Lipoprotein (A), Apolipoprotein A1 and B Levels in Subclinical Hypothyroid Patients and Healthy Persons

Background: Lipoprotein (a) (LP(a)) is an independent risk factor for coronary artery disease and atherosclerosis this lipoprotein is elevated in hypothyroidism. Abnormality in LP (a) synthesis occurs in thyroid hormone disorders. There are a few reports on the direct relationship between Apo B and arterial stiffness. Subclinical hypothyroid patients had significantly higher levels of Apo B, while levels of ApoA1 did not differ significantly.Aim: The aim of this study was to investigate the status of Lipoprotein (a),Apolipoprotein A1 and B levels in subclinical hypothyroid patients and compared with healthy persons. Methods and material: 40womenwith subclinical hypothyroid and between the age group of 20 to 60 years whome referred to Sayyad-Shirazi Hospital in Gorgan,in northern Iran were recruited in present study (mean age, 58±7 years, mean body mass index, 21.8±3 kg/m2) in addition to 40 healthy control women and were matched based on age and BMI.Serum Lipoprotein (a), Apolipoprotein A1 and B levels were measured in both group's case and control. Results: By comparison of the clinical characteristics of 40 cases of subclinical hyperthyroidism and 40 age- and BMI-matched healthy controls, HDL-C was significantly decreased in SCH group than controls (p = 0.013).SBP, DBP, Apo-A1, Apo-B and LP-(a)did not show any significant difference between the two groups. Conclusions: The result of this study showed significant difference in regard to HDL-C between cases and controls. Thyroid stimulating hormone(TSH)and triglyceride(TG)were significantly higher in subclinical hypothyroid patients group in comparison to healthy group. There were significant correlations between Apo-A1 and   freeT4 , T3 , Apo-B and LP (a) in both groups. Apo-B was related significantly with freeT4 and T4 in cases alone and with LP (a) in both cases and controls. The relationships between LP (a) freeT4 and T4 were significant and reverse in  subclinical hypothyroidism(SCH )group lonely.