Increased leptin/adiponectin ratio relates to low-normal thyroid function in metabolic syndrome.

Area of Science:

• Endocrinology
• Metabolic Syndrome Research
• Cardiovascular Disease Risk Factors

Background:

• Subclinical thyroid dysfunction may increase atherosclerosis risk.
• The leptin/adiponectin (L/A) ratio is a marker for cardiovascular disease and adipose tissue dysfunction.
• The association between low-normal thyroid function and the L/A ratio is not well understood.

Purpose of the Study:

• To investigate the relationship between thyroid function (TSH and free T4) and the L/A ratio in euthyroid individuals.
• To explore these relationships in subjects with and without metabolic syndrome (MetS).

Main Methods:

• Cross-sectional study of 67 euthyroid subjects with MetS and 86 euthyroid subjects without MetS.
• Measured thyroid stimulating hormone (TSH), free thyroxine (free T4), leptin, and adiponectin.
• Analyzed correlations between hormone levels, the L/A ratio, and MetS components.

Main Results:

• No significant correlation was found between leptin or adiponectin and TSH or free T4 in either group.
• In the overall cohort, high-sensitivity C-reactive protein (hs-CRP) positively correlated with the L/A ratio.
• A positive correlation between the L/A ratio and TSH was observed specifically in subjects with MetS, persisting after adjustments.

Conclusions:

• Within the euthyroid range, elevated TSH is associated with an increased L/A ratio in individuals with MetS.
• This finding suggests a potential link between thyroid function within the normal range and adipocyte dysfunction in the context of MetS.