Subclinical hypothyroidism and anti-thyroid peroxidase antibodies in primary open-angle glaucoma: A case–control study

Abstract

Purpose: To evaluate the association among subclinical hypothyroidism, anti-thyroid peroxidase (anti-TPO) antibody, and primary open-angle glaucoma (POAG). Study design: Case–control study. Methods: The cases consisted of patients with POAG and controls were age- and sex-matched patients from the general eye clinic with no history of glaucoma. Blood samples were taken from the participants’ antecubital veins and sent for measurement of thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), and anti-thyroid peroxidase (anti-TPO) antibody. Data was analyzed using the Mann–Whitney U test and the Chi-square test. Odds ratio with 95% confidence interval (CI) was calculated. A two-tailed P value less than 0.05 was considered for statistical significance. Results: There were a total of 63 cases and 63 controls. Subclinical hypothyroidism was present in 20.6% of patients in the glaucoma group and 4.8% of patients in the control group (P < 0.01). The odds of subclinical hypothyroidism in patients with POAG compared to controls was 5.2 (95% CI 1.7–22). Anti-TPO antibody positivity was higher in the glaucoma group (22.2%) than in the control group (14.3%), but this did not reach statistical significance (P = 0.25). Conclusion: This study suggests an association between POAG and subclinical hypothyroidism. Further research is needed to establish the cause-and-effect relationship between these two conditions.