Shengli Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, People's Republic of China.
Department of Geriatric Medicine, Fujian Provincial Hospital, Fuzhou, Fujian, People's Republic of China.
Clin Interv Aging. 2022 Jul 7;17:1057-1068. doi: 10.2147/CIA.S370930. eCollection 2022.
Intrinsic capacity (IC) reflects the overall health status of older adults and has great public health significance. But few studies described the related biomarkers for IC. The aim of this study was to investigate the association between homocysteine (Hcy) and IC in older adults.
This cross-sectional study included 1927 community-dwelling Chinese older adults aged 60-98 years from May 2020 to December 2020. Data were collected through interviews, physical examinations, and laboratory tests. IC involved five domains of cognition, locomotion, sensory, vitality, and psychology evaluated by the Mini-cog scale, 4-m walk test, self-reported visual and hearing conditions, MNA-SF scale, and GDS-4 scale, respectively. The score of each domain dichotomized as 0 (normal) and 1 (impaired) was added together to an IC total score. Low IC was defined as a score of 3-5, and high IC as 0-2. Hcy was measured by a two-reagent enzymatic assay. A restricted cubic spline regression model was used to explore the non-linear relationship between Hcy and low IC.
Hcy was higher in the low IC group than in the high IC group. Restricted cubic spline analysis revealed a J-shaped nonlinear association between Hcy and low IC. The risk of IC decline was slowly decreased until 8.53 µmol/L of Hcy (OR=0.753, 95% CI=0.520-1.091, P=0.132), and increased with elevations of per 5 µmol/L Hcy afterwards (OR=1.176, 95% CI=1.059-1.327, P=0.005). Among the five domains of IC, Hcy had ORs of 1.116 (1.009-1.247) for cognition impairment, 1.167 (1.055-1.305) for vitality, and 1.160 (1.034-1.303) for psychology per 5 µmol/L increase in Hcy above the change point. Additional sensitivity analysis also demonstrated the nonlinear association between Hcy and low IC.
Hcy had a J-shaped association with low IC. Higher Hcy (Hcy ≥8.53µmol/L) might provide clinical implications for early identifying the risk of low IC.
内在能力（IC）反映了老年人的整体健康状况，具有重要的公共卫生意义。但很少有研究描述与 IC 相关的生物标志物。本研究旨在探讨老年人同型半胱氨酸（Hcy）与 IC 的关系。
这是一项横断面研究，纳入了 2020 年 5 月至 12 月期间年龄在 60-98 岁的 1927 名社区居住的中国老年人。数据通过访谈、体检和实验室测试收集。IC 涉及认知、运动、感觉、活力和心理五个领域，分别通过 Mini-cog 量表、4 米步行测试、自我报告的视觉和听觉状况、MNA-SF 量表和 GDS-4 量表进行评估。每个领域的评分均分为 0（正常）和 1（受损），并加总为 IC 总分。低 IC 定义为 3-5 分，高 IC 定义为 0-2 分。Hcy 采用双试剂酶法测定。采用受限立方样条回归模型探讨 Hcy 与低 IC 之间的非线性关系。
低 IC 组的 Hcy 水平高于高 IC 组。受限立方样条分析显示，Hcy 与低 IC 之间存在 J 形非线性关系。直到 Hcy 达到 8.53µmol/L 时，IC 下降的风险才缓慢下降（OR=0.753，95%CI=0.520-1.091，P=0.132），此后每升高 5µmol/L Hcy，风险就会增加（OR=1.176，95%CI=1.059-1.327，P=0.005）。在 IC 的五个领域中，Hcy 每增加 5µmol/L，认知障碍的 OR 为 1.116（1.009-1.247），活力为 1.167（1.055-1.305），心理为 1.160（1.034-1.303）。敏感性分析还进一步证实了 Hcy 与低 IC 之间的非线性关系。
Hcy 与低 IC 呈 J 形关联。较高的 Hcy（Hcy≥8.53µmol/L）可能为早期识别低 IC 风险提供临床意义。
