Vitamin D and parathormone levels of late-preterm formula fed infants during the first year of life

Vasileios Giapros (1) , Vasiliki Schiza (1) , Anna Challa (1) , Vasileios Cholevas (1) , Paraskevi Theocharis (1) , Georgios Kolios (1) , Constantina Pantou (1) , Styliani Andronikou (1)

1 Neonatology

Objective: Preterm infants are at risk for low vitamin D but documentation on late-preterm infants is sparse. This prospective study monitored longitudinally vitamin D and parathormone (PTH) levels in late-preterm, formula fed infants during the first year of life, taking into consideration in-utero and postnatal growth, season and diet. Population and methods: The study population comprised 128 infants of gestational age (GA) 32-36 weeks; 102 were appropriate (AGA) and 26 small for GA (SGA). Serum levels of vitamin D [25(OH)D], PTH calcium (Ca), phosphate (P) and alkaline phosphate (ALP) were estimated at 2 and 6 weeks and at 3,6,9 and 12 months of age. Results: The 25(OH)D levels were relatively low at 2 and 6 weeks in both AGA and SGA infants (21±11, 20±7 ng/ml and 25±16, 23±8 ng/ml respectively), but increased at 6 months (45±14, 47±10ng/ml) and remained stable thereafter. SGA infants had lower 25(OH)D levels at 9 and 12 months (AGA 45±14, 47±18ng/ml vs SGA 38±13, 37±13 ng/ml, p<0.05). 25(OH)D deficiency (<20ng/ml) was found in 18.5% of measurements in 92 (72%) infants and 25(OH)D insufficiency (20-32ng/ml) in 29.2% of measurements in 99 (77.3%) infants. Most measurements with vitamin D <32ng/ml were observed at the first 3 study points, where PTH showed an inverse association with 25(OH)D, reaching a plateau thereafter. Conclusion: Late-preterm, formula fed infants may have suboptimal vitamin D levels and elevated PTH, especially during the first 3 months. Those born SGA may have lower vitamin D levels up to the end of the first year of life.

Mots clés: vitamin D; parathormone; late-preterm infant; small-for-gestational age

Domaines: Alimentation et Nutrition

Vasileios Giapros, Vasiliki Schiza, Anna Challa, Vasileios Cholevas, Paraskevi Theocharis, et al.. Vitamin D and parathormone levels of late-preterm formula fed infants during the first year of life. European Journal of Clinical Nutrition, 2011, ⟨10.1038/ejcn.2011.158⟩. ⟨hal-00676999⟩