Hypothyroidism in Metabolic Syndrome

Abstract

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 metabolic syndrome 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 and hypertension 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.