Association of pre-diagnosis specific color groups of fruit and vegetable intake with ovarian cancer survival: results from the ovarian cancer follow-up study (OOPS)

Abstract

Background: The colors of fruits and vegetables (FV) reflect the presence of pigmented bioactive compounds. The evidence of pre-diagnosis specific FV color group intake contributing to ovarian cancer (OC) survival is limited and inconsistent. Methods: A prospective cohort study was conducted between 2015 and 2020 with 700 newly diagnosed OC patients. Pre-diagnosis dietary information was assessed by a validated food frequency questionnaire. We classified FV into five groups based on the color of their edible parts (e.g., green, red/purple, orange/yellow, white, and uncategorized groups). Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of specific color groups of FV before diagnosis with OC survival. Potential multiplicative and additive interactions were assessed. Results: 130 patients died during a median follow-up of 37.57 (interquartile: 24.77–50.20) months. We observed the improved survival with a higher pre-diagnosis intake of total FV (HR_{tertile 3 vs. tertile 1} = 0.63, 95%CI = 0.40–0.99), total vegetables (HR_{tertile 3 vs. tertile 1} = 0.57, 95%CI = 0.36–0.90), and red/purple FV (HR_{tertile 3 vs. tertile 1} = 0.52, 95%CI = 0.33–0.82). In addition, we observed significant dose–response relationships for per standard deviation increment between total vegetable intake (HR = 0.79, 95%CI = 0.65–0.96) and red/purple group intake (HR = 0.77, 95%CI = 0.60–0.99) before diagnosis with OC survival. Additionally, pre-diagnosis green FV intake was borderline associated with better OC survival (HR_{per standard deviation increment} = 0.83; 95%CI = 0.69–1.00). In contrast, we did not observe significant associations between pre-diagnosis intake of total fruits, orange/yellow, white, and uncategorized groups and OC survival. Conclusion: Pre-diagnosis FV intake from various color groups, especially the green and red/purple ones, may improve OC survival. Further studies are needed to validate our findings.