Patient-Reported Outcome Measures After Out-of-Hospital Cardiac Arrest: A Prospective Methodological Analysis of Retention and Follow-Up Completeness Within the REVIVE Pathway

Abstract

Introduction

Cardiac arrest is the loss of mechanical cardiac function and the absence of systemic circulation. When it occurs out-of-hospital it is defined out-of-hospital cardiac arrest (OHCA). Survival after OHCA does not fully capture recovery, as survivors often experience persistent cognitive, psychological, and functional consequences. Patient-reported outcome measures (PROMs) are essential to assess these domains, but their longitudinal collection in routine survivorship care depends on patient engagement and retention over time. REVIVE is a regional hub-and-spoke survivorship pathway implemented within the Cardiac Arrest Registry of the Lombardy Region (LombardiaCARe) network to coordinate post-discharge follow-up after OHCA and standardize the assessment of patient-reported outcomes.

Objectives

To describe the structure of PROM collection within REVIVE and to evaluate patient retention, evaluability, and follow-up completeness over the 2025 calendar year.

Methods

We conducted a descriptive analysis of the REVIVE study between January and December 2025. During this period, 1,663 OHCA events were admitted to participating hospitals, 127 patients were eligible for the REVIVE pathway, 99 were contacted by the hub psychologist after signing informed consent, and 67 completed at least one assessment. REVIVE is structured as a hub-and-spoke pathway, with a specialist hub coordinating post-discharge follow-up and outcome assessment across participating hospitals. PROMs and related outcomes were collected at predefined timepoints and included discharge, 1 month, 3 months, and 6 months after the OHCA event. The PROMs assessed were anxiety and depression (HADS), post-traumatic stress symptoms (IES-R), cognitive performance (MoCA), and health-related quality of life (EQ-5D-5L), together with a clinical semi-structured interview. The analysis focused on the number of patients contributing at each timepoint and on the availability of at least one evaluable PROM per patient.

Results

Among the 99 consenting patients, 67 (67.7%) were evaluable and formed the analytic denominator. At the visit level, 46 patients had at least one PROM recorded at discharge, 49 at 1 month, 52 at 3 months, and 49 at 6 months. Domain-level completeness was high: HADS was available in 66 of 67 evaluable patients (98.5%), while MoCA and EQ-5D VAS were available in all evaluable patients (67/67, 100%). These results suggest that the main methodological challenge was not baseline collection, but maintaining patient engagement across repeated assessments, which in PROM-based survivorship care is inherently patient-driven rather than passive.

Conclusions

PROMs add value beyond survival by capturing outcomes that matter to OHCA survivors, but their validity depends on sustained patient engagement throughout follow-up. In REVIVE, the main challenge was not baseline collection, but maintaining retention in a patient-driven and psychologically sensitive assessment process, where readiness to participate may vary over time. These findings support clear definition of the evaluable cohort, transparent reporting of timepoint-specific completeness, and retention-oriented strategies to improve the quality and interpretability of longitudinal PROM data.