Carotid Intima Media Thickness in Graves Disease: Comparing Overt Hyperthyroid and Remission State

Abstract

Background/Objective: Hyperthyroid has been associated with increased cardiovascular event. Carotidintima media thickness (CIMT) is oftenly measured to evaluate the risk of cardiovascularevent. The aim of this study is to measure CIMT in Graves’ disease and to comparebetween subjects in overt hyperthyroidism and remission state. Methods: Our study was a cross-sectional study performed at the outpatient endocrinologyclinic of Dr. Cipto Mangunkusumo Hospital, a tertiary care hospital in Jakarta, Indonesia. Graves’ disease subjects were recruited, of whom then grouped into overthyperthyroidism (clinical signs and symptoms of hyperthyroidism, low THS, highthyroxine levels, treatment naïve of within 3 months of treatments) and remission state(no clinical signs and symptoms of hyperthyroidism, normal THs and thyroxine levels,without any anti thyroid drugs for at least 6 months). CIMT measurements wereperformed by trained physician on both right and left artery carotid arteries using anultrasound equipped with software that automatically measured the CIMT. We alsomeasured lipid profile, fasting blood glucose, and ECG. Results: We recruited 49 Graves’ disease subjects, of whom 32 and 17 subjects werein overt hyperthyroidism and remission state respectively. Median CIMT in overthyperthyroidism and remission state were 0,473 mm and 0,488 mm respectively, p:0,109. Among clinical and laboratory risk factors, only age which had an independentcorrelation with CIMT in Graves disease. (r: 0,371; p:<0,0001). Discussion: Our is the first study that measured CIMT among subjects with Graves’disease in remission and overt hyperthyroidism state, of which we observed nodifferences. This might be due to the fact that the atherosclerosis risk factors were notdistributed evenly on both group, of which subjects were older in the remission group. Ithas been reported that there are increasing CIMT along with aging (0,003-0,010 mm peryear). Furthermore, in remission state we need to take metabolic and physical changesinto consideration, such as increasing weight as much as 2,5% from prior weight alongwith increasing total cholesterol and LDL-cholesterol which both can affect CIMT levels. Conclusions:There are no significant differences in CIMT between overt hyperthyroid andremission state in Graves’ disease. Keywords: carotid intima media thickness, Graves’ disease, overt hyperthyroid, remission.