The effect of providing Medicare Advantage enrollees diagnosed with cancer additional time to reassess enrollment.

Introduction: Beneficiaries enrolled in Medicare Advantage (MA) and newly diagnosed with cancer may be incentivized to switch coverage, particularly if their MA plan restricts their access to cancer care. Beginning January 2019, the deadline to disenroll from an MA plan changed from February 14 to March 31 and, for the first time, beneficiaries could switch to a different MA plan as opposed to having to enter traditional Medicare. Methods: We used 2016-2019 Surveillance, Epidemiology, and End Results (SEER) Medicare data to conduct a difference-in-differences analysis, estimating the effect of this new policy on rates of MA plan switching 1 month and 2 months after diagnosis. Results: For beneficiaries diagnosed with cancer in March, the policy was associated with a modest increase in both overall rates of switching and in switching to a new MA plan 1 month after diagnosis. Results indicated that the policy had a modest positive effect on changes in Medicare coverage for enrollees diagnosed in January when outcomes were measured 2 months after diagnosis. Conclusion: Relaxing enrollment rules for MA enrollees may not exacerbate adverse selection into traditional Medicare, given this evidence that beneficiaries with high-cost new diagnoses rarely exercised the option to change their MA plan.