Lin KK, Lee JS, Hou CH, et al. - Researchers conducted this population-based matched case-control study to determine the sociodemographic and risk factors for keratoconus (KC) patients with a nationwide Asian data base. They carried out secondary data analysis on the Taiwan National Health Insurance Research Database. In total, 5,055 patients with KC were matched with 20,220 controls. Individuals living in suburban and rural areas, as compared with those living in urban areas, had a lower KC odds ratio. The authors discovered that patients with hyperlipidemia, depression or DM were less likely to have KC, and higher KC odds ratios were showed in patients with asthma, allergic rhinitis, astigmatism, myopia or Down syndrome.