The strong uptick in Medicare services being performed in ambulatory surgery centers over the past several years is largely due to the migration of services — particularly ophthalmology and gastrointestinal— from hospital-based settings to freestanding ASCs, according to a new, independent study of ASC growth from 2001 to 2007.
Medicare spending on ASC services grew annually by an average rate of 9.7% between 2000 and 2007, according to the report issued by KNG Health Consulting. Researchers determined that 70% of the growth in Medicare services provided by ASCs was attributable to procedures moving from the hospital setting to ASCs. For example, the ASC market share of GI services grew from 17.3% to 36.6% between 2000 and 2007, while the HOPD market share of those procedures fell from 75% to less than 60%, and the market share for physicians’ offices remained roughly the same at 5%.
What the study did not find was any merit to the charge lodged by ASC critics that physician-ownership of surgery centers leads to overutilization of services. "We find little evidence that induced demand is a driver of ASC service volume," the authors write. "We found that most of the growth in Medicare services since 2000 resulted from a movement of services from the HOPD to the ASC."
For the 2 highest volume ambulatory services provided by ASCs — GI and ophthalmology — 75% and 94% of the growth in ASC market share, respectively, was due to those services migrating from hospitals to ASCs, according to the study, which was commissioned by the ASC Coalition.
The authors attributed the remaining 30% of overall ASC growth to a general expansion of ambulatory services in all settings due to population changes, new technologies, expanded insurance coverage and other trends, such as changes in cancer screening guidelines.
"This is the first study of its kind that has tried to explain why the industry has grown so much and where that growth is coming from," says Marian Lowe, senior vice president of federal health policy for Strategic Health Care in Washington, D.C. The "paucity of data" about ASC growth has left the industry "exposed to criticism," says Ms. Lowe, who will be speaking about industry trends at OSM’s OR Excellence conference in San Francisco this fall. "Unlike what some of our critics have suggested, ASCs are not inducing demand."
—Irene Tsikitas
