Abstract:
Objective: Subclinical hypothyroidism (SCH) has been identified as a risk for atherosclerosis
and Coronary Artery Disease (CAD). The aim of this study was to determine the prevalence and
association between hypothyroidism or subclinical hypothyroidism (SCH) and lipid parameters,
anthropometric data and the severity of coronary artery disease (CAD) in patients awaiting Coronary
Artery Bypass Graft Surgery (CABG) from a selected center. Method: A cross sectional analytical
study was carried out amony patients awaiting CABG in a selected center. Thyroid profile (enzyme
immunoassay method), lipoprotein (a) [Lp(a)], C- reactive protein (CRP) (immunoturbidimetric
method) were determined and the Gensini score calculated. Lipid parameters and details of current
medication were obtained from the medical records and anthropometric data were measured.
Results: From a total of 102 patients 3% were on treatment for hypothyroidism and 15% had
subclinical hypothyroidism. A significantly high (p= 0.04) percentage of SCH patients (75%) were
dyslipidemic. There were no significant differences observed in lipid profiles and Lp(a) among SCH
and euthyroid patients when the total sample or dyslipidemic sample was considered. However,
a significantly high percentage (58%, p<0.05) of SCH patients on statins had a higher level of low
density lipoprotein cholesterol (LDLc) compared to euthyroid dyslipidemic patients. A significant
negative (p< 0.05) correlation was observed between thyroid stimulating hormone concentration
and high density lipoprotein cholesterol (r= -0.67) in SCH group. No significant differences were
observed in anthropometric data, CRP or Gensini score of SCH and euthyroid patients with CAD.
Conclusion: The prevalence of dyslipidemia among SCH patients with CAD was significantly high.
The patients suffering from SCH exhibited higher levels of LDLc compared to euthyroid patients
from both the total and dyslipidemic groups. SCH patients under statin treatment displayed a higher
LDLc suggesting a strong association between coronary artery disease and thyroid disease.
