Analysing Association Between Anthropometric Indicators of Insulin Resistance and Insulin-Like Growth Factor-1 in Patients With Nodular Goiter

Abstract

Publications suggesting that thyroid nodule might be associated with insulin resistance (IR) and metabolic syndrome are quite interesting. In a very recent report, increased thyroid volume and nodule prevalence were also reported in patients with IR in an iodine-sufficient area []. The purpose of the work is to analyze the association between anthropometric indicators IR and IGF-1 in patients with nodular goiter. 
 Materials and methods. During the study the authors examined 73 patients with euthyroid single-node (n = 34) and multinodular goiter (n = 39) aged 17 to 74 years (mean - (51.0 ± 10.6) years), determining WC, WC / HC, BMI, WHtR, ABSI, BFD, BRI, CI, AVI, BAI, IGF-1, TSH, fT4, fT3. Thyroid volume, its structure, number, size and location of foci was assessed by an ultrasonic complex Aloka SSD-1100 (Japan), using a linear sensor 7.5 MHz.
 Results and their discussion. In the total number of patients with nodular goiter IGF-1 is nonlinearly negatively associated with BMI (r = -0.30; P = 0.016), WC (r = -0.26; P = 0.036), WHtR (r = -0.30) ; P = 0.020), AVI (r = -0.27; P = 0.03), ABSI (r = -0.31; P = 0.015), nonlinear positive with BFD (r = 0.27; P = 0.033) ), BRI (r = 0.29; P = 0.02) and linearly positive with BAI (r = 0.36; P = 0.004); thyroid volume is linearly positively associated with age (r = 0.35; P = 0.009), nonlinearly positively with WC / HC (r = 0.43; P = 0.001), BFD (r = 0.26; P = 0.06 ) and CI (r = 0.31; P = 0.02).
 In patients with nodular goiter with BMI≥35 kg / m2 thyroid volume is linearly positively associated with BMI (r = 0.71; P = 0.049). In patients with nodular goiter with IRF-1 above the sex-age norm, thyroid volume is nonlinearly positively associated with WC / HC (r = 0.71; P = 0.01), BAI (r = 0.66; P = 0.03 ) and nonlinearly negative with BFD (r = -0.52; P = 0.01). It has been found that BAI explains 82.37% of the variance of IGF-1 in the general group and more than 90% of the variance of its level in groups of patients with nodular goiter with high IGF-1 with / without obesity. In patients with nodular goiter with high IGF-1 and obesity, the predictor of increased thyroid volume is BRI, which explains 81.14% of the variance of its volume.
 Conclusions: Patients with nodular goiter with IGF-1 level in blood above the sex-age norm have significantly higher values ​​of anthropometric indicators IR (WHtR, ABSI, BFD and BAI) compared with patients with a normal level of this indicator; in patients with nodular goiter with II degree obesity and above, thyroid volume is significantly associated with BMI; BAI (R2 = 82.37%) is a predictor of increased levels of IGF-1 in blood of patients with nodular goiter, regardless of the obesity; BRI (R2 = 81.14%) is a predictor of increased thyroid volume in patients with nodular goiter with IGF -1 high level and obesity.
 Key words: nodular goiter, anthropometric indicators, insulin resistance