Association Between Geriatric Nutritional Risk Index and Gastrointestinal Cancer Risk in Older Adults: Insights from the National Health and Nutrition Examination Survey 1999–2020

The Geriatric Nutritional Risk Index (GNRI) is a valuable tool to assess nutritional status in older adults, but its association with gastrointestinal (GI) cancer risk remains unclear. This study aimed to investigate the association between GNRI and GI cancer risk in the elderly population. Data from 18,889 participants aged 60 and older were analyzed from the National Health and Nutrition Examination Survey (NHANES) between 1999-2020. Multivariable logistic regression models were used to examine the association between GNRI and GI cancer risk, adjusting for confounding factors including age, sex, race, education, poverty-income ratio (PIR), smoking status, alcohol drinking, hypertension, and diabetes. Potential non-linear relationships were explored using generalized additive models, smooth curve fitting, and piece-wise regression analysis. A significant negative association was observed between GNRI and GI cancer risk (p = 0.005), after fully adjusting for confounders. Participants in the third quartile of GNRI had a 35% lower risk of GI cancers compared to those in the lowest quartile (p = 0.010). Piece-wise regression analysis identified a GNRI threshold of 95.25. These findings provide evidence that elevated GNRI is remarkably associated with reduced GI cancer risk among geriatric individuals.