High prevalence of vitamin D deficiency in newborn infants of high-risk mothers

Objective

To determine the prevalence of vitamin D deficiency in newborn infants of mothers at risk of vitamin D deficiency because of dark skin or the wearing of concealing clothes (such as a veil) compared with a group presumed not to be at risk. A second aim was to correlate these newborn infants'' vitamin D concentrations with biochemical parameters of vitamin D metabolism and bone turnover at birth.

Design

A prospective study conducted between April 2004 and February 2006 including women delivering during this period and their newborn infants.

Setting

The outpatient clinic of the obstetrics department, Sint Franciscus Gasthuis, Rotterdam, the Netherlands.

Patients

Eighty seven newborn infants of healthy mothers with either dark skin and/or concealing clothing (risk group) or light skin (control group).

Results

We found a significant difference in the prevalence of vitamin D deficiency (25‐hydroxyvitamin D₃ <25 nmol/l) between newborn infants of mothers at risk and those of mothers in the control group (63.3% vs 15.8%; p<0.001). Mean alkaline phosphatase concentrations were significantly higher in the at risk group.

Conclusions

Newborn infants of mothers with dark skin or wearing concealing clothes are at great risk of vitamin D deficiency at birth. The clinical implications are unknown. Further research is necessary to determine the long‐term consequences of maternal and neonatal vitamin D deficiency so that guidelines on vitamin D supplementation during pregnancy can be issued.     

早产儿出生时维生素D水平及影响因素分析

目的分析早产儿出生时维生素D水平及其可能影响因素。方法采集600例早产儿出生24 h内静脉血,检测血清25-羟基维生素D[25(OH)D]水平,并分析早产儿性别、出生体重、出生季节、胎龄,以及母亲的年龄、职业、早孕期体重指数(BMI)、分娩方式及妊娠期并发症等对血清25(OH)D水平的影响。结果早产儿维生素D缺乏、不足、充足的比例分别为42.0%、38.7%和19.3%。夏、秋季出生的早产儿血清25(OH)D水平显著高于冬季(P0.05),维生素D缺乏的发生率显著低于春、冬季(P0.003)。与母亲年龄≥30岁者比较,年龄30岁母亲所生早产儿血清25(OH)D水平显著降低(P0.05),维生素D缺乏的发生率显著增高(P0.017)。与母亲肥胖者比较,超重或体重正常母亲所生早产儿血清25(OH)D水平显著增高(P0.05),维生素D缺乏的发生率显著降低(P0.006)。母亲妊娠合并子癎前期者,其早产儿血清25(OH)D水平显著低于无子癎前期者(P0.05),维生素D缺乏的发生率显著高于无子癎前期者(P0.017)。多因素分析结果显示,冬春季出生、母亲年龄30岁及早孕期BMI≥28 kg/m2为早产儿维生素D缺乏的危险因素(P0.05)。结论早产儿维生素D缺乏发生率较高,有维生素D缺乏高危因素的早产儿生后需尽早补充维生素D。     

High prevalence of moderately severe vitamin D deficiency in preterm infants

Background: The recommended dose of vitamin D supplementation of preterm infants is based on data from populations in which severe vitamin D deficiency is uncommon and may be inadequate for infants in high risk population. However, data on vitamin D status of preterm infants in high‐risk populations, such as Middle Eastern countries is scarce. Methods: This study investigates the vitamin D status of Arab mothers and their preterm infants. Maternal serum and cord blood 25(OH)D, calcium (Ca), phosphorus (P) and alkaline phosphate (ALP) were measured at delivery. Serum 25(OH)D was measured by HPLC while the other biochemical parameters were measured by standard autoanalyzer. Results: Thirty‐four preterm infants were studied. The mean gestational age was 31.4 weeks and birth weight was 1667 g. The median serum 25(OH)D of 17.0 nmol/L in 28 mothers and 14.5 nmol/L in 34 cord blood samples were low. The median maternal and cord blood Ca, P and ALP levels were within normal range. Fifteen (44%) of the infants had moderately severe vitamin D deficiency (serum 25 (OH)D levels <12.5 nmol/L). The median serum 25(OH)D levels of mothers who had reportedly taken prenatal vitamin D supplementation and those who had not were similar (17.3 vs 16.3) nmol/L. The mean serum 25(OH)D levels among preterm infants in this study were low when compared to levels in Caucasians preterm infants on which the current vitamin D recommendations are based. Conclusion: The high prevalence of moderately severe vitamin D deficiency in Arab preterm infants provides a justification to investigate vitamin D requirement of preterm infants in this and other high‐risk populations.     

早产儿维生素D两种补充方案的疗效对比：前瞻性随机对照研究

目的 探讨不同维生素D补充方案对出生胎龄 < 34周早产儿生后第28天维生素D营养状况的影响。方法 将59例2018年10月至2019年10月出生胎龄 < 34周的住院早产儿随机分为肌注组（n=30）和口服组（n=29）。肌注组单次肌内注射维生素D₃注射液（10 000 IU/kg）,口服组口服维生素D₃滴剂（900 IU/d）,持续25 d。采集两组患儿生后48 h内（维生素D₃补充前）及第28天静脉血,检测血清25-羟维生素D[25(OH) D]水平。结果 生后48 h内,59例早产儿维生素D缺乏（≤15 ng/mL）率为78%;两组血清25(OH) D水平及维生素D缺乏率比较差异无统计学意义（P > 0.05）。生后第28天,肌注组血清25(OH) D水平显著高于口服组（P < 0.05）,肌注组维生素D缺乏率显著低于口服组（P < 0.05）,且无维生素D过量或中毒病例。结论 单次肌内注射10 000 IU/kg维生素D₃可显著提升出生胎龄 < 34周早产儿生后第28天血清25(OH) D水平,且能安全并有效地降低维生素D缺乏率。     

Diet, clothing, sunshine exposure and micronutrient status of Arab infants and young children

Vitamin C and D levels in Arab women and their newborn infants have been shown to be low. We investigated the prevalence of and risk factors for possible hypovitaminosis C and D in a convenience sample of 51 hospitalized children without clinical features of vitamin C or D deficiency. The mean age was 15.4 months. The serum vitamin C concentration was low in the mothers but normal in the children. Both mothers and children had low serum 25-hydroxyvitamin D (25-OHD) concentrations. Fifty per cent of the mothers and 22% of the infants and children had hypovitaminosis D (serum 25-OHD level < 25 nmol/l). Infants who received dietary vitamin D supplementation had a higher mean (SD) serum 25-OHD concentration than the unsupplemented group (62.5 (29.8) vs 38.5 (27.3), p = 001). Cutaneous light exposure in these children was poor. The children's serum 25-OHD concentration correlated with dietary vitamin D supplementation and maternal serum 25-OHD levels. The results suggest normal vitamin C status but a possible high prevalence of hypovitaminosis D in Arab children and their mothers in UAE. Health education to encourage greater sunshine exposure and improvement in maternal vitamin D stores and the availability of adequate vitamin D supplements would improve children's vitamin D status. The study indicates that hypovitaminosis D continues to be an important maternal and child health problem, despite the abundant sunshine.     

早产儿维生素D两种补充方案的疗效对比：前瞻性随机对照研究

目的 探讨不同维生素D补充方案对出生胎龄 < 34周早产儿生后第28天维生素D营养状况的影响。方法 将59例2018年10月至2019年10月出生胎龄 < 34周的住院早产儿随机分为肌注组（n=30）和口服组（n=29）。肌注组单次肌内注射维生素D₃注射液（10 000 IU/kg）,口服组口服维生素D₃滴剂（900 IU/d）,持续25 d。采集两组患儿生后48 h内（维生素D₃补充前）及第28天静脉血,检测血清25-羟维生素D[25(OH) D]水平。结果 生后48 h内,59例早产儿维生素D缺乏（≤15 ng/mL）率为78%;两组血清25(OH) D水平及维生素D缺乏率比较差异无统计学意义（P > 0.05）。生后第28天,肌注组血清25(OH) D水平显著高于口服组（P < 0.05）,肌注组维生素D缺乏率显著低于口服组（P < 0.05）,且无维生素D过量或中毒病例。结论 单次肌内注射10 000 IU/kg维生素D₃可显著提升出生胎龄 < 34周早产儿生后第28天血清25(OH) D水平,且能安全并有效地降低维生素D缺乏率。     

Effect of combined maternal and infant vitamin D supplementation on vitamin D status of exclusively breastfed infants

Severe vitamin D deficiency in mothers and their breastfed infants is a significant health problem in the Middle East. Supplementation of the breastfed infant alone with the recommended dose of vitamin D may be insufficient in high‐risk population. We investigated the effect of combined maternal and infant vitamin D supplementation on vitamin D status of the breastfed infant. We examined also the effect of supplementation on vitamin D antirachitic activity of breast milk in a subset of mothers. Healthy breastfeeding mothers (n = 90) were randomly assigned to 2000 IU daily (group 1) or 60 000 IU monthly (group 2) of vitamin D₂, and all their infants (n = 92) received 400 IU daily of vitamin D₂ for 3 months. Most infants had vitamin D deficiency – 25‐hydroxyvitamin D [25(OH)D] ≤ 37.5 nmol L^?1– at study entry. Serum 25(OH)D concentrations at 3 months increased significantly from baseline in infants of mothers in group 1 (13.9 ± 8.6 vs. 49.6 ± 18.5 nmol L^?1, P < 0.0001) and group 2 (13.7 ± 12.1 vs. 44.6 ± 15.0 nmol L^?1, P < 0.0001). Maternal and infant serum 25(OH)D concentrations correlated positively at baseline (r = 0.36, P = 0.01) and 3 months (r = 0.46, P = 0.002). Milk antirachitic activity increased from undetectable (<20 IU L^?1) to a median of 50.9 IU L^?1. In conclusion, combined maternal and infant vitamin D supplementation was associated with a threefold increase in infants’ serum 25(OH)D concentrations and a 64% reduction in the prevalence of vitamin D deficiency without causing hypervitaminosis D.     

Vitamin D deficiency in a healthy group of mothers and newborn infants

Plasma 25-hydroxyvitamin D was measured in 40 healthy, mostly Black, mother-infant pairs. Although a majority of mothers received a daily prenatal multivitamin, vitamin D deficiency (<30 nmol/L), was found in 50% of mothers and 65% of their newborn infants, with a positive correlation between maternal and infant plasma 25-hydroxyvitamin D concentrations. Maternal vitamin D deficiency may represent an important risk factor for the development of rickets in children.     

Do breastfed infants need supplemental vitamins?

Table 2 shows that human milk will not meet the DRI for all vitamins in breastfeeding infants. The most glaring discrepancy between intake and the RDA is for vitamin D, although, as discussed, infants may synthesize this from sunlight exposure. Vitamin K must be given in the newborn period. Deficiencies of other vitamins are rare, especially if mothers are nourished adequately. If breastfeeding infants are to be supplemented with vitamin D or any other vitamins, the standard liquid preparations available all contain large amounts of the water-soluble and fat-soluble vitamins (except for vitamin K), which more than meets the RDA. The milk content of thiamin, pyridoxine, and niacin is correlated highly with maternal intake, and these vitamins are all present in relatively large amounts in standard multivitamin tablets given to lactating mothers. In conclusion, in healthy, breastfed infants of well-nourished mothers, there is little risk for vitamin deficiencies and the need for vitamin supplementation is rare. The exceptions to this are a need for vitamin K in the immediate newborn period and vitamin D in breastfed infants with dark skin or inadequate sunlight exposure.     

维生素D缺乏与早产儿坏死性小肠结肠炎的相关性

目的 评估维生素D水平对早产儿坏死性小肠结肠炎（NEC）的影响。方法 选取2016年1~12月于生后2 h内入新生儿科住院治疗的胎龄 < 36周的早产儿429例为研究对象,依据患儿是否发生NEC,将429例患儿分为NEC组（n=22）和非NEC组（n=407）。采集早产儿及其母亲入院时外周静脉血进行25-羟基维生素D（25-OHD）水平检测,比较两组早产儿和母亲血清25-OHD水平,Pearson相关分析早产儿和母亲血清25-OHD水平相关性,比较两组早产儿维生素D缺乏情况,单因素logistic回归分析早产儿NEC影响因素。结果 NEC组母亲和早产儿血清25-OHD水平均显著低于非NEC组（P < 0.001）。两组母亲和早产儿之间血清25-OHD水平均呈正向关（P < 0.001）。非NEC组与NEC组早产儿维生素D水平在正常、不足、缺乏、严重缺乏等状况的分布上比较差异有统计学意义（P < 0.001）。单因素logistic回归分析结果显示：胎龄、出生体重、母亲和早产儿25-OHD水平、机械通气持续时间、用氧持续时间和住院时间可能是NEC发生的影响因素（P < 0.05）。结论 母亲和早产儿低血清25-OHD水平与早产儿NEC的发生可能具有相关性,提示母孕期补充维生素D对于预防早产儿NEC的发生有重要意义。     

早产儿出生时25羟基维生素D水平与呼吸窘迫综合征关系分析

目的研究早产儿出生时血清25羟基维生素D[25(OH)D]水平与呼吸窘迫综合征(RDS)的关系。方法将2014年1月至2016年12月于新生儿病房住院的符合入组标准和排除标准的早产儿112例分为RDS组(n=72)和对照组(n=40)。收集两组患儿的一般临床资料,包括胎龄、出生体重、性别、分娩方式、1 min及5 min Apgar评分,以及母妊娠期糖尿病和产前激素使用情况。采集患儿的外周静脉血,分离血清,采用化学发光免疫分析法检测血清25(OH)D水平;采用二元logistic回归模型分析25(OH)D水平与RDS发生的关系。结果 RDS组1 min及5 min Apgar评分、血清25(OH)D水平显著低于对照组(P0.05),新生儿窒息及维生素D缺乏发生率显著高于对照组(P0.05)。经二元logistic回归分析结果显示,新生儿窒息(OR=2.633,95%CI:1.139~6.085)、维生素D缺乏(OR=4.064,95%CI:1.625~10.165)是导致早产儿RDS发生的危险因素(P0.05)。结论早产儿出生时维生素D缺乏可能与RDS发病风险增加有关,母孕期合理补充维生素D可能降低早产儿RDS发病率。     

Vitamin K deficiency in the newborn infant: prevalence and perinatal risk factors

The prevalence of vitamin K deficiency in newborn infants and the influence of perinatal risk factors were studied prospectively in 934 infants. A noncarboxylated prothrombin assay to detect proteins induced in vitamin K absence (PIVKA-II) was used to determine the presence of vitamin K deficiency; of 934 cord blood samples assayed, 2.9% were positive for PIVKA-II (0.015 to 0.15 U/ml). All infants found to have detectable PIVKA-II were born at term. The number of infants positive for PIVKA-II was greater in the group small for gestational age (7.4%) than in those appropriate (2.7%) or large (3.1%) for gestational age. Nine categories of perinatal risk groups were defined: however, the majority of infants who were PIVKA-II positive (63%) were normal. All infants received prophylactic vitamin K, and no infant with PIVKA-II in the cord sample subsequently had clinical bleeding. In two patients the rate of 50% disappearance of PIVKA-II after vitamin K administration approximated 70 hours. Two PIVKA-II positive patients with active bleeding or disseminated intravascular coagulation had an accelerated disappearance of 20 to 40 hours. The long disappearance time of PIVKA-II in a steady state may allow detection of vitamin K deficiency despite administration of vitamin K. The majority of cases of neonatal vitamin K deficiency occurred in normal newborn infants. Therefore, all infants should receive prophylactic vitamin K at birth.     

Maternal vitamin D deficiency and vitamin D supplementation in healthy infants

The objective of this study was to evaluate the common effects of maternal vitamin D deficiency, various doses of vitamin D given to newborns and the effects of these on vitamin D status in early childhood. Seventy-eight pregnant women and 65 infants who were followed up in various health centers were included in the sudy. 25-hydroxyvitamin-D (25-OHvitD), calcium (Ca), phosphorus (P) and alkaline phosphatase levels were measured in blood samples drawn from pregnant women in the last trimester. Infants born to these mothers were given 400 or 800 IU of vitamin D subsequently at the start of the second week. 25-OHvitD, Ca, P and alkaline phosphatase levels of the 65 infants who were brought in for controls (May-September 2000) were measured and hand-wrist X-rays were evaluated. We analyzed the relationship between vitamin D status of the mothers and infants and socio-economic status; mothers' dressing habits (covered vs uncovered), educational level, and number of pregnancies; and sunlight exposure of the house. Covered as a dressing habit meant covering the hair and sometimes part of the face and wearing dresses that completely cover the arms and legs. In 40 infants who were breast-fed and received the recommended doses of vitamin D on a regular basis, the relationship between serum vitamin D levels and supplementation doses given was analyzed. Serum 25-OHvitD level of the mothers was 17.50 +/- 10.30 and 94.8% of the mothers had a 25-OHvitD level below 40 nmol/L (below 25 nmol/L in 79.5%). The risk factors associated with low maternal 25-OHvitD were low educational level (p = 0.042), insufficient intake of vitamin D within diet (p = 0.020) and "covered" dressing habits (p = 0.012). 25-OHvitD level of the infants was 83.70 +/- 53.70 nmol/L, and 24.6% of the infants had 25-OHvitD levels lower than 40 nmol/L. Risk factors for low 25-OHvitD levels in infants were a) not receiving recommended doses of vitamin D regularly (p = 0.002) and b) insufficient sunlight exposure of the house (p = 0.033). There was a pour but significant correlation between maternal vitamin D levels and infants' 25-OHvitD levels at four months (r = 0.365, p < 0.05). No significant correlation was found between 25-OHvitD levels and supplementation doses of vitamin D (19 infants were supplemented with 400 IU/day and 21 with 800 IU/day of vitamin D) (p = 0.873). Severe maternal vitamin D deficiency remains a commonly seen problem in Turkey. However, vitamin D deficiency can be prevented by supplementation of vitamin D to newborns (at least 400 IU). Supplementation of 800 IU vitamin D in the areas of maternal vitamin D deficiency has no greater benefits for the infants.     

Heightened attention to supplementation is needed to improve the vitamin D status of breastfeeding mothers and infants when sunshine exposure is restricted

Although exclusively breastfed infants are at increased risk of vitamin D (vit D) deficiency if vit D supplementation is lacking and sun exposure is limited, assessment of both risk factors in the first year of life is lacking. We evaluated the contribution of vit D intake and sunlight exposure to vit D status in 120 healthy, breastfeeding mother–infant dyads, who were followed up for 1 year. Vitamin D intake and skin sunlight exposure were evaluated using questionnaires. Serum 25‐hydroxyvitamin D, parathyroid hormone (PTH) and alkaline phosphatase levels were determined post‐natally in mothers at 4 weeks and in infants at 4, 26 and 52 weeks. Vitamin D supplementation was low (<20%) and sunlight exposure was common (93%) in study infants. At 4 weeks, 17% of mothers were vit D deficient (<50 nmol L^?1) and 49% were insufficient (50–<75 nmol L^?1), while 18% of infants were severely vit D deficient (<25 nmol L^?1) and 77% were deficient (<50 nmol L^?1). At 26 weeks, winter/spring birth season and shorter duration of months of exclusive breastfeeding were protective of vit D deficiency in infants. Vitamin D deficiency in infants decreased to 12% at 52 weeks with sunlight exposure. Serum PTH levels were significantly higher in severely vit D deficient than sufficient infants. Vitamin D deficiency was widespread in early post‐partum breastfeeding mothers and infants, and declined to one in eight infants at 52 weeks due mostly to sunshine exposure. When sunlight exposure is limited or restricted, intensified vit D supplementation of breastfeeding mothers and infants is needed to improve vit D status.     

Vitamin D in infants with cystic fibrosis diagnosed by newborn screening

Aims:   Screening enables early nutritional deficiencies to be detected in those with cystic fibrosis (CF). Although vitamin deficiency is considered unlikely in older subjects with normal vitamin E levels, few studies have determined vitamin D status at diagnosis and its relationship to other fat-soluble vitamins.
Methods:   We reviewed vitamin levels in infants diagnosed with CF by newborn screening over a 5-year period in Melbourne, Australia. Vitamin D levels were determined using the IDS gamma-B 25-OH Vitamin D radio-immunoassay (Immunodiagnostic Systems Limited, Boldon, UK). Vitamins A and E were evaluated by high-performance liquid chromatography. We assessed the association between vitamin D level and sex, month of birth, pancreatic status, and vitamin A and E levels.
Results:   Fifty-eight infants were diagnosed at a median age of 1 month (range: 0–3 months). Initial vitamin D levels were assessed between 0.2 and 3.5 months in 30 (vitamin D) and 45 (vitamins A and E) infants. The number of infants deficient with vitamins D, E and A were 11 (37%), 7 (16%) and 27 (60%), respectively. Vitamin D levels were unrelated to sex, vitamin A or E levels, month of birth or pancreatic status, whereas vitamin A and E levels were significantly lower in those who were pancreatic insufficient. With supplementation, vitamin D increased over time.
Conclusions:   Vitamin D deficiency is common in infants newly diagnosed with CF by newborn screening and is unrelated to pancreatic status or predicted low vitamin E levels. Vitamin D deficiency is less common over time following treatment.     

Vitamin D status of White pregnant women and infants at birth and 4 months in North West England: A cohort study

The prevalence of vitamin D deficiency in pregnant white‐skinned women (WSW) and their infants has not been investigated at northern latitudes in a developed county. A 2‐year observational cohort study was undertaken in the North West of England to determine 25‐hydroxyvitamin D (25OHD) levels in WSW and their infants during pregnancy and 4 months postdelivery and to explore factors associated with these levels. Nutritional and lifestyle questionnaires were completed and 25OHD levels measured at 28 weeks and 4 months postdelivery. Twenty‐seven percent and 7% of WSW had insufficient and deficient levels of 25OHD during pregnancy and 48% and 11% four months postdelivery. WSW with Fitzpatrick skin‐type I (FST I) have significantly lower 25OHD than other skin types after controlling for time spent outside and vitamin D intake. Twenty‐four percent and 13% of infants had insufficient and deficient 25OHD levels at 4 months. Unsupplemented breast‐fed infants have the highest level of insufficiency (67%) compared with formula‐fed infants (2%). Factors associated with infant serum 25OHD levels at 4 months included breast feeding, supplementation, and time outside. WSW have a high prevalence of insufficiency and deficiency during pregnancy which doubles 4 months after birth. Breast‐fed infants of WSW are rarely considered at risk of vitamin D insufficiency but have high rates compared with formula‐fed infants. This is the first study to show the finding that FST I WSW have significantly lower levels of 25OHD than those with FST II–IV (difference adjusted for diet and time outside 14 (95%CI 7–21) nmol/L).     

Vitamin D status of breastfed Pakistani infants

This study was conducted to evaluate the vitamin D status of healthy breastfed Pakistani infants and their nursing mothers. Sixty-two breastfed healthy infants and their nursing mothers belonging to the upper and lower socioeconomic classes were examined. Serum 25-hydroxy vitamin D [25(OH)D], serum calcium, phosphorus and alkaline phosphatase were measured. The mean serum 25(OH)D in infants was 34.59 ± 26.56 nmol/l. Fifty-five percent of infants and 45% of mothers had very low serum 25(OH)D levels (<25 nmol/l). Significantly higher levels were found in infants of lower socioeconomic class ( p < 0:001) and in those living in mud houses ( p = 0:002) and infants > 6 months ( p < 0:001). A high prevalence of vitamin D deficiency was found in breastfed infants and nursing mothers, predominantly among those belonging to the upper socioeconomic class. Infants of the lower socioeconomic class had comparatively higher serum 25(OH)D levels, but even these levels were below the normal range for infants (90 ± 27.5 nmol/l).     

晚期早产儿脐血维生素D水平及维生素D3补充对婴幼儿行为发育的前瞻性随机对照研究（英文翻译）

目的 探讨晚期早产儿25-羟维生素D［25-hydroxyvitamin D,25(OH)D］水平及维生素D₃补充对婴幼儿神经行为发育的影响。 方法 前瞻性选取2017年6月—2020年6月收治的晚期早产儿161例为研究对象,根据脐血25(OH)D水平分为充足组（52例）、不足组（53例）、缺乏组（56例）,每组按随机数字法分为A亚组（维生素D₃ 800 IU/d）、B亚组（个体化补充维生素D₃）。分析比较各组生后3个月25(OH)D水平、纠正胎龄10个月及纠正胎龄18个月25(OH)D水平及Gesell发育量表评分的差异。 结果 生后24 h内及3个月时,不足组、缺乏组25(OH)D水平低于充足组（P<0.05）,不足组25(OH)D水平高于缺乏组（P<0.05）;缺乏组生后3个月时B亚组25(OH)D水平高于A亚组（P<0.05）。不足组和缺乏组纠正胎龄10个月、纠正胎龄18个月时Gesell发育量表5个能区得分均低于充足组（P<0.05）;缺乏组纠正胎龄10个月时言语能、纠正胎龄18个月时粗大动作能得分低于不足组（P<0.05）。缺乏组B亚组纠正胎龄10个月时适应能、纠正胎龄18个月时适应能和应物能得分高于A亚组（P<0.05）。 结论 晚期早产儿脐血25(OH)D水平存在明显差异,个体化补充维生素D方案对于纠正维生素D缺乏更为有效。出生时及婴儿早期维生素D水平对神经行为发育有一定影响。     

Subclinical hypovitaminosis D among exclusively breastfed young infants

OBJECTIVE: To determine Vitamin D status of mother-newborn diads at birth and of their exclusively breastfed (EBF) infants at 3 months. DESIGN: Longitudinal study. METHODS: Exclusively breastfed infants born at term with birth weight > 2.5 kg to normal, healthy mothers followed till 3 months. Serum calcium, phosphorous, heat labile alkaline phosphatase (HLAP) and 25(OH)D estimated in 42 mother / cord blood diads and in 35 (EBF) infants followed up at 3 months. Twenty five (OH)D < 15 ng/mL was considered low and 15 to 25 ng/mL low to normal. RESULTS: Ca, P, HLAP were significantly higher in cord blood (P < 0.001) but mean 25 (OH)D, 19.36 ng/mL was comparable to maternal level of 22.9 ng/mL (r = 0.82, P < 0.001). At 3 months only HLAP was significantly higher compared to cord blood. Higher 25 (OH)D at 3 months correlated with higher 25 (OH)D values in cord blood (r = +0.616, P < 0.001) as well as higher antenatal maternal levels (r = + 0.552, P < 0.001). Serum 25 (OH)D values < 25 ng/mL was observed in 50 % mothers, 62 % cord blood specimens and 80 % infants at 3 months. CONCLUSIONS: Subnormal maternal vitamin D status is associated with vitamin D deficiency in newborns and persists in exclusively breastfed infants.     

Vitamin D status of chronically ill or disabled children in Victoria

OBJECTIVE: To establish the percentage prevalence of hypovitaminosis D in chronically ill or disabled children in Melbourne, Australia. METHODOLOGY: A group of inpatients at the Royal Children's Hospital, Melbourne, Victoria, as identified by the primary unit, were sampled to measure serum vitamin D and parameters of bone turnover. A second group of disabled children (outpatients) were also measured to establish vitamin D status. RESULTS: Of the total population, 54.9% were found to have low serum 25 hydroxy (25OH) vitamin D levels. Of the inpatient group, 25.4% were vitamin D deficient (<30 nM/L), and 27.1% were vitamin D insufficient (30-50 nM/L). The mean 25OH vitamin D was 52.1 nM/L. Of the outpatient group, 15.4% were vitamin D deficient, whilst 42.3% were found to be insufficient. The mean vitamin D level was 41.2 nM/L. No difference attributable to intellectual versus physical disability was found. Anticonvulsant use and ambulatory status was not predictive of vitamin D status in the children examined. Of the total population, 0.05% were found to have secondary hyperparathyroidism. The mean 25OH vitamin D level of this subgroup was 30.6 nM/L. Dark skin tone was found to be significantly associated with hypovitaminosis D (P = 0.001), where all five children with dark skin tone were found to have serum 25OH vitamin D levels <50 nM/L. Of the seven disabled children (outpatients) found to be iron deficient, four had coexistent hypovitaminosis D. CONCLUSION: The percentage prevalence of hypovitaminosis D is high in both chronically ill, and physically/intellectually disabled children in Melbourne, Australia. Increased vigilance and recognition of this deficiency state is needed as an important health prevention strategy.