Lean body mass is a major determinant of levothyroxine dosage in the treatment of thyroid diseases

被引：158

作者：

Santini, F ^{[1
]}

Pinchera, A ^{[1
]}

Marsili, A ^{[1
]}

Ceccarini, G ^{[1
]}

Castagna, MG ^{[1
]}

Valeriano, R ^{[1
]}

Giannetti, M ^{[1
]}

Taddei, D ^{[1
]}

Centoni, R ^{[1
]}

Scartabelli, G ^{[1
]}

Rago, T ^{[1
]}

Mammoli, C ^{[1
]}

Elisei, R ^{[1
]}

Vitti, P ^{[1
]}

机构：

[1] Univ Pisa, Dept Endocrinol, I-56124 Pisa, Italy

来源：

JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM | 2005年 / 90卷 / 01期

关键词：

D O I：

10.1210/jc.2004-1306

中图分类号：

R5 [内科学];

学科分类号：

1002 ; 100201 ;

摘要：

Total body weight is usually employed to calculate the amount of L-T(4) to be administered in patients with thyroid diseases. The aim of this study was to evaluate the effect of body composition on L-T(4) requirements. Body composition was assessed by dual energy x-ray absorptiometry in 75 patients on TSH-suppressive L-T(4) therapy after conventional thyroid ablation for differentiated cancer. The mean daily dose of L-T(4) was lower in normal-weight (127.5 +/- 21.3 mug/d) vs. overweight (139.4 +/- 24.5) and obese (151.3 +/- 29.1) subjects. There was a much stronger association between the L-T(4) dosage and lean body mass (P < 0.001, r =0.667) compared with fat mass (P = 0.023, r = .26). Measurement of regional tissue composition showed peripheral lean mass as the best correlate with the dose of L-T(4) (r =0.679, P < 0.001) whereas no correlation was observed with peripheral fat mass. In conclusion, individual L-T(4) requirements are dependent on lean body mass. Age- and gender-related differences in L-T(4) needs reflect different proportions of lean mass over the total body weight. An estimate of lean mass may be helpful to shorten the time required to attain a stable dose of L-T(4), particularly in subjects with high body mass index values that may be due either to increased muscular mass or to obesity.

引用

页码：124 / 127

页数：4

共 32 条

[1] Timing and magnitude of increases in levothyroxine requirements during pregnancy in women with hypothyroidism [J].