The Shizuoka Study of a Population-Based Retrospective Cohort for the Evaluation of Risk of Pressure Injury in the Elderly

<b>Objective:</b> The risk of pressure injuries (PIs) is increasing in Japan, where an aging population imposes substantial health care burdens. <b>Approach:</b> This retrospective cohort study utilizing the Shizuoka Kokuho Database evaluated factors associated with PI development in hospitalized patients. <b>Results:</b> An analysis of over 546,000 patients aged ≥65 years from 2012 to 2022 identified 6,372 PI cases. Cox regression analyses revealed that male sex (hazard ratio [HR] 1.32, 95% confidence interval [CI]: 1.25-1.39), advanced age (HR 8.54, 95% CI: 7.40-9.87 for ≥95 years vs. 65-69 years) and comorbidities such as neurological disorders (HR 1.87, 95% CI: 1.72-2.04), dementia (HR 1.69, 95% CI: 1.59-1.80), and congestive heart failure (HR 1.19, 95% CI: 1.12-1.27) were associated with increased PI risks. Conversely, antihyperlipidemic drugs may be associated with a lower PI risk (HR 0.69, 95% CI: 0.65-0.74). Due to data limitations, factors such as nutritional status, mobility, and caregiver support could not be evaluated. <b>Innovation:</b> This study is the first in Japan to leverage big data to identify high-risk groups for PIs, particularly among elderly individuals with specific comorbidities. This approach offers actionable insights into PI management, potentially enhancing care strategies and preventive guidelines. <b>Conclusion:</b> Male sex, advanced age, and comorbidities, including neurological disorders, dementia, psychosis, and congestive heart failure, were identified as primary PI risk factors. Conversely, antihyperlipidemic drug use may be associated with a lower PI risk. These findings highlight the need for comprehensive, targeted prevention strategies to reduce the risk of PI in elderly hospitalized patients.