Impact of Falls Within 3 Months on the Short-Term Prognoses of Elderly Patients in Intensive Care Units: A Retrospective Cohort Study Using Stabilized Inverse Probability Treatment Weighting

Abstract

Background: Falls are a major public health problem in the older adults that can lead to poor clinical outcomes. There have been few reports on the short-term prognoses of older critically ill patients, and so we sought to determine the impact of falls on elderly patients in intensive care units (ICUs). Patients and Methods: This retrospective study of 4503 patients (aged 65 years or older) analyzed data in the Medical Information Mart for Intensive Care-III critical care database. Of those, 2459 (54.6%) older adults are males, and 2044 (45.4%) older adults are females. Based on information from the medical care record assessment forms, patients were classified into the following two groups based on whether they had a fall within the previous 3 months: falls (n=1142) and nonfalls (n=3361). The primary outcomes of this study were 30-and 90-day mortality. Associations between the results of the Kaplan-Meier (KM) survival analysis, Cox proportional-hazards regression models, and subgroup analysis and its outcomes were analyzed using stabilized inverse probability treatment weighting (IPTW). Results: KM survival curves with stabilized IPTW indicated that 30-and 90-day survival rates were significantly lower in elderly critically ill patients with a history of falls within the previous 3 months than in those patients without a history of falls (all p<0.001). Multivariate Cox proportional-hazards regression analysis indicated that 30-and 90-day mortality rates were 1.35 times higher (95% confidence interval [CI]=1.16–1.57, p<0.001) and 1.36 times higher (95% CI=1.19–1.55, p<0.001), respectively, in elderly critically ill patients with a history of falls within the previous 3 months than in those patients without a history of falls. Conclusion: Experience of falls within the previous 3 months prior to ICU admission increased the risk of short-term mortality and affected the prognoses of elderly patients. Falls should therefore receive adequate attention from clinical healthcare providers and management decision-makers.