Kini Geogry Peter, Young Brian, Herbison Peter, Schultz Michael
Gastroenterology, Dunedin Hospital, Great King Street, Dunedin 9054, New Zealand.
N Z Med J. 2014 May 23;127(1394):51-9.
Vitamin D has immune modulating effects and normal to high levels might be correlated with less severe Crohn's disease (CD). We aimed to review seasonal vitamin D levels in CD patients in correlation with disease activity.
CD patients were identified from an inflammatory bowel disease (IBD) database and given two questionnaires enquiring about vitamin D supplementation, sun exposure, sunblock application and symptoms to complete the CDAI. Participants were examined and serum 25-OH vitamin D [25(OH)D] levels and haematocrit were determined in winter (06/2011-09/2011) and summer (12/2011-03/2012). Patients taking vitamin D supplements or with extensive small bowel resection were excluded.
32 patients (19 women, mean age 39 plus or minus 16 years, range 18-73 years), from Dunedin, New Zealand (45 degrees 52' S, 170 degrees 30' E) consented to participate in the study. Of these, three took vitamin D supplements and were excluded. In winter 76% of the participants had serum 25(OH)D levels classified as deficient (<50 nmol/L) and all of them had insufficient 25(OH)D levels (<75 nmol/L). In summer, serum 25(OH)D levels were deficient only in 10% but insufficient in 55% of the participants. Mean serum 25(OH)D level was 35.9 nmol/L (norm 50-150nmol/L) in winter (range 5-67, SD 17.5) and 69.6 nmol/L in summer (range 13-119, SD 19.0) (p<0.0005). There was no significant difference in the seasonal levels of serum 25(OH)D between male and female participants (p=0.601). Mean CDAI score was 103.9 in winter (range -10-262, SD 76.9) and 90.2 in summer (range -13-331, SD 84.0) (p=0.365). A mixed-effects regression analysis showed no statistically significant correlation between seasonal levels of serum 25(OH)D and CDAI (p=0.612) among our study participants.
Suboptimal levels of serum 25(OH)D were found in the majority of our study participants particularly in winter and they would benefit from supplementation. Our study showed no statistically significant correlation between seasonal serum 25(OH)D levels and CD activity. Given the limitations of the study, the role of 25(OH)D as a predictor of disease activity could not be clearly concluded.
维生素D具有免疫调节作用，正常至高维生素D水平可能与病情较轻的克罗恩病（CD）相关。我们旨在探讨CD患者的季节性维生素D水平与疾病活动度之间的相关性。
从炎症性肠病（IBD）数据库中识别出CD患者，并给予两份问卷，询问维生素D补充情况、阳光暴露、防晒霜使用情况以及症状，以完成CDAI。对参与者进行检查，并在冬季（2011年6月至2011年9月）和夏季（2011年12月至2012年3月）测定血清25-羟基维生素D [25(OH)D]水平和血细胞比容。排除服用维生素D补充剂或接受广泛小肠切除术的患者。
来自新西兰达尼丁（南纬45度52分，东经170度30分）的32例患者（19名女性，平均年龄39±16岁，范围18 - 73岁）同意参与本研究。其中，3例服用维生素D补充剂，被排除。冬季，76%的参与者血清25(OH)D水平被分类为缺乏（<50 nmol/L），且所有人的25(OH)D水平均不足（<75 nmol/L）。夏季，仅10%的参与者血清25(OH)D水平缺乏，但55%的参与者水平不足。冬季血清25(OH)D平均水平为35.9 nmol/L（正常范围50 - 150 nmol/L）（范围5 - 67，标准差17.5），夏季为69.6 nmol/L（范围13 - 119，标准差19.0）（p<0.0005）。男性和女性参与者之间血清25(OH)D的季节性水平无显著差异（p = 0.601）。冬季CDAI平均评分为103.9（范围 - 10 - 262，标准差76.9），夏季为90.2（范围 - 13 - 331，标准差84.0）（p = 0.365）。混合效应回归分析显示，在我们的研究参与者中，血清25(OH)D的季节性水平与CDAI之间无统计学显著相关性（p = 0.612）。
我们的大多数研究参与者血清25(OH)D水平欠佳，尤其是在冬季，补充维生素D对他们有益。我们的研究表明，季节性血清25(OH)D水平与CD活动度之间无统计学显著相关性。鉴于本研究的局限性，无法明确得出25(OH)D作为疾病活动度预测指标的作用。
