Nutrition Research Division, Bureau of Nutritional Sciences, Health Products and Food Branch, Health Canada, Ottawa, ON, Canada; School of Human Nutrition, McGill University, Ste Anne de Bellevue, QC, Canada.
Nutrition Research Division, Bureau of Nutritional Sciences, Health Products and Food Branch, Health Canada, Ottawa, ON, Canada.
Bone. 2023 Oct;175:116862. doi: 10.1016/j.bone.2023.116862. Epub 2023 Jul 30.
Parathyroid hormone (PTH) is an indirect functional indicator of vitamin D status. Risk of vitamin D deficiency, assessed using circulating 25-hydroxyvitamin D (25(OH)D), is defined as <30 nmol/L by the National Academy of Medicine and alternatively <25 nmol/L in the global consensus recommendation on prevention and management of nutritional rickets.
To test PTH concentrations and the odds for elevated values according to vitamin D deficiency cut-points (<30 nmol/L, or <25 nmol/L) in newborn infants.
Healthy term-born infants (n = 858) were recruited from Montreal, Canada (2016-2019). Obstetric data were obtained from medical records, and demographic factors surveyed. Immunoassays were used to measure newborn (24-36 h) serum PTH and 25(OH)D; 25(OH)D was standardized to National Institute of Standards and Technology (NIST) standard reference materials. Serum PTH was log-transformed before comparing serum 25(OH)D groups (<30 vs. ≥30; or <25 vs. ≥25 nmol/L) using ANCOVA adjusted for infant sex, type of delivery, parity, race, and family income. The odds of elevated PTH (>71.48 pg/mL) were tested using logistic regression, adjusted for the same covariates.
Infants (50.2 % female) were 39.6 ± 1.0 weeks gestational age (mean ± SD), and 3.41 ± 0.38 kg. Median serum 25(OH)D was 45.4 (IQR 23.2) nmol/L; 20.5 % had serum 25(OH)D < 30 nmol/L, and 12.4 % <25 nmol/L. Median serum PTH was 30.72 (IQR 33.90) pg/mL, elevated in 12.7 % overall, and higher in infants born with serum 25(OH)D < 25 vs. ≥25 nmol/L (35.96 (IQR 39.20) vs. 30.36 (IQR 32.93) pg/mL, p = 0.0158). The odds of elevated PTH were higher when serum 25(OH)D was <25 nmol/L (OR 2.13, 95 % CI: 1.23, 3.69). PTH concentration and the odds of being elevated did not differ according to the 30 nmol/L cut-point.
Based on this study, the definition of vitamin D deficiency relative to bone health as set by the National Academy of Medicine (<30 nmol/L) exceeds the threshold at which PTH is elevated in newborn infants.
甲状旁腺激素（PTH）是维生素 D 状态的间接功能指标。使用循环 25-羟维生素 D（25（OH）D）评估维生素 D 缺乏的风险，美国国家医学院将其定义为 <30 nmol/L，全球预防和管理营养性佝偻病的共识建议中则定义为 <25 nmol/L。
检测维生素 D 缺乏切点（<30 nmol/L 或 <25 nmol/L）时新生儿的甲状旁腺激素浓度和升高值的可能性。
2016 年至 2019 年，从加拿大蒙特利尔招募了 858 名健康足月出生的婴儿。从病历中获取产科数据，并调查人口统计学因素。使用免疫测定法测量新生儿（24-36 小时）血清 PTH 和 25（OH）D；将 25（OH）D 标准化为美国国家标准与技术研究院（NIST）标准参考物质。使用 ANCOVA 比较血清 25（OH）D 组（<30 与≥30；或<25 与≥25 nmol/L）之前，对新生儿血清 PTH 进行对数转换，调整婴儿性别、分娩方式、产次、种族和家庭收入等因素。使用 logistic 回归测试 PTH 升高（>71.48 pg/mL）的可能性，调整了相同的协变量。
婴儿（50.2%为女性）的胎龄为 39.6±1.0 周（平均值±标准差），体重为 3.41±0.38 千克。中位血清 25（OH）D 为 45.4（IQR 23.2）nmol/L；20.5%的婴儿血清 25（OH）D <30 nmol/L，12.4%的婴儿血清 25（OH）D <25 nmol/L。中位血清 PTH 为 30.72（IQR 33.90）pg/mL，总体升高 12.7%，与血清 25（OH）D <25 与≥25 nmol/L 的婴儿相比更高（35.96（IQR 39.20）与 30.36（IQR 32.93）pg/mL，p=0.0158）。当血清 25（OH）D <25 nmol/L 时，PTH 升高的可能性更高（OR 2.13，95%CI：1.23，3.69）。PTH 浓度和升高的可能性与 30 nmol/L 切点无关。
根据这项研究，美国国家医学院（<30 nmol/L）设定的维生素 D 缺乏与骨骼健康相关的定义超过了新生儿甲状旁腺激素升高的阈值。
