Vitamin D status of Māori and non-Māori octogenarians in New Zealand: a cohort study (LiLACS NZ)

Abstract

BACKGROUND AND OBJECTIVES: This study assessed vitamin D status and its determinants in a cohort of octogenarians living within New Zealand’s Bay of Plenty and Lakes Districts.

METHODS AND STUDY DESIGN: Serum 25-hydroxyvitamin D [25(OH)D] concentration was measured in 209 Māori (aged 80-90 years) and 357 non-Māori (85 years), along with demographic, lifestyle, supplement use and other health data.

RESULTS: Mean [95% CI] 25(OH)D concentration was 69 [67 to 72] nmol/L, with 15% >100 nmol/Land 6 individuals >150 nmol/L. Concentrations in Māori (59 [55 to 62] 4 nmol/L) were lower than in non-Māori (75 [72 to 78] nmol/L; p<0.001), a difference maintained when adjusted for day-of-year measured. Vitamin D supplementation was reported by 98 participants (18%): including a greater proportion of women (24%) than men (11%; p<0.001) and of non-Māori (24%) than Māori (7%; p<0.001). Of those taking vitamin D, 49% took high oral doses (≥25 μg/day or equiva-lent) and five individuals took >50 μg/day. Vitamin D supplement use strongly and independently predicted seasonally adjusted 25(OH)D concentration and was associated with 28 nmol/L higher levels than non-use. Other predictors included Māori ethnicity (10nmol/L lower concentration than for non-Māori), and female gender (11 nmol/L lower).

CONCLUSIONS: Vitamin D status in New Zealand octogenarians appears higher than previously re-ported, particularly in non-Māori compared to Māori. Prescribed and non-prescribed oral vitamin D supplementation is prevalent in this group and a strong indicator of vitamin D status.

新西兰毛利族和非毛利族八旬老人维生素D状况： 一项

队列研究背景与目的：本研究评估了队列研究中 生活在新西兰湾和湖泊区域的八旬老人的维生素D状况及其决定因素。

方法与研究设计： 测量209名毛利人（80-90岁）和357名非毛利人（85岁）的血清25-羟维生素D（25(OH)D）的浓度，同时收集研究对象的体格测量指标、生活方式、 补充剂的应用和其它健康资料。

结果：

平均25(OH)D浓度为69（95% CI：67-72）nmol/L，其中15%的研究对象>100 nmol/L，6个研究对象>150 nmol/L。毛利人的25(OH)D浓度（59 nmol/L，95% CI: 55-62 nmol/L）低于非毛利人（75 nmol/L，95% CI：72-78 nmol/L，p<0.001），校正测量日期后，差异仍然存在。98名（占18%）研对象报告补充了维生素D，女性中补充者所占的比例（24%）高于男性（11%，p<0.001），非毛利人中补充者所占的比例高于毛利人。补充维生素D的人中，49%的人摄入高剂量（每天≥25 μg或相当剂量），5个研究对象每天摄入维生素D≥50 μg。维生素D补充剂的应用能够强而独立地预测季节校正的25(OH)D浓度，并且使用者比不用者高28 nmol/L。其它预测指标包括毛利族（比非毛利族低10 nmol/L）和女性性别（比男性低11 nmol/L）。

结论： 新西兰八旬老人维 生素D浓度高于以前的报告，尤其是非毛利人。这个人群中处方和非处方口服维生素D补充剂普遍存在，并且是维生素状态的强预测指标。