Health profile of young adults born preterm: negative effects of rapid weight gain in early life.

INTRODUCTION: Early postnatal weight gain is associated with determinants of cardiovascular disease (CVD) and type 2 diabetes mellitus (DM2) in adults born term. We aimed to investigate the association of weight gain during different periods, and weight trajectories in early life after preterm birth, with determinants of CVD and DM2 in early adulthood. METHODS: Associations of first-year growth and tempo of weight gain with determinants of CVD and DM2 in 162 young adults (18-24 yr) born preterm (gestational age <36 wk) were determined and compared with data of young adults born term (n = 217). RESULTS: Gain in weight for length in the period from preterm birth up to term age, and in the first 3 months after term age, was positively associated with body fat percentage and waist circumference at 21 yr. Gain in weight for length in the first 3 months after term age was also positively associated with total cholesterol and low-density lipoprotein cholesterol levels in early adulthood. Subjects with the highest gain in weight from birth to term age (highest quartile) had significantly higher body fat percentage, waist circumference, acute insulin response, and disposition index in early adulthood than the subgroups with moderate and low gain in weight. Rapid catch-up in weight during the first 3 months after term age resulted in a higher fat percentage, waist circumference, and serum triglycerides level than slower catch-up in weight. CONCLUSION: Accelerated neonatal gain in weight relative to length after preterm birth (immediately after birth and during the first 3 months after term age) is associated with determinants of CVD in early adulthood and should therefore be avoided.

Does preterm birth influence cardiovascular risk in early adulthood?

OBJECTIVE: To investigate the effect of preterm birth on risk factors for cardiovascular disease (CVD), independent of birth size. STUDY DESIGN: Observational study using data of 406 healthy participants aged 18-24 years, from the PROgramming factors for Growth And Metabolism and Prematurity and Small for Gestational Age studies. Associations between gestational age (GA), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), blood pressure variability, heart rate (HR), pulse wave velocity, and carotid intima media thickness (cIMT) were studied. To study the differential effects of preterm birth and small birth size for gestational age, these parameters were also analyzed in subgroups born either preterm or term: young adults born small for gestational age with short or normal adult stature, and young adults born appropriate for gestational age with normal adult stature. RESULTS: Subjects born preterm (GA <36 weeks) had higher unadjusted SBP, PP, SBP and DBP variability, and HR, but a lower DBP than subjects born term. GA was inversely associated with SBP, PP, blood pressure variability, and HR, and positively associated with DBP, also after adjustment for confounders. There was no effect of GA on pulse wave velocity and cIMT, a marker of atherosclerosis. Of all the CVD risk factors measured, higher PP affected cIMT the most. CONCLUSIONS: Young adults born preterm might have a higher risk for CVD than those born term.

Methylphenidate and the response to growth hormone treatment in short children born small for gestational age.

BACKGROUND: Growth hormone (GH) treatment has become a frequently applied growth promoting therapy in short children born small for gestational age (SGA). Children born SGA have a higher risk of developing attention deficit hyperactivity disorder (ADHD). Treatment of ADHD with methylphenidate (MP) has greatly increased in recent years, therefore more children are being treated with GH and MP simultaneously. Some studies have found an association between MP treatment and growth deceleration, but data are contradictory. OBJECTIVE: To explore the effects of MP treatment on growth in GH-treated short SGA children METHODS: Anthropometric measurements were performed in 78 GH-treated short SGA children (mean age 10.6 yr), 39 of whom were also treated with MP (SGA-GH/MP). The SGA-GH/MP group was compared to 39 SGA-GH treated subjects. They were matched for sex, age and height at start of GH, height SDS at start of MP treatment and target height SDS. Serum insulin-like growth factor-I (IGF-I) and IGF binding protein-3 (IGFBP-3) levels were yearly determined. Growth, serum IGF-I and IGFBP-3 levels during the first three years of treatment were analyzed using repeated measures regression analysis. RESULTS: The SGA-GH/MP group had a lower height gain during the first 3 years than the SGA-GH subjects, only significant between 6 and 12 months of MP treatment. After 3 years of MP treatment, the height gain was 0.2 SDS (± 0.1 SD) lower in the SGA-GH/MP group (P = 0.17). Adult height was not significantly different between the SGA-GH/MP and SGA-GH group (-1.9 SDS and -1.9 SDS respectively, P = 0.46). Moreover, during the first 3 years of MP treatment IGF-I and IGFBP-3 measurements were similar in both groups. CONCLUSION: MP has some negative effect on growth during the first years in short SGA children treated with GH, but adult height is not affected.

Preterm birth does not affect bone mineral density in young adults.

OBJECTIVE: Previous studies showed conflicting data on the effect of prematurity on bone mineral density (BMD) in infants and children. Only a few studies investigated the long-term effects of prematurity on BMD in early adulthood. The objective of our study was to assess the long-term effects of preterm birth on BMD of the total body (BMD(TB)), lumbar spine (BMD(LS)) and bone mineral apparent density of the LS (BMAD(LS)). DESIGN: Cross-sectional study. METHODS: It consists of two hundred and seventy-six healthy subjects without serious postnatal complications, aged 18-24 years. The contribution of gestational age to the variance in BMD in young adulthood and the differences in BMD between 151 subjects born preterm (median gestational age 32.2 weeks (interquartile range (IQR) 30.3-34.0)) and 125 subjects born at term (median gestational age 40.0 weeks (IQR 39.0-40.0)) were investigated. BMD was determined by dual-energy X-ray absorptiometry. RESULTS: There were no significant linear correlations between gestational age and BMD(TB) (r=0.063, P=0.30), BMD(LS) (r=0.062, P=0.31) and BMAD(LS) (r=0.069, P=0.26). Also after adjustment for possible confounders, gestational age was no significant contributor to the variance in BMD(TB) (P=0.27), BMD(LS) (P=0.91) and BMAD(LS) (P=0.87). No significant differences were found between preterm and term subjects with regard to BMD(TB), BMD(LS) and BMAD(LS). CONCLUSION: In our cohort of 276 young adults, aged 18-24 years, gestational age was not a significant determinant in the variance of BMD. Preterm birth without serious postnatal complications is not associated with a lower BMD in young adulthood.