Uyar Galip Can, Kılıç Mustafa Kemal
Department of Medical Oncology, Ankara Etlik City Hospital, Yenimahalle, Ankara, Turkey.
Department of Internal Medicine, Ankara Training and Research Hospital, Ankara, Turkey.
BMC Geriatr. 2024 Dec 31;24(1):1051. doi: 10.1186/s12877-024-05643-5.
BACKGROUND AND RATIONALE: Thyroid dysfunction in older adults often mimics the signs of aging, impacting metabolism and overall physiological balance. While age-related chronic conditions have been extensively studied, the relationship between thyroid function and frailty remains underexplored.
This study aimed to evaluate the effects of thyroid dysfunction on frailty among individuals aged 65 years and older. Thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), and thyroid peroxidase antibody (anti-TPO) levels were analyzed. The study further examined the correlation between thyroid dysfunction, chronic diseases, sociodemographic factors, and optimal TSH levels in relation to frailty, using the Study of Osteoporotic Fractures (SOF), Edmonton Frail Scale (EFS), and FRAIL scales.
This cross-sectional study included 220 older adults with either treated or untreated thyroid dysfunction. Comprehensive geriatric assessments were conducted, including detailed medical histories, sociodemographic data collection, and thyroid function tests. Frailty was assessed using the SOF, EFS, and FRAIL scales. Multivariate logistic regression analyses were performed to identify significant associations between thyroid parameters and frailty.
The median age of participants was 73 years, and 68.2% (n = 150) were women. Frailty prevalence was significantly higher in individuals with abnormal TSH levels (outside the 0.5-6 mIU/L range). Lower fT3 levels and the fT3/fT4 ratio were significantly associated with frailty, particularly as assessed by the SOF and EFS scales. In contrast, the FRAIL scale revealed a significant association between increased frailty and lower fT3 levels only. Subgroup analysis indicated that in individuals aged ≥ 80 years, a lower fT3/fT4 ratio was consistently associated with frailty across all frailty scales, whereas in those aged < 80 years, lower TSH levels showed a strong association with frailty as assessed by the FRAIL scale. These findings underscore age-specific variations in the relationship between thyroid function and frailty.
This study highlights the significant impact of thyroid dysfunction on frailty in older adults. Lower fT3 levels and the fT3/fT4 ratio emerged as key indicators of increased frailty, particularly on the SOF and EFS scales. Subgroup analysis further emphasized the importance of age-specific assessments, with a lower fT3/fT4 ratio being a critical indicator of frailty in individuals aged ≥ 80 years, while lower TSH levels were significant in those aged < 80 years. Abnormal TSH levels were strongly associated with frailty on the SOF scale, suggesting the need to consider thyroid dysfunction as a modifiable risk factor. Additionally, factors such as age, sex, education, thyroid medication use, and comorbidities influenced frailty status. Incorporating thyroid function tests into frailty assessments could enhance early identification and targeted interventions for at-risk older adults, particularly when age-specific thresholds are applied.
背景与原理：老年人甲状腺功能障碍常与衰老迹象相似，影响新陈代谢和整体生理平衡。虽然与年龄相关的慢性病已得到广泛研究，但甲状腺功能与衰弱之间的关系仍未得到充分探索。
本研究旨在评估甲状腺功能障碍对65岁及以上老年人衰弱的影响。分析了促甲状腺激素（TSH）、游离三碘甲状腺原氨酸（fT3）、游离甲状腺素（fT4）和甲状腺过氧化物酶抗体（抗TPO）水平。本研究还使用骨质疏松性骨折研究（SOF）、埃德蒙顿衰弱量表（EFS）和衰弱量表，进一步探讨了甲状腺功能障碍、慢性病、社会人口学因素与衰弱相关的最佳TSH水平之间的相关性。
这项横断面研究纳入了220名患有已治疗或未治疗甲状腺功能障碍的老年人。进行了全面的老年医学评估，包括详细的病史、社会人口学数据收集和甲状腺功能测试。使用SOF、EFS和衰弱量表评估衰弱情况。进行多变量逻辑回归分析，以确定甲状腺参数与衰弱之间的显著关联。
参与者的中位年龄为73岁，68.2%（n = 150）为女性。TSH水平异常（超出0.5 - 6 mIU/L范围）的个体衰弱患病率显著更高。较低的fT3水平和fT3/fT4比值与衰弱显著相关，特别是通过SOF和EFS量表评估时。相比之下，衰弱量表仅显示衰弱增加与较低的fT3水平之间存在显著关联。亚组分析表明，在年龄≥80岁的个体中，较低的fT3/fT4比值在所有衰弱量表中均与衰弱持续相关，而在年龄<80岁的个体中，较低的TSH水平在通过衰弱量表评估时与衰弱有很强的关联。这些发现强调了甲状腺功能与衰弱之间关系的年龄特异性差异。
本研究强调了甲状腺功能障碍对老年人衰弱的重大影响。较低的fT3水平和fT3/fT4比值成为衰弱增加的关键指标，特别是在SOF和EFS量表上。亚组分析进一步强调了年龄特异性评估的重要性，较低的fT3/fT4比值是年龄≥80岁个体衰弱的关键指标，而较低的TSH水平在年龄<80岁个体中具有显著意义。异常的TSH水平在SOF量表上与衰弱密切相关，表明需要将甲状腺功能障碍视为一个可改变的风险因素。此外，年龄、性别、教育程度、甲状腺药物使用和合并症等因素影响衰弱状态。将甲状腺功能测试纳入衰弱评估可以加强对高危老年人的早期识别和针对性干预，特别是当应用年龄特异性阈值时。
