Minnesota-based Allina Hospitals and Clinics said it will refund at least $1.1 million to patients who were charged high interest rates on medical debt. Under terms of a settlement with Minnesota Attorney General Lori Swanson, Allina will reimburse patients who paid more than 8% annual interest on medical debt between Jan. 22, 2007, and Jan. 31, 2009. Thousands of patients might be up for reimbursement.