote, “Further research is required to determine whether inclusion of birth weight may improve risk stratification and if preventative strategies targeted at individuals with lower birth weight have a role in improving clinical outcomes.”
Disclosure: One of the study authors has declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of the author’s disclosures.
Raisi-Estabragh Z, Cooper J, Bethell MS, et al. Lower birth weight is linked to poorer cardiovascular health in middle-aged population-based adults. Heart. Published online November 16, 2022. doi:10.1136/heartjnl-2022-321733