OBJECTIVE: To evaluate weight change during hyperthyroidism treatment, and to correlate it with IL-6 and TNF-alpha concentrations. SUBJECTS AND METHODS: Forty two patients were included. Body weight (BW), body mass index (BMI), clinical and laboratory characteristics were recorded. IL-6 and TNF-alpha were determined before treatment with methimazole (MMI) and in euthyroidism. RESULTS: BW was 59.62 ± 11.5 kg in hyperthyroidism, and 69.91 ± 14.4 kg in euthyroidism (p < 0.001). BMI increased from 23.1 ± 3.8 kg/m² to 27 kg/m² ± 4.7 during treatment (p < 0.0001). Before treatment, 66.6% subjects had BMI < 25 kg/m² and 33.3%, BMI > 25 kg/m². In euthyroidism, 38% of patients had BMI < 25 kg/m² and 62%, BMI > 25 kg/m² (p = 0.01). In euthyroidism, we found a significant reduction in IL-6 and TNF-alpha concentrations, but no correlation between IL-6 and TNF-alpha, and BW or BMI. CONCLUSION: An important increase in BW and BMI was observed during hyperthyroidism treatment, and IL-6 and TNF-alpha alterations were only related with return to euthyroidism.
Hyperthyroidism; tumour necrosis factor alpha; interleukin-6; methimazole; thyroid hormone; body weight