Thirty-Day Hospital Readmissions in Adults: Associated Factors, Potential Avoidability and Prevention Strategies—A Targeted Scoping Review

Thirty-day hospital readmissions are widely used to assess outcomes following hospital discharge and may reflect clinical vulnerability, continuity of care, and healthcare organization. However, not all readmissions are potentially avoidable, and readmission rates alone do not directly measure the quality of hospital care. This targeted scoping review aimed to describe and organize the evidence identified on 30-day hospital readmissions in adults, focusing on associated factors, potential avoidability, and prevention strategies. The review was conducted according to the JBI methodology and reported in accordance with PRISMA-ScR. PubMed, Embase, and Cairn were searched for studies published between 2015 and 2025 using a targeted, condition-informed search strategy. Study selection and data charting were performed by a single reviewer. Additional literature and French institutional data were analyzed separately from the primary corpus. The protocol was registered on the Open Science Framework. Twenty-three studies were included in the primary corpus, complemented by six additional sources. Readmissions were associated with clinical and disease-related factors, frailty and functional dependence, medication-related factors, and social, territorial, and organizational conditions. Only two studies directly assessed potential avoidability using an explicit classification or assessment method. Prevention strategies were predominantly multimodal and included discharge planning, medication management, transitional care, post-discharge follow-up, coordination with primary care, home-based services, and risk stratification. Their reported effects on 30-day readmissions were heterogeneous, and only one randomized controlled trial was identified, with no statistically significant overall reduction in readmissions. These findings highlight the multifactorial nature of 30-day readmissions and the importance of distinguishing associated factors, potentially modifiable care processes, intervention effects, and potential avoidability. Further research should use more homogeneous definitions of potential avoidability and rigorously evaluate transitional and organizational interventions across diverse healthcare settings.