Is sarcoidosis more common in certain areas in the united states?

Sarcoid. Some research shows that people who live rurally around farms--insecticides, chemicals etc. Have a higher incidence. There is higher incidence of caucasiian sarcoid patients having an increased susceptibility within their own family---an immune problem with increased potential to be inherited. While, although 50% of sarcoid pts. Are afro-american, hispanic --- not as commonly inc. In family.
Urban areas. Sarcoidosis is more common in urban areas compared to rural areas. It is more common in the eastern us.