The impact of congenital heart disease on somatic growth: a monozygotic twin study

Children with congenital heart disease (CHD) often experience growth faltering. However, somatic growth is significantly influenced by genetic and environmental factors. Given the unique genetic and environmental similarities of monozygotic twins, this study aims to evaluate the relationship between CHD and growth faltering, while minimizing the influence of these factors. We retrospectively reviewed data from 41 pairs of twins, where one had CHD and the other did not. Anthropometric measures were collected from birth to 3 years of age. Growth differences within the CHD group were further analyzed based on disease characteristics, including cyanosis, pulmonary artery hypertension (PAH), heart failure (HF), and ventricular physiology. Mixed-effects regression models assessed longitudinal differences between twins, and multiple linear regression analyses identified predictors of anthropometric z-scores at 1 year. The CHD group showed a significant decline in all growth parameters from 1 year of age (p < .001), with no significant improvement during the observation period. Growth faltering was more common in the CHD group (46.3%) compared to the non-CHD group (7.5%). Within the CHD group, children with HF had significantly lower weight for age z-score and height for age z-score (p < .05). Being small for gestational age (SGA) independently predicted lower weight and head circumference at 1 year.Conclusion: Children with CHD are at an elevated risk of growth faltering. HF and SGA appear to contribute to growth faltering, highlighting the importance of early recognition and targeted interventions. What is Known Children with congenital heart disease (CHD) are at increased risk for growth faltering, but the independent effect of CHD is not well established. What is New This twin study aims to control genetic and environmental factors, showing that CHD is associated with lower growth and an increased risk of growth faltering. Among affected twins, growth outcomes also vary by disease and clinical characteristics.