Preterm birth and cardiovascular risk factors in young adulthood.

Adults born preterm (birth before 37 weeks of gestation) have several increased risk factors of cardiovascular disease, including higher blood pressure compared with peers born at term. Although more than 80% of preterm births are late preterm (34 to 36 completed weeks of gestation), it is not clear to what extent the elevated risks are present in individuals with a history of late preterm birth. The mechanisms by which preterm birth is associated with elevated risks of cardiovascular disease, such as higher blood pressure, are unclear.

The aim of this study was to investigate the association of between preterm birth, throughout its gestational age range, with blood pressure and cardiac autonomic regulation in young adulthood in three cohort studies: the ESTER Preterm Birth study, the Helsinki Study of Very Low Birth Weight Adults and the McMaster Cohort. Adults born preterm had higher office-measured blood pressure, higher 24-hour ambulatory blood pressure, higher blood pressure variability, lower cardiac parasympathetic- and higher sympathetic autonomic regulation and slower heart rate recovery after exercise than their peers born at term. The higher blood pressure, increased blood-pressure variability, changes in cardiac autonomic regulation and slower post-exercise heart rate recovery seemed to be partially associated with unfavorable body composition, reduced physical activity and female sex.

Those with a history of preterm birth have higher levels of risk factors of cardiovascular disease than their peers born at term. As most of the risk factors, such as body composition and physical activity are modifiable, adults born preterm may especially benefit from promotion of healthy lifestyles and primary prevention.