Subclinical Hypothyroidism: A Modifiable Risk Factor for Retinal Vein Occlusion

Abstract

Introduction: It is well established that overt hypothyroidism, itself was a risk factor for atherosclerosis. Retinal Venous Occlusion (RVO) is caused by localised atherosclerosis. Subclinical Hypothyroidism (SCH) also cause arteriosclerosis thereby could be an important causative factor for RVO. But no study on SCH in RVO has taken place in Indian population. Aim: To find the prevalence of SCH in RVO in Indian Population. Materials and Methods: Thyroid hormones and Anti-Tissue Peroxidise (TPO) antibody was measured in 479 RVO cases in this two year prospective cross-sectional study in ESIC medical college. Data was entered into Microsoft Excel and presented in tables. Results: In this study, 312 males (aged 52±7.2 years) and 167 females (aged 47±7.7 years) with RVO were screened for thyroid hormones and anti-TPO antibody. Thyroid disorders were found in 162 patients out of 479 participants in this study (33.8%). Moreover, 52 cases were found to have SCH (10.8%) which is 32.1% of total thyroid disorder among RVO cases. Total of 118 patients had high anti-TPO antibody among 162 RVO cases with thyroid disorders (72.8%) and only 67 had high anti-TPO antibody among 317 euthyroid RVO cases (21.1%). Conclusion: This study has shown that SCH was a modifiable risk factor of RVO. Therefore, understanding the prevalence of SCH in this population might help in the prevention of RVO by secondary preventive intervention. Moreover, all SCH cases should be referred to ophthalmologist for evaluation of retinal vasculature.

Keywords

• retinal venous occlusion
• subclinical hypothyroidism
• thyroid peroxidase antibody