Open AccessThe effect of L‐thyroxine substitution on lipid profile, glucose homeostasis, inflammation and coagulation in patients with subclinical hypothyroidism
Author(s) -
Anagnostis P.,
Efstathiadou Z. A.,
Slavakis A.,
Selalmatzidou D.,
Poulasouchidou M.,
Katergari S.,
Karathanasi E.,
Dogramatzi F.,
Kita M.
Publication year - 2014
Publication title -
international journal of clinical practice
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.756
H-Index - 98
eISSN - 1742-1241
pISSN - 1368-5031
DOI - 10.1111/ijcp.12394
Subject(s) - medicine , endocrinology , insulin resistance , fibrinogen , homocysteine , apolipoprotein b , glucose homeostasis , insulin , apolipoprotein a1 , c reactive protein , cholesterol , high density lipoprotein , lipid profile , inflammation
Summary Aims Subclinical hypothyroidism ( SH ) is associated with increased risk for atherosclerosis, mainly attributable to dyslipidaemia and hypercoagulability. However, conflicting data exist regarding the effect of L‐thyroxine substitution on these parameters. The purpose of this study was to assess the effect of L‐thyroxine therapy on lipidaemic profile, coagulation markers, high‐sensitivity C‐reactive protein (hs CRP ) and glucose homoeostasis in SH patients. Methods It was a prospective open‐label study. The following parameters were measured before and 6 months after intervention: anthropometric data, total cholesterol ( TC ), low‐density lipoprotein cholesterol ( LDL ‐C), high‐density lipoprotein cholesterol ( HDL ‐C), triglycerides ( TG ), apolipoproteins B (apoB) and A1 (apoA1), lipoprotein (a) [Lp(a)], fasting plasma glucose and insulin, homoeostasis model assessment‐insulin resistance ( HOMA ‐ IR ), hs CRP , antithrombin III ( AT ‐ III ), protein C ( PC ), protein S ( PS ), fibrinogen and homocysteine. Results Thirty‐two patients (30 women) aged 52.1 ± 13.9 years with SH completed the study. Baseline mean TSH levels were 6.79 ± 2.58 mIU /ml. Achievement of euthyroidism significantly reduced systolic blood pressure (BP) in patients with SH (from 135.2 ± 18.5 to 129.7 ± 15.8 mmHg, p = 0.03) and diastolic BP only in those with baseline TSH levels > 7 mIU /ml (from 79.5 ± 9.8 to 72.1 ± 7.3 mmHg, p = 0.03). No significant changes in body weight, TC , LDL ‐C, HDL ‐C, TG , apoB, glucose, insulin, HOMA ‐ IR , hs CRP , AT ‐ III , PC , PS , fibrinogen or homocysteine levels were noticed after restoration of euthyroidism, except for a decrease in apoA1 (p = 0.04) and an increase in Lp(a) levels (p = 0.02). Conclusions Except for a reduction in systolic and diastolic BP , thyroid substitution therapy does not affect lipidaemic profile, systematic inflammation, glucose homoeostasis or coagulation in patients with SH .