The Affordable Care Act (ACA) prohibits turning people down for health insurance on the basis of preexisting conditions.  Insurers found a loophole by grouping all drugs (including generics) for one condition together in the highest cost-sharing tier. The ensuing high costs discourage enrollment in such plans. Researchers examined HIV drugs in plans of 12 states, including a mixture of expanded and not-expanded Medicaid states. A similar pattern was found in other studies that examined drugs used for other chronic conditions. Kelli Kennedy reported on the study in her piece "Study: Insurers may be using drug costs to discriminate" for The Associated Press that was published carried by KRQE NEWS 13 on 1-28-15. The study itself by DB Jacobs and BD Sommers "Using Drugs to Discriminate--Adverse Selection in the Insurance Marketplace" was published by The New England Journal of Medicine Vol. 372:5 on 1-29-15.