Nguyen Leonard T, Buse Joshua D, Baskin Leland, Sadrzadeh S M Hossein, Naugler Christopher
Department of Pathology and Laboratory Medicine, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr NW, Calgary, Alberta T2N 4N1, Canada.
Department of Pathology and Laboratory Medicine, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr NW, Calgary, Alberta T2N 4N1, Canada; Calgary Laboratory Services, 3535 Research Rd NW, Calgary, Alberta T2L 2K8, Canada.
Clin Biochem. 2017 Dec;50(18):1237-1242. doi: 10.1016/j.clinbiochem.2017.09.018. Epub 2017 Sep 23.
Serum iron is an important clinical test to help identify cases of iron deficiency or overload. Fluctuations caused by diurnal variation and diet are thought to influence test results, which may affect clinical patient management. We examined the impact of these preanalytical factors on iron concentrations in a large community-based cohort.
Serum iron concentration, blood collection time, fasting duration, patient age and sex were obtained for community-based clinical testing from the Laboratory Information Service at Calgary Laboratory Services for the period of January 2011 to December 2015.
A total of 276,307 individual test results were obtained. Iron levels were relatively high over a long period from 8:00 to 15:00. Mean concentrations were highest at blood collection times of 11:00 for adult men and 12:00 for adult women and children, however iron levels peaked as late as 15:00 in teenagers. With regard to fasting, iron levels required approximately 5h post-prandial time to return to a baseline, except for children and teenage females where no significant variation was seen until after 11h fasting. After 10h fasting, iron concentrations in all patient groups gradually increased to higher levels compared to earlier fasting times.
Serum iron concentrations remain reasonably stable during most daytime hours for testing purposes. In adults, blood collection after 5 to 9h fasting provides a representative estimate of a patient's iron levels. For patients who have fasted overnight, i.e. ≥12h fasting, clinicians should be aware that iron concentrations may be elevated beyond otherwise usual levels.
血清铁是一项重要的临床检查，有助于识别缺铁或铁过载病例。昼夜变化和饮食引起的波动被认为会影响检测结果，这可能会影响临床患者管理。我们在一个大型社区队列中研究了这些分析前因素对铁浓度的影响。
从卡尔加里实验室服务公司的实验室信息服务部门获取2011年1月至2015年12月期间基于社区临床检测的血清铁浓度、采血时间、禁食时长、患者年龄和性别。
共获得276307份个体检测结果。从8:00到15:00的很长一段时间内铁水平相对较高。成年男性在11:00采血时平均浓度最高，成年女性和儿童在12:00采血时平均浓度最高，然而青少年的铁水平直到15:00才达到峰值。关于禁食，除儿童和青少年女性在禁食11小时后才出现显著变化外，铁水平在餐后约5小时恢复到基线。禁食10小时后，所有患者组的铁浓度与早期禁食时间相比逐渐升高到更高水平。
为了检测目的，血清铁浓度在大多数白天时间内保持相当稳定。对于成年人，禁食5至9小时后采血可提供患者铁水平的代表性估计值。对于禁食过夜（即禁食≥12小时）的患者，临床医生应意识到铁浓度可能会升高到高于通常的水平。
