Changes in ambulatory utilization after switching from Medicaid fee-for-service to managed care

To observe any change in ambulatory care utilization after switching from Medicaid fee-for-service (FFS) to Medicaid managed care (MC).

We conducted a statewide longitudinal study of 21,048 adult Medicaid beneficiaries in New York State who switched from FFS to MC in 2011 or 2012, with 2 sets of controls (n = 21,048 with continuous FFS; n = 21,048 with continuous MC) who were matched on age, gender, dual-eligible status, and number of chronic conditions.

We measured ambulatory care utilization in the 12 months before and 12 months after the switch date, using regression to adjust for case mix and account for matching.

Overall, switching from Medicaid FFS to Medicaid MC was associated with greater absolute decreases over time in ambulatory visits and providers compared with controls (-1.49 visits vs continuous FFS and -1.60 visits vs continuous MC; each P <.0001; -0.10 providers vs continuous FFS and -0.12 providers vs continuous MC; each P <.0001). The subset of switchers with 5 or more chronic conditions had the greatest absolute decreases in visits (-5.88 visits vs continuous FFS and -5.98 visits vs continuous MC; each P <.0001) and providers (-1.37 providers vs continuous FFS and -1.39 providers vs continuous MC; each P <.0001). Significant decreases in visits and providers were also observed for switchers with 3 to 4 chronic conditions but not for those with 0 to 2 chronic conditions.

Switching from Medicaid FFS to Medicaid MC was associated with a decrease in ambulatory utilization, especially for the sickest patients.