Meng Zhao1,2,3, Lu Liu1,2,3, Fei Wang4, Zhongshang Yuan5, Xu Zhang1,2,3, Chao Xu1,2,3, Yongfeng Song1,2,3, Qingbo Guan1,2,3, Ling Gao2,3,6, Zhongyan Shan7, Haiqing Zhang1,2,3, Jiajun Zhao1,2,3. 1. 1 Department of Endocrinology, Shandong Provincial Hospital affiliated to Shandong University , Jinan, China . 2. 2 Shandong Clinical Medical Center of Endocrinology and Metabolism , Jinan, China . 3. 3 Institute of Endocrinology and Metabolism , Shandong Academy of Clinical Medicine, Jinan, China . 4. 4 School of Clinical Medicine, Ningxia Medical University , Yinchuan, China . 5. 5 Department of Epidemiology and Biostatistics, School of Public Health, Shandong University , Jinan, China . 6. 6 Scientific Center, Shandong Provincial Hospital affiliated to Shandong University , Jinan, China . 7. 7 Department of Endocrinology and Metabolism, The First Affiliated Hospital of China Medical University , Shenyang, China .
Abstract
BACKGROUND:Mild subclinical hypothyroidism (SCH) affects a large number of people and is known to be a risk factor for dyslipidemia. However, whether mild SCH patients should be treated with L-thyroxine to improve lipid profiles remains controversial. In addition, it is also unclear whether all mild SCH patients can benefit from L-thyroxine treatment, regardless of basal thyrotropin or lipid levels. This study aimed to assess the effects of L-thyroxine replacement therapy on the lipid profiles of mild SCH patients. METHODS: This open-label randomized controlled trial was performed in Ningyang County, Shandong Province, China. A total of 378 mild SCH patients with diagnoses confirmed by two thyroid function tests were randomly assigned to either the intervention group (L-thyroxine replacement therapy) or the control group (no treatment). The primary outcome was a change in serum total cholesterol (TC) concentration. RESULTS: In all, 369 participants completed the 15-month follow-up period. Reduced TC concentrations were more prominent in the intervention group than they were in the control group (-0.41 mmol/L vs. -0.17 mmol/L; p = 0.012), and changes in low-density lipoprotein cholesterol levels exhibited the same trend. Subgroup analyses were performed to assess the effects of L-thyroxine in patients with different thyrotropin or TC levels. When the study population was stratified according to basal thyrotropin concentration, all patients who had received L-thyroxine showed reduced TC levels (p < 0.001). The treatment was similarly beneficial for all patients, regardless of basal TC level. Even for subjects with TC levels <5.18 mmol/L, serum TC concentrations remained unchanged in the intervention group (p = 0.936) but increased by 0.35 mmol/L in the control group (p = 0.004). CONCLUSIONS: The findings suggest that mild SCH patients could benefit from L-thyroxine treatment to improve lipid profiles, regardless of basal thyrotropin or TC concentrations.
RCT Entities:
BACKGROUND: Mild subclinical hypothyroidism (SCH) affects a large number of people and is known to be a risk factor for dyslipidemia. However, whether mild SCH patients should be treated with L-thyroxine to improve lipid profiles remains controversial. In addition, it is also unclear whether all mild SCH patients can benefit from L-thyroxine treatment, regardless of basal thyrotropin or lipid levels. This study aimed to assess the effects of L-thyroxine replacement therapy on the lipid profiles of mild SCH patients. METHODS: This open-label randomized controlled trial was performed in Ningyang County, Shandong Province, China. A total of 378 mild SCH patients with diagnoses confirmed by two thyroid function tests were randomly assigned to either the intervention group (L-thyroxine replacement therapy) or the control group (no treatment). The primary outcome was a change in serum total cholesterol (TC) concentration. RESULTS: In all, 369 participants completed the 15-month follow-up period. Reduced TC concentrations were more prominent in the intervention group than they were in the control group (-0.41 mmol/L vs. -0.17 mmol/L; p = 0.012), and changes in low-density lipoprotein cholesterol levels exhibited the same trend. Subgroup analyses were performed to assess the effects of L-thyroxine in patients with different thyrotropin or TC levels. When the study population was stratified according to basal thyrotropin concentration, all patients who had received L-thyroxine showed reduced TC levels (p < 0.001). The treatment was similarly beneficial for all patients, regardless of basal TC level. Even for subjects with TC levels <5.18 mmol/L, serum TC concentrations remained unchanged in the intervention group (p = 0.936) but increased by 0.35 mmol/L in the control group (p = 0.004). CONCLUSIONS: The findings suggest that mild SCH patients could benefit from L-thyroxine treatment to improve lipid profiles, regardless of basal thyrotropin or TC concentrations.
Authors: Martin Feller; Marieke Snel; Elisavet Moutzouri; Douglas C Bauer; Maria de Montmollin; Drahomir Aujesky; Ian Ford; Jacobijn Gussekloo; Patricia M Kearney; Simon Mooijaart; Terry Quinn; David Stott; Rudi Westendorp; Nicolas Rodondi; Olaf M Dekkers Journal: JAMA Date: 2018-10-02 Impact factor: 56.272
Authors: Richard Birtwhistle; Kate Morissette; James A Dickinson; Donna L Reynolds; Marc T Avey; Francesca Reyes Domingo; Rachel Rodin; Brett D Thombs Journal: CMAJ Date: 2019-11-18 Impact factor: 8.262