Hypothyroidism in Metabolic Syndrome

Background: Metabolic syndrome (Syndrome X/Insulin resistance syndrome) consists of central obesity, hypertriglyceridemia, low high-density lipoprotein (HDL) cholesterol, hyperglycemia and hypertension as its major features. All of them can be influenced by the  functioning of a 20 g endocrine organ, the thyroid gland. Aims and objectives: To study the proposed association between metabolic  syndrome and thyroid dysfunction. Material and methods: Hundred subjects aged more than 18 years, willing to participate in the study  and fulfilling criteria of the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) for diagnosis of metabolicsyndrome were included. Detailed clinical examination and laboratory investigations of all subjects were done. Risk factors were  identified and analyzed by comparing the subjects with and without thyroid dysfunction. Results: Eighty-one out of 100 subjects with metabolic syndrome belonged to the age group between 41 and 70 years. Females comprised 60% of the total patient population with sedentary lifestyle as the major risk factor, whereas males comprising rest of the 40% had addictive behaviors as major risk factors. Observation of individual parameters under NCEP-ATP III showed that 57 patients fulfilled all 5 criteria, 34 patients fulfilled 4 and 9 patients fulfilled 3 criteria. Obesity and dyslipidemia were common among female subjects, whereas impaired glucose tolerance andhypertension were common among males. Thyroid dysfunction in the form of hypothyroidism was present in 30 subjects with females (23 patients) being the statistically significant population (p < 0.0001). Hypothyroidism was of subclinical type in 21 of these 30 subjects. None had hyperthyroidism. Left ventricular ejection fraction (mean ± SD) was lowered to 42.67 ± 6.53 from 49.07 ± 7.48 in presence of thyroid dysfunction in these subjects with metabolic syndrome (p < 0.0001). Conclusion: Metabolic syndrome and hypothyroidism (even subclinical) are both individual as well as combined risk factors for development of atherogenic dyslipidemia, diabetes mellitus and cardiovascular disease with elderly females comprising the high risk group