Petit poids de naissance: dernières publications ...

Blood pressure in the small-for-gestational age newborn.

Strambi M, Vezzosi P, Buoni S, Berni S, Longini M.

Minerva Pediatr. 2004; 56:603-10.

AIM: The aim of the paper is to verify the existence of an inversecorrelation between birth weight and blood pressure (BP) in neonates,infants and adolescents. METHODS: BP was measured at 7 days, 3, 6, 9, 12months and 7-18 years in 432 subjects born at term at the Department ofPediatrics, Obstetrics and Reproductive Medicine, University of Siena;228 of these subjects were small for gestational age (SGA) and 204appropriate for gestational age (AGA). For small babies, BP was measuredwith a DYNAMAP oscillometer which provides digital visualisation ofsystolic, diastolic and mean arterial pressure and heart rate. In olderchildren, a mercury sphygmomanometer was used. Statistical analysis wascarried out with SPSS 8.01 software using the Kolmogorov-Smirnov testfor normality of populations. RESULTS: Statistical analysis did notreveal any significant differences between SGA and AGA subjects in thevarious age classes of the first 12 months of life. Significantcorrelation was found between 7 and 18 years with differences in thevarious age classes for systolic pressure. Subjects with normalbirthweight had lower systolic and diastolic BP. SGA males had higherrisk of high systolic and diastolic pressure, whereas SGA females wereonly at higher risk for elevated diastolic pressure. CONCLUSIONS: SGAsubjects should be monitored for BP and life-style between 7 and 18years to risk of cardiovascular disease.

Aortic wall thickness in newborns with intrauterine growth restriction.Skilton MR, Evans N, Griffiths KA, Harmer JA, Celermajer DS.

Lancet. 2005;365:1484-6

Much epidemiological evidence has linked low birthweight with late cardiovascular risk. We measured aortic wall thickness (a marker of early atherosclerosis) by ultrasonography in 25 newborn babies with intrauterine growth restriction and 25 with normal birthweight. Maximum aortic thicknesses were significantly higher in the babies with intrauterine growth restriction (810 microm [SD 113]) than in those without (743 microm [76], p=0.02), more so after adjustment for birthweight (300 microm/kg [45] vs 199 microm/kg [29], p<0.0001).>

Long-term renal follow-up of extremely low birth weight infants.

Rodriguez-Soriano J, Aguirre M, Oliveros R, Vallo A.

Pediatr Nephrol. 2005 May;20(5):579-84

There is evidence that low birth weight caused by intrauterine growth retardation adversely affects normal renal development. Very little information on this issue is available on children born very prematurely. This investigation examined clinical and functional renal parameters in 40 children (23 boys, 17 girls) ranging in age between 6.1 and 12.4 years and weighing less than 1000 g at birth. Results were compared to those obtained in 43 healthy children of similar age and gender. Study subjects were significantly smaller and thinner than control subjects (mean height SDS: -0.36 vs. +0.70; and mean BMI SDS: -0.56 vs. +1.18). Systolic, diastolic, and mean blood pressures did not differ from those of controls. Renal sonography revealed no abnormality, and mean percentiles for renal length and volume appeared normal. In comparison with controls, plasma creatinine concentration (0.62+/-0.1 vs. 0.53+/-0.1 mg/dl) and estimated creatinine clearance (117+/-17 vs. 131+/-17 ml min(-1) 1.73 m(-2)) differed significantly. No significant differences were observed in microalbuminuria values, but five study subjects (12.5%) presented values above the upper limit of normality. A defect in tubular phosphate transport was also evident: TmP/GFR (3.6+/-0.4 vs. 4.2+/-0.8 mg/dl) and TRP (83+/-5% vs. 90+/-4%) were significantly lower, and urinary P excretion, estimated by the ratio UP/UCr, was significantly higher (1.2+/-0.4 vs. 0.9+/-0.4 mg/mg) than controls. Urinary calcium excretion, estimated by the UCa/UCr ratio, was also significantly higher (0.15+/-0.07 vs. 0.12+/-0.09 mg/mg). These data clearly demonstrate that both GFR and tubular phosphate transport are significantly diminished in school-age children born with extreme prematurity, probably as a consequence of impaired postnatal nephrogenesis.

Commentaires: Trois publications récentes qui s'ajoutent à la littérature déjà prolixe depuis les premières publications de Barker à propos des conséquences sur la pression artérielle (PA) et la fonction rénale du retard de croissance intra-utérin.

L'étude italienne confirme ce qui a déjà été largement démontré à savoir que chez les enfants nés avec un petit poids de naissance (PPN) la PA est plus élevée à l'adolescence ou à l'âge adulte.

L'étude australienne publiée dans Lancet montre que l'épaisseur de l'intima aortique est plus importante chez les nouveaux-nés avec PPN. Ce marqueur précoce de la maladie athéromateuse est donc visible dès la naissance !

Enfin l'étude espagnole nous montre à partir du suivi de 40 enfants nés avec PN ... (suite ci-dessous)

RS