The Effect of Levothyroxine on Arterial Stiffness and Lipid Profile in Patients
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 34
研究概览
简要总结
We evaluated the effect of levothyroxine in subclinical hypothyroidism (SCH) on arterial stiffness, lipid profile and inflammation. Thirty-four patients with SCH were included. Patients were treated with levothyroxine for 7 months. Arterial stiffness was evaluated by Augmentation index (AIx). After accomplishing euthyroidism, the AIx decreased from 8.3±17.2 to 6.5±14.3(P<0.01) and AIx percentage decreased from36.2 11.5 ± to 9.1±33.2 (P =0.03). Systolic blood pressure decreased from 20±134.7 to mmHg 13.7±127.6 (P<0.01). No significant improvement was found in other parameters. In patients whose AIx's decreased, LDL-cholesterol levels decreased by 37.1±-15.5 mg/dl compared to the patients whose AIx's didn't decrease and LDL-cholesterol increased by 57.4±24.1 mg/dl (P=0.057). We concluded that in patients suffering from SCH, treatment with levothyroxine had a significant beneficial effect on arterial stiffness and systolic blood pressure and no effect on lipid profile or inflammation.
详细描述
Subclinical hypothyroidism (SCH) is a disorder characterized by high levels of thyrotropin (thyroid stimulating hormone (TSH)), accompanied by normal levels of thyroxine (T4). There is most probably an association between SCH and cardiovascular disease, however the relationship between SCH and cardiovascular morbidity and mortality is still in debate.
Hak et al. and Walsh et al. found that patients with SCH have increased risk for ischemic heart disease. Female smokers over 50 years, with TSH levels above 10 mU/L, were at a higher risk. However, a study conducted by Rodondi et al. did not find that SCH increases the risk for cardiac ischemia, peripheral vascular disease or cerebrovascular disease.
Among the risk factors for atherosclerosis in patients with SCH are hypertention, atherogenic lipid profile, high levels of c-reactive protein (CRP), changes in the clotting system, endothelial dysfunction and increased arterial stiffness.
Studies have shown that patients with SCH suffer from increased arterial stiffness and endothelial dysfunction. One of the non invasive techniques to evaluate arterial stiffness is pulse wave analysis (PWA). PWA gives information of blood pressure at the aortic site rather than more peripherally. Recently, calculated AIx was suggested as an independent risk marker for cardiovascular adverse events. Obuobie et al. analyzed the pressure wave velocity in 12 patients with overt hypothyroidism treated with levothyroxine. They concluded that hypothyroid patients treated with levothyroxine had a decrease in their arterial stiffness after treatment, although no difference in the lipid profile was found.
Taddei et al. showed that patients with SCH are characterized by endothelial dysfunction resulting from a reduction in nitric oxide (NO); this alteration was partially independent of dyslipidemia and reversed by levothyroxine treatment.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Laboratory evidence of subclinical hypothyroidism (TSH levels 4-25 mU/L and normal T4 values) in at least two following tests (one month apart from each other)
排除标准
- •Recent (less than 6 months) myocardial infarction, cerebrovascular event or angiography with stent placement
- •Serious infection in the month before recruitment
- •Any use of contrast media in the last 6 months
- •Loss of more than 5% of body weight during the last 6 months
- •Cardiac arrhythmias
- •Ejection fraction of less than 40%
- •Active malignant diseases
- •Previous thyroid disease and
- •Pregnancy.