EPIDEMIOLOGIC studies on modifiable factors after a prostate cancer (PCa) diagnosis remain inconclusive. Postdiagnosis smoking and high-fat dairy intake increase all-cause and PCa-specific mortality risks, whereas physical activity improves physical functioning and reduces PCa-specific mortality. Obesity is linked to poorer prognosis, though this weakens when accounting for pathology. Certain dietary components, such as tomatoes and cruciferous vegetables, show promise in improving PCa survival, but findings lack replication. Behavioural scores combining multiple risk factors suggest that nonsmoking, a healthy BMI, vigorous physical activity, and a healthy diet may improve PCa progression and survival.
Dietary indices have been developed to assess specific dietary patterns’ effects on health. Inflammatory and insulinemic dietary scores, based on blood biomarkers, are associated with advanced PCa and disease progression. Diet classification systems like the Healthy Eating Index (HEI) and plant-based diet indices (PDIs) are linked to lower risks of total and lethal PCa, as well as disease progression. However, postdiagnostic evidence is limited across diverse populations.
This study examined whether lifestyle scores from White populations apply to others by evaluating associations between lifestyle and dietary scores and risks of PCa, cardiovascular disease (CVD), and overall mortality in a multiethnic cohort of men with nonmetastatic PCa. Healthier postdiagnostic lifestyle habits were associated with lower overall mortality, mainly due to reduced CVD-related deaths rather than PCa-specific mortality. Proinsulinemic and proinflammatory diets were linked to increased CVD-related mortality in PCa patients.
Three lifestyle scores – ‘2015 Score’, ‘2021 Score’, and ‘2021 Score + Diet’ – showed inverse trends for PCa mortality risk. The 2015 Score was associated with a 68% lower risk of lethal PCa and a 32% reduction in PCa mortality for men scoring 5–6 points pre- and postdiagnosis compared to those scoring 0–1. The 2021 Score showed mixed associations across different cohorts, likely due to variations in timing and racial composition. However, all lifestyle scores consistently correlated with lower all-cause mortality, supporting their role in improving survival, particularly by reducing CVD mortality risk.
Index-based dietary patterns were not linked to PCa-specific mortality, though associations varied by race and ethnicity. Inflammatory and insulinemic dietary indices significantly correlated with PCa-specific mortality in Japanese American and Latino men but not in other populations. Differences may stem from dietary habits and assessment methods. Nonetheless, postdiagnostic healthy diets were associated with lower all-cause and CVD-related mortality, underscoring the benefits of general dietary recommendations for men with nonmetastatic PCa.
Katie Wright, EMJ
Reference
Wang A et al. Race and ethnicity, lifestyle, diet, and survival in patients with prostate cancer. JAMA Netw Open. 2025;8(2):e2460785.
