Risk Factors for Clinically Overt Hypothyroidism in Unselected Population of Adult Epilepsy Patients

Objective:This study aimed to investigate the risk factors for hypothyroidism in patients with adult epilepsy patients.Methods:Hospital charts of 530 patients were reviewed retrospectively. Patients with a definite diagnosis of hypothyroidism with persistent adherence to antiseizure medications (ASM) were included. An age and gender-matched group of 110 patients was selected as the control group.Results:The rate of hypothyroidism was significantly higher in patients with epilepsy (p=0.01). The patients with epilepsy were separated into two groups-the patients with and without hypothyroidism. The distribution of other neurologic disorders was similar in epilepsy patients with and without hypothyroidism (p=0.46). The comparison of the two groups showed that, independent of the ASM type, receiving any polytherapy regimen was a significant risk factor for hypothyroidism (p=0.02) and epilepsy patients with hypothyroidism had a longer duration of epilepsy (p=0.03). Logistic regression analysis revealed that the only independent risk factor for hypothyroidism was being on a polytherapy regimen (p=0.02).Conclusion:In this study, we found two major results: i) compared with an age and gender-matched control group, epilepsy is a major risk factor for hypothyroidism, ii) independent of the ASM type, receiving a polytherapy regimen is a predictive risk factor for hypothyroidism.