Retrospective analysis on association of body mass index and immune checkpoint inhibitor response.

person Akshee Batra University of Vermont, Burlington, VT info_outline Akshee Batra, Abhinav Vyas, Atulya Aman Khosla, Akshit Chitkara, David Alejos, Xiaocao Xu, Karan Jatwani, Hibba tul Rehman, Shahid Sattar Ahmed, Rohit Singh

Authors person Akshee Batra University of Vermont, Burlington, VT info_outline Akshee Batra, Abhinav Vyas, Atulya Aman Khosla, Akshit Chitkara, David Alejos, Xiaocao Xu, Karan Jatwani, Hibba tul Rehman, Shahid Sattar Ahmed, Rohit Singh Organizations University of Vermont, Burlington, VT, North Alabama Medical Center, Florence, AL, Department of Internal Medicine, William Beaumont University Hospital, Royal Oak, MI, University of California, Riverside, Riverside, CA, University of Vermont Medical Center, Burlington, VT, Department of Hematology and Oncology, University of Vermont Medical Center, Burlington, VT, Roswell Park Comprehensive Cancer Center, Buffalo, NY, University of Vermont College of Medicine, Burlington, VT, Division of Hematology Oncology, University of Vermont Larner College of Medicine, Burlington, VT Abstract Disclosures Research Funding No funding sources reported Background: The relationship between Body Mass Index (BMI) and cancer is a complex. We aim to study the impact of BMI on the response to immunotherapy in cancer patients. Methods: We did a retrospective observational study to investigate the influence of different BMI groups on patients receiving Immune Checkpoint Inhibitors (ICIs) at the University of Vermont Cancer Centre. We examined the medical records of people who received ICIs between January 2017 and June 2022 and collected demographic data, including age, sex, ethnicity, cancer stage, BMI, type and metastasis. We looked at Hazard Ratio (HR) in BMI subcategories compared to normal. The occurrence of immune-related adverse events (irAEs), metastasis and receipt of chemotherapy in different BMI subgroups was evaluated with relative risks (RRs). Results: A total of 288 cases were identified, out of which 269 had documented BMI, including 58% males, 94.8% whites with 64.17 years mean age. Lung cancer was most common at 41.3%, 46.5% were and 63.2% were stage 4. Total 71.4% of people received Pembrolizumab and 42.8% had concomitant chemotherapy. The median ECOG was 1 and the Charlson comorbidity index was 6. irAEs observed in 33% of cases, whereas mortality in 36%. The BMI distribution had 36.1% normal, 27.1% overweight, 16.5% obese, 14.5% extremely obese and 5.6% underweight. The HR in underweight subgroup was significant at 5.223 (p <0.001; 95CI: 2.2 to 12.4) compared to normal. The HR of overweight, obese and extremely obese decreased with HR of 1.15, 0.77 and 0.18 respectively but wasn’t significant as seen in Table 1. Table also shows that relative risk of irAEs, cancer stage, metastasis and concomitant chemotherapy were not significant. Conclusions: Clinically significant association was found between being underweight and mortality in cancer patients receiving immunotherapy. BMI Categories Survival Adverse Reaction Chemotherapy Metastasis Brain Metastasis HR p value RR p value RR p value RR p value RR p value Underweight 5.22 <.001 0.81 1.16 0.42 1.60 0.27 0.50 0.25 2.27 Overweight 1.15 0.67 0.19 1.55 0.37 1.34 0.80 1.09 0.65 0.81 Obese 0.77 0.51 0.99 1.01 0.90 1.05 0.34 0.69 0.39 0.59 Extremely obese 0.18 0.09 0.55 1.28 0.27 0.62 0.43 1.38 0.15 0.32