Impact of Radiation Therapy on Inpatient Outcomes Among Patients With Lung Cancer

Purpose/Objective(s) Hospitalizations during cancer treatment not only disrupt treatment but are also associated with increased healthcare resource utilization and negatively impact patient quality of life. While the impact of chemotherapy on hospitalizations among patients with lung cancer has been well-studied, the effect of radiation therapy in hospitalized patients with lung cancer is poorly studied. Materials/Methods We interrogated the nationwide inpatient sample from 2015-2017 for admissions in patients with lung cancer with and without a history of radiation therapy using appropriate ICD-10 diagnosis codes. Data related to baseline characteristics and inpatient outcomes were collected and analyzed using data management and decision management software. Results A total of 896,245 hospitalizations among patients with lung cancer were identified, out of which, 10.97% (96,775) had undergone radiation therapy. The mean age for hospitalizations in the radiation therapy group was 74.97±10.71 years and 50.95% were males. Majority of the patients in the radiation group were Caucasians (77.56%) and 87.67% of the hospitalizations were unplanned. Medicare (63.70%) and private insurance (21.91%) were identified as the primary payers in majority of these admissions. Admissions in the radiation group were noted to have a higher incidence of hypothyroidism (10.64% vs 9.96%, p<0.0001), electrolyte imbalance (32.05% vs 31.84%, p<0.0001) and coagulopathy 8.18% vs 7.26%, p<0.0001). The radiation group also did not demonstrate an increased incidence of atrial fibrillation (15.28% vs 15.93%, p=0.20) and stroke (2.98% vs 3.44%, p=0.06). Admissions in the radiation group were found to have a decreased all-cause inpatient mortality (6.03% vs 8.25%, p<0.0001) and median total hospital charges ($9,240 vs $10,324, p=0.009) when compared to the group that did not receive radiation. However, no difference between the median length of stay was noted [4(2,7) vs 4(2,7)]. Conclusion Unplanned admissions are common among patients with lung cancer after radiation therapy. Radiation therapy was found to be associated with hypothyroidism, electrolyte imbalance and coagulopathy. In line with recent evidence, thoracic radiation did not appear to increase the risk of atrial fibrillation and stroke in our analysis. Further prospective research studies are needed to find ways to reduce non-elective admissions in cancer patients who have received radiation therapy. Perhaps prompt recognition and intervention of hypothyroidism, electrolyte imbalances, and coagulopathies may help improve overall inpatient outcomes in these patients.