Associations of the Geriatric Nutritional Risk Index with high risk for prostate cancer: A cross-sectional study.

Objectives: The geriatric Nutritional Risk Index (GNRI) is an effective tool to assess the nutritional status of the elderly. However, the relationship between the GNRI and the risk for prostate cancer (PCa) remains uncertain in middle-aged and older men. The aim of this study was to investigate the association between the GNRI and the risk for PCa by analyzing the serum total (tPSA) and free prostate-specific antigen (fPSA) levels (including percent fPSA [%fPSA]).

Methods: Data for this study were obtained from 7396 men ≥40 y of age from the 2001-2010 National Health and Nutrition Survey (NHANES). We obtained the tPSA and fPSA and calculated the %fPSA and the GNRI. Participants with %fPSA >25% and tPSA <4 ng/mL were defined as high PCa risk. The relationship between the GNRI and serum PSA levels was investigated using a linear regression model. The odds ratios (ORs) and 95% confidence intervals (CIs) for the association between the GNRI and PCa risk were estimated by a logistic regression model. The non-linear relationship was also characterized by a restricted cubic spline regression model.

Results: The median of tPSA, fPSA, and %fPSA was 0.90, 0.26, and 29%, respectively. The mean of the GNRI was 29. The proportion of participants in the low PCa- and high PCa-risk groups was 93% and 7%, respectively. There was a negative and linear correlation between the GNRI and serum tPSA and fPSA levels in all models. However, no association between the GNRI and the %fPSA was observed. In the adjusted model, lower GNRI was associated with higher PCa risk (OR, 0.570; 95% CI, 0.415-0.784; P = 0.001). The restricted cubic spline regression model showed a non-linear and negative association between the GNRI and PCa risk (P = 0.020), with inflection points of 109.148.

Conclusion: The results of this study suggest that nutritional status, as represented by the GNRI, is associated with the risk for PCa.