Early Risk Stratification of Thyroid Eye Disease in Newly Diagnosed Graves' Disease

The aim of this observational study is to investigate why some people with newly diagnosed Graves' disease (GD) develop thyroid eye disease (TED), also known as Graves' orbitopathy, while others do not. The main questions the study aims to answer are: 1. What proportion of participants develop TED within one year of being diagnosed with GD? 2. Which early clinical signs, ophthalmological findings, blood biomarkers, tear-fluid biomarkers, or ocular surface microbiome characteristics are associated with an increased risk of developing thyroid eye disease? Participants with newly diagnosed GD will attend two study visits, one at baseline and one approximately one year later. At each visit, participants will: * Answer questions about their symptoms and quality of life * Undergo a standardized eye examination and have clinical photographs taken of their eyes * Provide blood samples, tear-fluid samples, and a small swab sample from the ocular surface The study will also include healthy volunteers and participants with moderate-to-severe TED. Participants in these comparison groups will attend one study visit. Researchers will compare findings across the groups to better understand the early clinical and biological changes associated with thyroid eye disease. The long-term aim is to improve the early detection and follow-up of people with GD who may be at increased risk of developing TED.

Inclusion Criteria: Newly Diagnosed Graves' Disease (GD) Cohort: * Age 18 years or older * Newly diagnosed GD * Positive TSH receptor antibodies, defined as TRAb \>1.5 IU/L * Biochemical hyperthyroidism, defined as TSH \1.5 IU/L prior to the current diagnostic episode * Inability to provide informed consent * Inability to complete the baseline assessment within the predefined study timeframe Healthy Control Group: * Age below 18 years * Known Graves' disease or previous positive TRAb measurement * Known thyroid dysfunction requiring antithyroid drug therapy or thyroid hormone replacement therapy * Inability to provide informed consent Moderate-to-Severe TED Group: * Age below 18 years * Inability to provide informed consent * Inability to complete the planned study assessment