Association between birth weight and risk of cardiovascular disease: Evidence from UK Biobank

Birth weight has been linked to cardiovascular disease (CVD) risk in adulthood, but no consensus has emerged on the threshold of birth weight for the lowest CVD risk and few studies have examined potential interaction between birth weight and adult adiposity.

A total of 256,787 participants, who had birth weight data and were free of CVD at baseline, were included from UK Biobank. Multivariate restricted cubic splines and Cox regression models were used to assess the association between birth weight and CVD. We observed nonlinear inverse associations of birth weight with the risk of coronary heart disease (CHD), stroke, and heart failure. Participants with the first quintile of birth weight (≤2.85 kg) had higher risks for CHD (hazard ratio [HR] = 1.23, 95% confidence interval [CI]: 1.15-1.32), stroke (HR = 1.19, 95% CI: 1.03-1.37), and heart failure (HR = 1.28, 95% CI: 1.11-1.48), as compared to the fourth quintile (3.41-3.79 kg). There was a significant interaction between birth weight and adult body mass index (BMI) on CHD and heart failure (both P for interaction <0.001), showing the highest risk for those who had birth weight ≤2.85 kg and BMI ≥30 kg/m² (HR = 1.96, 95% CI: 1.70-2.25 and HR = 2.39, 95% CI: 1.77-3.22, respectively).

Our findings indicate nonlinear inverse associations between birth weight and CVD risk, with a threshold of 3.41-3.79 kg for the lowest risk. Moreover, low birth weight may interact with adult obesity to increase the risk of CHD and heart failure.