Immune-Related Adverse Events Requiring Hospitalization in Patients Receiving Immune Checkpoint Inhibitors


Key Points

  • Among immune checkpoint inhibitor–treated patients who were hospitalized, 41% were admitted for suspected immune-related adverse events and 23% for confirmed events.
  • Confirmed immune-related adverse events accounted for 5% of all oncology admissions, with 65% of these events being grade ≥ 3 adverse events. 

In a single-center analysis reported in the Journal of Oncology Practice, Balaji et al found that immune-related adverse events associated with immune checkpoint inhibitor treatment often require hospitalization and multidisciplinary management. The study involved data from patients who had received immune checkpoint inhibitors for the treatment of solid tumors and were hospitalized at an academic oncology center during a 6-month period from May to December 2017.

Hospitalization for Immune-Related Adverse Events

Among 443 patients admitted to the oncology center hospital during the 6-month period analyzed, 100 (23%) had ever received immune checkpoint inhibitors. Of these patients, 26 were receiving immune checkpoint inhibitor treatment at the time of admission and 74 had either completed or stopped treatment.

Among the 100 immune checkpoint inhibitor–treated patients, 41 (41%) were admitted for suspected immune-related adverse events and 23 (23%) for confirmed events. The median time from beginning immune checkpoint inhibitor treatment to hospitalization for an immune-related adverse event was 64 days. Confirmed immune-related adverse events accounted for 23 (5%) of all oncology admissions, with 65% of these events being grade ≥ 3 adverse events.  The most common immune-related adverse events requiring hospitalization were pneumonitis (25%) and colitis (17%).

A total of 25 patients had a known autoimmune condition prior to initiating immune checkpoint inhibitor treatment. Apart from the events recognized as immune-related, four of these patients with prior autoimmune conditions experienced a flare of their condition and two were hospitalized.

Among patients with confirmed immune-related adverse events, 91% required a subspecialist consultation, most commonly gastroenterology (22%). Improvement or resolution of immune-related adverse events occurred in 15 patients (65%) and worsening occurred in 7 (30%). These events resulted in the death of three patients (13%).

Among all immune checkpoint inhibitor–treated patients who required admission, risk of immune-related adverse event–related hospitalization was significantly greater in patients older than age 65 years (odds ratio [OR] = 5.4, 95% confidence interval [CI] =1.6–17.8) and in those who received combination immunotherapy (OR = 6.8, 95% CI = 2.0–23.2).

The investigators concluded, “A notable proportion of immune checkpoint inhibitor–treated patients are hospitalized for [immune-related adverse events], and these patients have a high demand for multidisciplinary management. Older age and combination immune checkpoint inhibitor treatment were associated with an increased risk of [immune-related adverse events]-related hospitalization. Whereas these data are from an academic center and include patients in clinical trials, with expanding use of immune checkpoint inhibitors, these data have important implications for inpatient service planning and risk stratification.”

Aanika Balaji, BS, of Johns Hopkins University, is the corresponding author for the Journal of Oncology Practice article.

Disclosure: For full disclosures of the study authors, visit

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.