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/L and 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 equivalent) 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 (10 nmol/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 reported, 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.
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%）研究 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。.