Abstract
Although indications for immune checkpoint inhibitors (ICIs) have dramatically increased in the past decade, ICIs have been associated with autoinflammatory immune-related adverse events, which can resemble autoimmune diseases (ADs). Little is known about the impact of baseline AD on mortality in cancer patients treated with ICIs. Here, we identified 17 497 patients with preexisting autoimmune diagnoses prior to treatment with antiprogrammed cell death receptor-1 or antiprogrammed cell death ligand-1 therapy and 17 497 matched controls through the TriNetX Diamond network of more than 200 million patients across the United States and Europe. Using a Cox proportional hazards model, we found that patients with history of AD were not at higher risk of mortality than non-AD patients (hazard ratio [HR] = 1.03, 95% confidence interval [CI] = 1 to 1.07; P = .05). Additionally, history of Hashimoto disease (HR = 0.75, 95% CI = 0.62 to 0.90; P = .002) and vitiligo (HR = 0.52, 95% CI = 0.34 to 0.81; P = .003) were statistically significantly associated with decreased mortality. This suggests that underlying AD need not be a contraindication to inclusion in clinical trials and administration of ICI for treatment of cancer.