Preterm Birth and the Metabolic Syndrome in Adult Life: A Systematic Review and Meta-analysis
ABSTRACT BACKGROUND:Preterm birth is associated with features of the metabolic syndrome in later life. We performed a systematic review and meta-analysis of studies reporting markers of the metabolic syndrome in adults born preterm.METHODS:Reports of metabolic syndrome-associated features in adults (≥18 years of age) born at <37-week gestational age and at term (37- to 42-week gestational age) were included. Outcomes assessed were BMI, waist-hip ratio, percentage fat mass, systolic (SBP) and diastolic (DBP) blood pressure, 24-hour ambulatory SBP and DBP, flow-mediated dilatation, intima-media thickness, and fasting glucose, insulin, and lipid profiles.RESULTS:Twenty-seven studies, comprising a combined total of 17 030 preterm and 295 261 term-born adults, were included. In adults, preterm birth was associated with significantly higher SBP (mean difference, 4.2 mm Hg; 95% confidence interval [CI], 2.8 to 5.7; P < .001), DBP (mean difference, 2.6 mm Hg; 95% CI, 1.2 to 4.0; P < .001), 24-hour ambulatory SBP (mean difference, 3.1 mm Hg; 95% CI, 0.3 to 6.0; P = .03), and low-density lipoprotein (mean difference, 0.14 mmol/L; 95% CI, 0.05 to 0.21; P = .01). The preterm-term differences for women was greater than the preterm-term difference in men by 2.9 mm Hg for SBP (95% CI [1.1 to 4.6], P = .004) and 1.6 mm Hg for DBP (95% CI [0.3 to 2.9], P = .02).CONCLUSIONS:For the majority of outcome measures associated with the metabolic syndrome, we found no difference between preterm and term-born adults. Increased plasma low-density lipoprotein in young adults born preterm may represent a greater risk for atherosclerosis and cardiovascular disease in later life. Preterm birth is associated with higher blood pressure in adult life, with women appearing to be at greater risk than men.
SourceAvailable from: Marika Sipola-Leppänen[Show abstract] [Hide abstract]
ABSTRACT: Adults born preterm have higher blood pressure (BP) than those born at term. Most studies have focused on preterm birth, and few have assessed BP variability, an independent risk factor of cardiovascular disease. We studied the association of preterm birth with 24-hour ambulatory BP, measured by an oscillometric device, in 42 young adults born early preterm (<34 weeks), 72 born late preterm (34-36 weeks), and 103 controls (≥37 weeks). Sleep was confirmed with accelerometry in 72.4% of subjects. The 24-hour systolic BP of adults born early preterm was 5.5 mm Hg higher (95% confidence interval, 1.9-9.3), awake systolic BP was 6.4 mm Hg higher (95% confidence interval, 2.8-10.1), and sleeping systolic BP was 2.9 mm Hg higher (95% confidence interval 0.3-7.5) when adjusted for age, sex, and use of accelerometry. The differences remained similar when adjusted for height, body mass index, physical activity, smoking, parental education, maternal body mass index, smoking during pregnancy, and gestational diabetes mellitus and attenuated slightly when adjusted for maternal hypertensive pregnancy disorders. Adults born early preterm also had higher BP variability as indicated by higher individual standard deviations of systolic BP and diastolic BP. Although our results were consistent with a dose-response relationship between shorter gestation and higher BP, the difference between the late preterm and term groups was not statistically significant. Our results suggest that the higher BP in adults born early preterm is present during both waking and sleeping hours, may be more pronounced during waking hours, and is accompanied by higher individual BP variability. © 2015 American Heart Association, Inc.Hypertension 01/2015; 65(3). DOI:10.1161/HYPERTENSIONAHA.114.04717 · 7.63 Impact Factor
06/2013; 5(1):1-77. DOI:10.4199/C00084ED1V01Y201305ISP038
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ABSTRACT: What is the magnitude of the association between a woman's gestational age at her own birth and her fecundability (cycle-specific probability of conception)? We found a 62% decrease in fecundability among women born <34 weeks of gestation relative to women born at 37-41 weeks of gestation, whereas there were few differences in fecundability among women born at later gestational ages. One study, using retrospectively collected data on time-to-pregnancy (TTP), and self-reported data on gestational age, found a prolonged TTP among women born <37 gestational weeks (preterm) and with a birthweight ≤1500 g. Other studies of women's gestational age at birth and subsequent fertility, based on data from national birth registries, have reported a reduced probability of giving birth among women born <32 weeks of gestation. We used data from a prospective cohort study of Danish pregnancy planners ('Snart-Gravid'), enrolled during 2007-2011 and followed until 2012. In all, 2814 women were enrolled in our study, of which 2569 had complete follow-up. Women eligible to participate were 18-40 years old at study entry, in a relationship with a male partner, and attempting to conceive. Participants completed a baseline questionnaire and up to six follow-up questionnaires until the report of pregnancy, discontinuation of pregnancy attempts, beginning of fertility treatment, loss to follow-up or end of study observation after 12 months. Among women born <34 gestational weeks, the cumulative probability of conception was 12, 28 and 48% within 3, 6 and 12 cycles, respectively. Among women born at 37-41 weeks of gestation, cumulative probability of conception was 47, 67 and 84% within 3, 6 and 12 cycles, respectively. Relative to women born at 37-41 weeks' gestation, women born <34 weeks had decreased fecundability (fecundability ratio (FR) 0.38, 95% confidence interval (CI): 0.17-0.82). Our data did not suggest reduced fecundability among women born at 34-36 weeks of gestation or at ≥42 weeks of gestation (FR 1.03, 95% CI: 0.80-1.34, and FR 1.13, 95% CI: 0.96-1.33, respectively). Data on gestational age, obtained from the Danish Medical Birth Registry, were more likely to be based on date of last menstrual period than early ultrasound examination, possibly leading to an overestimation of gestational age at birth. Such overestimation, however, would not explain the decrease in fecundability observed among women born <34 gestational weeks. Another limitation is that the proportion of women born before 34 weeks of gestation was low in our study population, which reduced the precision of the estimates. By using prospective data on TTP, our study elaborates on previous reports of impaired fertility among women born preterm, suggesting that women born <34 weeks of gestation have reduced fecundability. The study was supported by the National Institute of Child Health and Human Development (R21-050264), the Danish Medical Research Council (271-07-0338), and the Health Research Fund of Central Denmark Region (1-01-72-84-10). The authors have no competing interests to declare. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: email@example.com.