A Cross-sectional Analysis of Serum Irisin Levels in Individuals with Thyroid Dysfunction Compared to the Control...

Irisin is an adipo-myokine that is released by proteolytic cleavage of the membrane protein, fibronectin type III domain-containing protein 5. Irisin is responsible for the process of browning of white adipose tissue and is known to impact thermogenesis. Owing to the similarities in action between irisin and thyroid hormones, identifying these mutual influences in the body seems to be imperative.

This study aimed at investigating the association between serum irisin levels and thyroid dysfunction.

This cross-sectional study was conducted in the Department of Endocrinology, Ramaiah Medical College and Hospital, Bengaluru, India, from January 1, 2025, to May 1, 2025, among individuals greater than 18 years old with new-onset hypothyroidism or hyperthyroidism and euthyroid age- and sex-matched control population who consented to the study. Serum irisin levels were assayed and compared between groups (hypothyroid, hyperthyroid, and control). Statistical analysis was performed using SPSS version 22 and Microsoft Excel (2016). An independent t -test was used as a significant test to identify the mean difference between two quantitative variables. Categorical data were represented in frequencies and proportions. Continuous data were expressed as mean and standard deviation. Correlations were performed with the Pearson Correlation coefficient. P <0.05 was considered statistically significant.

The study included 23 euthyroid controls and 48 individuals with thyroid dysfunction (28 hyperthyroid; 20 hypothyroid). A significant difference was noted in serum irisin levels between controls and individuals with thyroid dysfunction ( P = 0.03). Further analysis depicted hypothyroid individuals showing a strong positive correlation between irisin and thyroid-stimulating hormone levels ( r = 0.382, P = 0.04).

This study highlights the positive correlation of irisin levels in hypothyroid individuals, speculating on the possibility of irisin's role in physiological adaptations in individuals with hypothyroidism.