Effectiveness and Adherence of Nutritional Management via Electronic Patient-Reported Outcomes Platform in Patients With Cancer: Multicenter Prospective Longitudinal Cohort Study.

Background: Personalized nutritional management during cancer remains challenging in clinical practice. The development of an electronic patient-reported outcome platform (ePROM) provides novel opportunities. Objective: This study aimed to evaluate the effectiveness and adherence of nutritional management using ePROM in patients with cancer. Methods: This multicenter prospective longitudinal cohort study included 6124 patients diagnosed with cancer. Exposure was defined as adherence to the ePROM journal, measured by the longest consecutive month of weekly entries. Dietary intake was reported via food selection, voice input, or meal photos. The primary outcomes were adequate energy intake (EI, ≥25 kcal/kg/day) and protein intake (PI, ≥1 g/kg/day), defined according to European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines. Logistic regression analysis was conducted to identify the factors associated with EI and PI, reporting odds ratios (ORs) and 95% CIs. A restricted cubic spline plot was used to illustrate the association between the adjusted ORs and adherence duration. The semMediation approach was applied to assess the impact of multiple mediators on the outcomes. Results: The study cohort comprised 3741/6124 (61.1%) men and 2383 (38.9%) women, with a median age of 60.85 (IQR 53.3-68.3) years. Overall, 1024/6124 (16.7%) and 2591/6124 (42.3%) patients achieved adequate EI and PI scores, respectively. At one month, 499/1024 patients (48.7%) in the adequate EI group and 1287/2591 (49.7%) in the adequate PI group continued journaling, compared with 1879/5100 (36.8%) and 1091/3533 (30.9%) in the corresponding inadequate groups (P<.001). This trend remained significant in the second, third, and sixth months. Logistic regression analysis demonstrated that longer adherence to ePROM journaling was independently associated with adequate EI (OR 1.05, 95% CI 1.01-1.08; P=.01) and PI (OR 1.22, 95% CI 1.16-1.28; P<.001) after adjusting for confounders. Mediation analysis revealed that most symptoms did not significantly mediate these effects, except for constipation, reflux, and delirium, which showed statistical significance but minimal indirect effects. Conclusions: Nutritional management via ePROM is a feasible approach, with improved effectiveness as adherence duration increases. The observed benefits resulted primarily from direct effects rather than from symptom improvement.