Association between sensitivity to thyroid hormone indices and frailty in the elderly: a cross-sectional study

Area of Science:

• Gerontology
• Endocrinology
• Biochemistry

Background:

• Frailty is a common geriatric syndrome with complex, multi-systemic effects.
• Existing research on the link between thyroid function and frailty presents conflicting findings.
• Accurate indicators for evaluating frailty remain a challenge in clinical practice.

Purpose of the Study:

• To investigate the association between thyroid hormone sensitivity indices and frailty in elderly individuals.
• To evaluate the utility of these indices as potential biomarkers for frailty assessment.

Main Methods:

• 1030 Chinese elderly participants were assessed for frailty using the FRAIL scale.
• Thyroid hormone sensitivity indices, including TT4RI, TSHI, TFQI, and FT3/FT4, were calculated.
• Multivariate logistic regression analysis was employed to determine the association between frailty and thyroid markers.

Main Results:

• Frail individuals showed significantly lower levels of FT3 and TSH compared to non-frail individuals.
• Central thyroid hormone sensitivity indices, TFQI(FT3), and peripheral sensitivity index, FT3/FT4, were also reduced in the frail group.
• Adjusted analyses revealed a negative correlation between FT3, TSHI, TFQI(FT3), FT3/FT4, and the FRAIL scale score.

Conclusions:

• Decreased serum FT3 and TSH levels are observed in frail elderly individuals.
• Reduced central (TSHI, TFQI(FT3)) and peripheral (FT3/FT4) thyroid hormone sensitivity indices are associated with frailty.
• Thyroid measures like FT3, TFQI(FT3), and FT3/FT4 may serve as valuable, easily assessable indicators for frailty evaluation.