Hypothyroidism in acute coronary syndrome – A prospective Indian study

Background: Evidence suggests that hypothyroidism may be associated with an increased risk of acute coronary syndrome (ACS).The data regarding the influence of hypothyroidism on cardiovascular disease in the Asian population is conflicting. Therefore, we undertook this study to assess the overall prevalence of hypothyroidism in Acute Coronary Syndrome (ACS) patients and determine if there is a relationship between hypothyroidism, both sub-clinical and overt and other significant risk factors of ACS in an Indian population. Methods: We studied 487 hospitalized patients between March 2018 and February 2021 with a diagnosis of ACS to determine the prevalence of hypothyroidism, both clinical and sub-clinical and their relationship with other known coronary risk factors. Thyroid function Tests - free T3, free T4 and TSH were collected from all the patients within 24 h of their admission to the coronary care unit (CCU) of 2 major hospitals in New Delhi and Imphal (Manipur). Results: Subclinical hypothyroidism was prevalent in 44 (9 %), followed by overt hypothyroidism in 25 (5.2 %).Subclinical hypothyroidism was more common in females, whereas overt hypothyroidism was more common in males. ST Elevation Myocardial Infarction (STEMI) (52 %), followed by Non-ST-Elevation Myocardial Infarction (NSTEMI) (25 %), was the commonest diagnosis at presentation. Patients with overt hypothyroidism showed a higher proportion of increased triglyceride levels.Patients with hypothyroidism had no differences in the prevalence of concomitant diabetes hypertension and other coronary risk factors. Conclusions: Patients with ACS without known thyroid disorders should be screened for hypothyroidism since it is found frequently. There might be a case to treat their thyroid dysfunction appropriately.