PSUN47 Increased Prevalence of Metabolic Syndrome Among Adult Filipinos with Hypothyroidism

Abstract

Abstract Dyslipidemia in patients with hypothyroidism results from effects of thyroid hormones on lipid metabolism. Hypothyroidism is characterized by a state of attenuated basal plasma insulin, high insulin resistance and hypothyroidism-induced hemodynamic alterations. All of which are risk factors for the development of metabolic and cardiovascular diseases. In this study, we determined the prevalence of metabolic syndrome among adult Filipinos with hypothyroidism and compared clinical and laboratory characteristics of those with versus without metabolic syndrome. We also compared and validated the results of body mass index as a surrogate marker versus waist circumference in the diagnosis of metabolic syndrome. We conducted a prospective study of 120 Filipino adults with hypothyroidism. Anthropometric and blood pressure measurements were performed followed by blood extraction for fasting plasma glucose, lipid profile, thyroid stimulating hormone, free thyroxine levels, free triiodothyronine levels and anti-thyroid peroxidase antibody levels. The presence of metabolic syndrome was determined using WHO criteria and race-specific cut-offs for waist circumference. Both clinical and laboratory characteristics were compared between those with and those without metabolic syndrome. Significant differences were determined by two-way ANOVA while heterogeneity of categorical variables was determined by chi-square or Fisher exact test. Use of BMI as surrogate marker was estimated by Pearson's correlation coefficient and kappa statistic. All data analyses were performed using Stata version 17.1 with a level of significance at p<0.05. The overall prevalence of metabolic syndrome was 40.00% (95%CI: 31.17%–49.34%). The male to female ratio was 1: 2 (41: 79 patients) and primary hypothyroidism comprised 88.89% (n = 109) of the cohort. Patients with metabolic syndrome have a significantly higher mean waist circumference (females: 89.73 ± 7.50 cm vs. 80.13 ± 10.13 cm; males: 93.16 ± 10.25 cm vs. 83.52 ± 8.25; p<0.001), higher proportion with diabetes (22.92% vs. 1.39%; p<0.001) and hypertension (45.83% vs. 8.33%; p<0.001) compared to those without. Furthermore, metabolic syndrome patients have significantly higher median free thyroxine levels at 11.59 (13.41) pmol/L; p=0.043). Waist circumference and body mass index are highly directly correlated (r2=0.7471) but showed only weak agreement (K=0.4970). The use of body mass index in place of waist circumference had a high diagnostic accuracy of 93.80% for metabolic syndrome (6 patients were missed using body mass index). There were no significant differences in terms of age, sex, etiology of hypothyroidism, blood pressure levels, fasting plasma glucose, lipid profile, thyroid stimulating hormone levels, free triiodothyronine, and anti-thyroid peroxidase autoantibody levels between patients with and without metabolic syndrome. Our study showed that the prevalence of metabolic syndrome in adult Filipinos with hypothyroidism is increased at 40% compared to general euthyroid population. The most important drivers of metabolic syndrome identified were increased waist circumference, high body mass index, and the presence of hypertension and diabetes mellitus. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.