[..] In one study of a large Accountable Care Organization, PCP relocation, retirement, or death was the dominant factor associated with the reassignment of approximately one-third of Medicare beneficiaries to a new Accountable Care Organization every year.
This cohort study used Medicare administrative claims data for a 20% random sample of continuously enrolled, fee-for-service beneficiaries. For the main study sample as well as subgroup analyses, we included beneficiaries visiting a PCP for at least 1 evaluation and management visit from January 1, 2008, to December 31, 2017. We then limited the study sample to PCPs who treated 30 or more Medicare beneficiaries during a 1-year period and their patients.
[..] We defined the date of exit as the last month a PCP billed Medicare for office-based services with no subsequent Medicare services recorded. To ensure that we could observe a sufficient preperiod, PCPs who practiced at the same practice for less than 2 years before exiting were excluded from the study sample. The study sample also excluded beneficiaries who lost a PCP from 2016 to 2017 because the sample period restricted our ability to follow up with beneficiaries 2 years after PCP exit.
Overall, 90,953 PCPs billed services for 30 or more Medicare beneficiaries from 2008 to 2017, of whom 9491 (10.4%) exited Medicare from 2010 to 2015.
[..] In the first year after a PCP’s exit, annual primary care visits decreased 18.4% (95% CI, −19.8% to −16.9%), or −0.97 visits, from a baseline mean of 5.3 visits annually. During the same period, specialist visits increased 6.2% (95% CI, 5.4%-7.0%), or 0.6 visits, from a baseline mean of 9.5 visits annually among exposed beneficiaries compared with unexposed beneficiaries. The observed changes in the rates of PCP and specialist visits persisted for 2 years after PCP exit.
[..] In the first year after a PCP’s exit, urgent care visits increased 17.8% (95% CI, 6.0%-29.7%), or 1.7 visits, from a baseline mean of 9.6 visits per 1000 patients annually among exposed beneficiaries compared with unexposed beneficiaries. During the same period, emergency department visits increased 3.1% (95% CI, 1.6%-4.6%), or 2.3 visits, from a baseline average of 74.1 visits annually per 100 patients.
Changes in health care use corresponded to an increase in total Medicare spending of $189 (95% CI, $30-$347) per patient the first year after a PCP’s exit. An increase in spending of $189 per beneficiary translates to $46,350 of additional Medicare spending attributable to each exiting PCP annually (based on a mean caseload of 49 Medicare fee-for-service beneficiaries per year in the 20% sample, multiplied by 5 to approximate a 100% sample). Inpatient visits and the probability of death did not significantly change between exposed and unexposed beneficiaries.”
Full article, Sabety AH, Jena AB and Barnett ML. JAMA Internal Medicine 2020.11.16