The association of macronutrient quality and its interactions with energy intake with survival among patients with ovarian cancer: results from a prospective cohort study

Background: Emerging evidence supports shifting the focus from the quantity of macronutrients to quality to obtain greater benefits for the prognosis of ovarian cancer (OC). Additionally, despite the high relevance between macronutrient quality and quantity, the interaction of these parameters on OC survival remains unknown.Objective: A multidimensional macronutrient quality index (MQI) was applied to investigate the association between overall macronutrient quality and the survival of patients with OC.Methods: A prospective cohort study was conducted with 701 females diagnosed with OC who were enrolled from 2015 to 2020. Dietary intake in-formation was obtained from a validated food frequency questionnaire. The MQI was calculated based on 3 quality indices: carbohydrate quality index (CQI), fat quality index (FQI), and protein quality index (PQI). Cox proportional hazards regression was conducted to calculate HRs and 95% CIs. Furthermore, we evaluated whether energy intake status (total energy intake and energy balance) modified the association between MQI and OC survival.Results: During a median follow-up period of 38 (interquartile: 35-40) mo, 130 deaths occurred. The prediagnosis high MQI scores were associated with substantially improved survival among females with OC (HRtertile 3 vs. tertile 1 = 0.50, 95% CI: 0.33, 0.77). For sub-indices of the MQI, higher CQI (HR = 0.60, 95% CI: 0.36, 0.99), higher FQI (HR = 0.55, 95% CI: 0.34, 0.87), and higher PQI (HR = 0.58, 95% CI: 0.35, 0.94) scores were all associated with better survival. Notably, significant interactions were observed for the MQI score with total energy intake and energy balance as well as the quantity and quality of carbohydrates on survival.Conclusions: Intake of high-quality macronutrients before diagnosis was associated with improved survival among females with OC, especially for those with energy imbalance.