These plans operate at scale. They choose carriers, set benefits and contract with vendors. In many states, they are among the largest purchasers of commercial health care, so cost growth compounds quickly. That purchasing power can also be used to push for better results and more predictable spending.
Costs are rising for a few clear reasons: wide variation in provider prices and performance as well as increasing unit costs, pharmacy trend driven by the rapid growth in GLP 1 and specialty drug use, and high spending among a small number of members with complex needs. In these areas, poor coordination and lack of vendor accountability can drive costly utilization (ER visits, hospital stays) and fragmentation.