As consumer directed health plans have grown, research continues into who goes into one and what their cost and health outcomes are. The Government Accounting Office looked at the experience of two large employers and surveyed the literature. (GAO Study) GAO examined a large private and a large public employer who added a CDHP option. It compared the health costs of the group which went into the CDHP with those of the employees who didn’t, over the two years before the CDHP was offered, and for several years after the plan option became available.
GAO found that the persons who enrolled in the CDHP had both lower average annual spending and lower utilization rates of services in the time period before CDHP enrollment; $1505 less in the public employer and $566 less in the private firm. Some of this may be explained by the CDHP enrollees being about three years younger and slightly more likely to be male and to elect single coverage. In the time period after enrollment, the CDHP members continued to have lower costs; on average $478 versus $879 annual increase at the public employer and $152 versus $206 at the private one. Interestingly, at the public employer the average rate of increase was actually higher for the CDHP group, which may reflect regression to the mean. Utilization rates were generally lower as well, although preventive services increased for the CDHP group versus the non-CDHP one. GAO did not attempt to assess changes in health status or outcomes.
Much is often made of the fact that CDHP enrollees appear to be healthier and to spend less on health care than persons in other plans. Without an exhaustive evaluation of the actual health status of CDHP enrollees, it is easy to conflate spending less with better health status. It may be that people inclined to sign up for CDHP plans are already cost-conscious and careful consumers, which is what we are supposedly aiming for in the system overall. Even relatively high-cost patients seem to spend less in a CDHP and it is not clear that their outcomes are worse. Continuing research will help monitor these issues.