TY - JOUR
T1 - High-normal TSH values in obesity depends on adipose tissue rather than insulin resistance
AU - Muscogiuri, Giovanna
AU - Sorice, Gianpio
AU - Mezza, Teresa
AU - Prioletta, Annamaria
AU - Lassandro, Anna Pia
AU - Pirronti, Tommaso
AU - Della Casa, Silvia
AU - Pontecorvi, Alfredo
AU - Giaccari, Andrea
PY - 2012
Y1 - 2012
N2 - Clinical evidences reported subclinical alterations of thyroid function in obesity, although the relationship between thyroid status and obesity remains unclear. We cross-sectionally investigated the influence of metabolic features on hypothalamic-pituitary-
thyroid axis in obesity. We enrolled 60 euthyroid subjects with no history of type 2 diabetes mellitus and assessed the relationship of thyroid function with insulin-resistance, measured using
euglycemic clamp, and abdominal fat volume, quantified by CT-Scan.
TSH correlated with BMI (r=0.46;p=0.02), both visceral (r=0.58;p=0.02) and subcutaneous adipose
tissue volumes (r=0.43;p=0.03) and insulin-resistance (inverse relationship with insulin-sensitivity -
glucose uptake: r=-0.40 p=0.04). After performing multivariate regression, visceral adipose tissue volume was found to be the most powerful predictor of TSH (β=3.05;p=0.01), whereas glucose
uptake, HDL cholesterol, LDL cholesterol, subcutaneous adipose tissue volume and triglycerides
were not. To further confirm the hypothesis that high-normal TSH values could be dependent on adipose tissue, and not on insulin-resistance, we restricted our analyses to moderately obese subjects BMI ranging 30-35 kg/ m2. This subgroup was then divided in insulin-resistant and insulinsensitive
according to the glucose uptake (≤ or > 5 mg·kg-1·min-1, respectively). We did not find any statistical difference in TSH (insulin-resistant: 1.62±0.65 μU/mL vs. insulin-sensitive:1.46 ±
0.48;p=NS) and BMI (insulin-resistant: 32.2 ± 1.6 kg/m2 vs. insulin-sensitive:32.4 ± 1.4;p=NS), thus confirming absence of correlation between thyroid function and insulin-sensitivity per se. Our study suggests that the increase in visceral adipose tissue is the best predictor of subclinical thyroid dysfunction in obesity, independently from the eventual concurrent presence of insulin resistance.
AB - Clinical evidences reported subclinical alterations of thyroid function in obesity, although the relationship between thyroid status and obesity remains unclear. We cross-sectionally investigated the influence of metabolic features on hypothalamic-pituitary-
thyroid axis in obesity. We enrolled 60 euthyroid subjects with no history of type 2 diabetes mellitus and assessed the relationship of thyroid function with insulin-resistance, measured using
euglycemic clamp, and abdominal fat volume, quantified by CT-Scan.
TSH correlated with BMI (r=0.46;p=0.02), both visceral (r=0.58;p=0.02) and subcutaneous adipose
tissue volumes (r=0.43;p=0.03) and insulin-resistance (inverse relationship with insulin-sensitivity -
glucose uptake: r=-0.40 p=0.04). After performing multivariate regression, visceral adipose tissue volume was found to be the most powerful predictor of TSH (β=3.05;p=0.01), whereas glucose
uptake, HDL cholesterol, LDL cholesterol, subcutaneous adipose tissue volume and triglycerides
were not. To further confirm the hypothesis that high-normal TSH values could be dependent on adipose tissue, and not on insulin-resistance, we restricted our analyses to moderately obese subjects BMI ranging 30-35 kg/ m2. This subgroup was then divided in insulin-resistant and insulinsensitive
according to the glucose uptake (≤ or > 5 mg·kg-1·min-1, respectively). We did not find any statistical difference in TSH (insulin-resistant: 1.62±0.65 μU/mL vs. insulin-sensitive:1.46 ±
0.48;p=NS) and BMI (insulin-resistant: 32.2 ± 1.6 kg/m2 vs. insulin-sensitive:32.4 ± 1.4;p=NS), thus confirming absence of correlation between thyroid function and insulin-sensitivity per se. Our study suggests that the increase in visceral adipose tissue is the best predictor of subclinical thyroid dysfunction in obesity, independently from the eventual concurrent presence of insulin resistance.
KW - abdominal obesity
KW - insulin resistance
KW - subcutaneous adipose tissue
KW - visceral fat
KW - abdominal obesity
KW - insulin resistance
KW - subcutaneous adipose tissue
KW - visceral fat
UR - http://hdl.handle.net/10807/24657
UR - http://www.nature.com/oby/index.html
M3 - Article
SN - 1930-7381
SP - N/A-N/A
JO - Obesity
JF - Obesity
ER -