During the first year of hemodialysis (HD), patients readmitted to a hospital are at higher risk of poor outcomes the following year than patients with no hospital admissions, a new study found.
Laura C. Plantinga, PhD, and colleagues at Emory University in Atlanta used the US Renal Data System (USRDS) database to identify 128,593 incident HD patients with Medicare coverage. During the first year of HD, 51% had no hospital admissions, 18.5% had a hospital admission and were readmitted within 30 days of discharge, and 30.5% had a hospital admission but were not readmitted.
Patients who were readmitted had a significant 3.3-fold increased risk of death and 4.5-fold increased risk of hospitalization, respectively, in the second year on dialysis compared with patients with no hospital admissions. The readmitted patients also had a significant 48% decreased likelihood of kidney transplantation. Patients who were admitted to a hospital but not readmitted had a significant 1.8-fold and 2.2-fold increased risk of death and hospitalization, respectively, and 15% decreased likelihood of kidney transplantation in the second year on dialysis.
“Our findings imply that the detrimental effects of readmission are long-lasting and affect a large proportion of incident dialysis patients,” the authors wrote in BMC Nephrology. “To our knowledge, this is the first study to identify patients with hospital readmissions in their first year of dialysis as a group at high risk for poor long-term outcomes.”
In a discussion of possible explanations for their findings, Dr Plantinga and her collaborators noted that hospital readmission could be a marker for patients with a poor long-term prognosis. “We found patients with readmissions in the first year of dialysis had higher rates of comorbidities than patients who were either not admitted or admitted but not readmitted.”
Another possibility is that that physiologic changes in patients with end-stage renal diseases during hospitalization contribute to poor long-term outcomes, the investigators stated.
Noting that the readmission rate in their study (18.5%) is lower than the USRDS estimated of 35% among prevalent dialysis patients, the authors explained that their analysis was at the patient level as opposed to the admissions level and focused only on incident HD patients who survived at least 1 year.
In a discussion of study limitations, the investigators acknowledged the potential for misclassification of variables in administrative databases such as the USRDS database and noted that they did not have access to laboratory data during follow-up, which may have provided insight into preliminary markers of poor outcomes.
Ross KH, Jarr BG, Lea JP, et al. Long-term outcomes among Medicare patients readmitted in the first year of hemodialysis: a retrospective cohort study. BMC Nephrol. 2019;20:285. doi.org/10.1186/s12882-019-1473-0