Immunotherapy Utilization Among Patients With Metastatic NSCLC: Impact of Comorbidities

In patients with metastatic non-small cell lung cancer (mNSCLC), the extent to which immunotherapy utilization rate varies by comorbidities is unclear. Using the National Cancer Database from 2015 to 2016, we assessed the association between levels of comorbidity and immunotherapy utilization among mNSCLC patients. Burden of comorbidities was ascertained based on the modified Charlson-Deyo score and categorized as an ordinal variable (0, 1, and ≥2). Immunotherapy utilization was determined based on registry data. Multivariable logistic regressions were used to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) for the comorbidity score while adjusting for sociodemographic factors, histopathologic subtype, surgery, chemotherapy, radiotherapy, insurance, facility type, and other cancer history. Subgroup analyses were conducted by age and race/ethnicity. Overall, of the 89,030 patients with mNSCLC, 38.6% (N=34,382) had the comorbidity score of ≥1. Most patients were non-Hispanic white (82.3%, N=73,309) and aged 65 years and above (63.2%, N=56,300), with the mean age of 68.4 years (SD=10.6). Only 7.0% (N=6220) of patients received immunotherapy during 2015-2106. Patients with a comorbidity score of ≥2 had a significantly lower rate of immunotherapy utilization versus those without comorbidities (aOR=0.85; 95% CI, 0.78-0.93; P-trend<0.01). In subgroup analysis by age, association patterns were similar among patients younger than 65 and those aged 65-74 years. There were no significant differences in subgroup analysis by race/ethnicity, although statistical significance was only observed for white patients (comorbidity score ≥2 vs. 0: aOR=0.85; 95% CI, 0.77-0.93; P-trend<0.01). In conclusion, mNSCLC patients with a high burden of comorbidities are less likely to receive immunotherapy.