García-Esquinas E, Carrasco-Rios M, Ortolá R, Sotos Prieto M, Pérez-Gómez B, Gutiérrez-González E, Banegas J R, Queipo R, Olmedo P, Gil F, Tellez-Plaza M, Navas-Acien A, Pastor-Barriuso R, Rodríguez-Artalejo F
Department of Preventive Medicine and Public Health. School of Medicine. Universidad Autónoma de Madrid, Madrid. Spain; IdiPaz (Instituto de Investigación Sanitaria Hospital Universitario La Paz), Madrid, Spain; CIBERESP (CIBER of Epidemiology and Public Health), Madrid, Spain.
Department of Preventive Medicine and Public Health. School of Medicine. Universidad Autónoma de Madrid, Madrid. Spain.
Redox Biol. 2021 Jan;38:101819. doi: 10.1016/j.redox.2020.101819. Epub 2020 Nov 28.
Selenium (Se) is a trace element with a narrow safety margin.
To evaluate the cross-sectional and longitudinal dose-response association between Se exposure and measures of impaired physical function and disability in older adults.
NHANES 2011-2014 cross-sectional (US, n = 1733, age ≥60 years) and Seniors-ENRICA-2 2017-2019 cross-sectional and longitudinal (Spain, n = 2548 and 1741, respectively, age ≥65 years) data were analyzed. Whole blood and serum Se levels were measured using inductively coupled plasma-mass spectrometry. Lower-extremity performance was assessed with the Short Physical Performance Battery, and muscle weakness with a dynamometer. Incident mobility and agility limitations, and disability in instrumental activities of daily living (IADL) were ascertained with standardized questionnaires. Analyses were adjusted for relevant confounders, including physical activity. Results across studies were pooled using random-effects meta-analysis.
Meta-analyzed odds ratios (95% confidence interval) per log2 increase in whole blood Se were 0.54 (0.32; 0.76) for weakness, 0.59 (0.34; 0.83) for impaired lower-extremity performance, 0.48 (0.31; 0.68) for mobility limitations, 0.71 (0.45; 0.97) for agility limitations, and 0.34 (0.12; 0.56) for disability in at least one IADL. Analyses for serum Se in NHANES showed similar results. Findings suggest the inverse association with grip strength is progressive below 140 μg/L (p-value for non-linear trend in the Seniors-ENRICA-2 study = 0.13), and above 140 μg/L (p-value for non-linear trend in NHANES = 0.11). In the Seniors-ENRICA-2 cohort, with a 2.2 year follow-up period, a doubling in baseline Se levels were associated with a lower incidence of weakness [odds ratio (95% confidence interval): 0.45 (0.22; 0.91)], impaired lower-extremity performance [0.63 (0.32; 1.23)], mobility [0.43 (0.21; 0.91)] and agility [0.38 (0.18; 0.78)] limitations.
In US and Spanish older adults, Se concentrations were inversely associated with physical function limitations. Further studies are needed to elucidate underlying mechanisms.
硒（Se）是一种安全边际较窄的微量元素。
评估老年人中硒暴露与身体功能受损及残疾指标之间的横断面和纵向剂量反应关联。
分析了2011 - 2014年美国国家健康与营养检查调查（NHANES）的横断面数据（美国，n = 1733，年龄≥60岁）以及2017 - 2019年西班牙老年人ENRICA - 2研究的横断面和纵向数据（西班牙，分别为n = 2548和1741，年龄≥65岁）。使用电感耦合等离子体质谱法测量全血和血清硒水平。通过简短身体性能测试评估下肢功能，用测力计评估肌肉力量。通过标准化问卷确定突发的行动能力和敏捷性受限情况以及日常生活工具性活动（IADL）中的残疾情况。分析对包括身体活动在内的相关混杂因素进行了调整。各研究结果使用随机效应荟萃分析进行汇总。
全血硒每增加log2，荟萃分析得到的优势比（95%置信区间）为：肌肉力量减弱为0.54（0.32；0.76），下肢功能受损为0.59（0.34；0.83），行动能力受限为0.48（0.31；0.68），敏捷性受限为0.71（0.45；0.97），至少一项IADL残疾为0.34（0.12；0.56）。NHANES中血清硒的分析显示了类似结果。研究结果表明，低于140μg/L时与握力的负相关是渐进性的（老年人ENRICA - 2研究中非线性趋势的p值 = 0.13），高于140μg/L时也是如此（NHANES中非线性趋势的p值 = 0.11）。在老年人ENRICA - 2队列中，经过2.2年的随访期，基线硒水平翻倍与肌肉力量减弱[优势比（95%置信区间）：0.45（0.22；0.91）]、下肢功能受损[0.63（0.32；1.23）]、行动能力[0.43（0.21；0.91）]和敏捷性[0.38（0.18；0.78）]受限的发生率较低相关。
在美国和西班牙的老年人中，硒浓度与身体功能受限呈负相关。需要进一步研究以阐明潜在机制。
