The Characteristic Of Lipid Profile And LDL And HDL Subfraction In Newly Diagnosed Hypothyroidism

Hypothyroidism is a common thyroid disease.It can result in lipid metabolism disorders,hypothyroidism and its associated abnormalities of the blood lipid spectrum was considered to be the risk factors of atherosclerosis and coronary heart disease.The elevated small and dense LDL(SdLDL),triglyceride(TG) and lower high-density lipoprotein cholesterol(HDL-C) are known as "triple lipid disorders," and are more accurate reflection of atherogenic Lipid spectrum.The changes of blood lipid spectrum caused by hypothyroidism were reported inconsistencies, the effect of hypothyroidism on HDL-C and small and dense LDL have few reported in the existing literature.So to investigated changes of blood lipid spectrum,HDL-C and sdLDL in patients with hypothyroidism is of great significance to understand whether the changes is more atherogenic, and of great significance to understand the relationship between hypothyroidism and coronary heart disease.Comparing the new diagnosis of hypothyroidism in patients with 160 cases,of which sub-clinical hypothyroidism group 81 cases(average age 53.63±15.83),clinical hypothyroidism group 79 cases(average age 46.25±16.55),with 60 Normal people(average age of 53.73±7.94),the spectrum of blood lipids and LDL subfraction were analysis.The results showed that the cases of abnormal blood lipid in sub-clinical hypothyroidism group and clinical hypothyroidism group were 51 cases and 50 cases,the rate was 63 percent and 63.3 percent,in accordance with China's proposal of the judgement.Disorders of cholesterol, triglycerides and low-density lipoprotein cholesterol are the main performance.In the normal group,sub-clinical hypothyroidism group, clinical hypothyroidism Group,TC were 4.70±0.85,5.32±1.27,5.72±1.45(mmol·L-1),TG were 1.28±0.54,1.75±1.06,1.73±1.21 (mmol·L-1),HDL-C were 1.59±0.57,1.54±0.42,1.69±0.70(mmol·L-1),LDL-C were 2.60±0.82,3.00±1.02,3.26±1.18(mmol·L-1), LDL diameter were 27.60±0.95,25.96±0.91,26.04±1.08(nm).TC, TG and LDL-C in Subclinical hypothyroidism group and hypothyroidism group were higher than normal(P＜0.05),the diameter of LDL is less than normal (P＜0.05),HDL-C change was not significant.Both TC and LDL-C were related to FT3,FT4 and logTSH.TC and LDL-C were negatively correlated with FT3, FT4 and positively correlated with logTSH;HDL-C was positively correlated with IogTSH;TG was negatively correlated with FT3,FT4. Diameter of LDL particles was positively correlated with HDL-C,and negatively correlated with BMI,blood pressure,fasting glucose,TC,TG. At the same time,separation of lipoprotein by fast protein liquid chromatography(FPLC) also show that patients with hypothyroidism VLDL-TG, LDL-TG were higher than the control,and HDL particle size was different from the control,HDL particles shift toward the large HDL particles sizes, in another word,HDL subclass has changed.In summary,TC,TG,LDL-C in hypothyroidism group were higher than normal,diameter of LDL particles was lower,HDL-C change was not significant difference,but HDL particles shift to the large HDL particles, in another word,HDL subclass has changed.The elevated small and dense LDL(SdLDL),triglyceride(TG) and lower high-density lipoprotein cholesterol(HDL-C) are known as "triple lipid disorders," and are more accurate reflection of atherogenic Lipid spectrum.The elevated level of TG,SdLDL and changed HDL subclass show that the blood lipid spectrum,change to that of more atherogenic in hypothyroidism group.