Lipid Profile in Thyroid Autoimmunity - A Study among Reproductive Age Group Females of Central Kerala

Abstract

BACKGROUND One of the most common causes of thyroid dysfunction among women is autoimmunity, especially in fertile age group. Thyroid hormone disorders are associated with a number of biochemical abnormalities including dyslipidaemia, metabolic dysfunctions, spontaneous miscarriage, and preterm delivery. Dyslipidaemia is one of the most common metabolic abnormalities present in patients with thyroid disease. The purpose of this study was to find the association between anti-thyroid peroxidase antibody (anti-TPO) and dyslipidaemia in reproductive age group females from Central Kerala. METHODS A total of 200 asymptomatic women, all in reproductive age group, from a tertiary hospital in Kerala participated in this study. Demographic data and detailed medical history of the participants were collected. Anti-TPO and thyroid stimulating hormone (TSH) were measured using chemiluminescence immunoassay system. Serum lipid profile was estimated using fully automated random-access clinical chemistry analyser EM - 360. Continuous variables were compared between the groups using Mann–Whitney U-test. P value lesser than 0.05 was considered as statistically significant. RESULTS The mean age of the subjects was 32.92 ± 11.82 years. A total of 47 participants (23.5 %) were anti-TPO positive. Abnormality in lipid profile was present in 72.34 % (N = 34) of the anti-TPO positive participants. In the anti-TPO positive group, 51.06 % of the participants had hypercholesterolemia. In the anti-TPO positive group, anti-TPO levels show a statistically significant correlation with total cholesterol and triglyceride levels (P = 0.07 and P < 0.01). A total of 9 % (N = 18) had thyroid stimulating hormone (TSH) values greater than normal range (0.34- 4.25 µIU/mL) suggesting presence of hypothyroidism. TSH values were also significantly associated with lipid profile in the anti-TPO positive group. Both thyroid autoimmunity and dyslipidaemia can affect fertility, pregnancy and other reproductive outcomes. CONCLUSIONS Women should be screened for autoimmune antibodies and associated biochemical abnormalities to estimate and reduce the risk of cardiovascular morbidity, negative pregnancy outcomes and infertility. KEY WORDS Thyroid Autoimmunity, Anti-TPO Antibody, Dyslipidaemia