Background and Aims Preterm birth is associated with raised blood pressure (BP) and other features of the metabolic syndrome in later life, but effect sizes and biological mechanisms are unknown. We conducted a meta-analysis to address these associations in adult life.
Methods We performed a systematic review and meta-analysis of studies in which metabolic syndrome associated indices were compared in adults (≥18 years of age) born preterm (< 37 weeks gestation) and at term (37–42 weeks gestation). Outcome measures included; systolic blood pressure (SBP), diastolic blood pressure (DBP), BMI, percentage fat mass and fasting plasma levels of lipids, glucose and insulin.
Results Data from 27 studies and 306,123 adults (16,094 preterm, 290,029 term) were included, with an average outcome age of 26.1 years. In adults, preterm compared with full-term birth was associated with significantly higher SBP (mean difference [95% confidence interval]: 4.2mmHg [2.7, 5.7], p<0.001), DBP (2.7mmHg [1.2, 4.2], p<0.001) and low density lipoprotein (LDL) (0.14mmol/L [0.05, 0.22], p=0.01). Meta-regression revealed a significant gender effect, with 3.0mmHg greater SBP in preterm compared to term women than in preterm-term men (95%CI: 1.3, 4.7, p=0.002); for DBP this difference was 2.1mmHg greater (0.6, 3.6, p=0.009).
Conclusions Preterm compared to term birth, is associated with higher blood pressure and LDL in adult life. Women born preterm appear to be at greater risk than men born preterm. Follow-up of older subjects born preterm will be required to determine if the effects we observe are exacerbated by age.