Characteristics and predictors of mortality among frequent users of an Emergency Department in Switzerland.

OBJECTIVES: Frequent Emergency Department (ED) users have an elevated mortality, yet little is known about risk factors. Our aim was to characterize deceased frequent ED users and determine predictors of mortality. METHODS: This is a post-hoc analysis of all-cause mortality among frequent ED users participating in a randomized clinical trial on case management at the Lausanne University Hospital (Switzerland). We enrolled 250 frequent ED users (5+ visits/past year) in a 12-month randomized clinical trial; those with an estimated survival of fewer than 18 months were excluded. The primary outcome was 12-month all-cause mortality. We performed descriptive statistics to compare the baseline characteristics of living and deceased participants, and examined predictors of all-cause mortality using logistic regressions, including age adjustment. RESULTS: Twenty of the 250 (8%) frequent users died during the 12-month follow-up. Seven (35%) deaths were because of cardiac causes and six (30%) were because of cancer. The median age at death was 71 years. Deceased participants were older and more likely to report any somatic determinant, chronic illness, and medical comorbidity. Age (odds ratio 1.07, 95% confidence interval 1.04-1.11) and medical comorbidity (odds ratio 4.76, 95% confidence interval 1.86-12.15) were statistically significant predictors of mortality. CONCLUSION: Despite excluding those with an estimated survival of fewer than 18 months, 8% of frequent ED users died during the study. Age and medical comorbidity were significant predictors of mortality. Interventions, such as case management, should target older frequent ED users and those with multiple medical conditions, and future research should explore their potential impact on mortality.

Characterizing the vulnerability of frequent emergency department users by applying a conceptual framework: a controlled, cross-sectional study.

BACKGROUND: Frequent emergency department (ED) users meet several of the criteria of vulnerability, but this needs to be further examined taking into consideration all vulnerability's different dimensions. This study aimed to characterize frequent ED users and to define risk factors of frequent ED use within a universal health care coverage system, applying a conceptual framework of vulnerability. METHODS: A controlled, cross-sectional study comparing frequent ED users to a control group of non-frequent users was conducted at the Lausanne University Hospital, Switzerland. Frequent users were defined as patients with five or more visits to the ED in the previous 12 months. The two groups were compared using validated scales for each one of the five dimensions of an innovative conceptual framework: socio-demographic characteristics; somatic, mental, and risk-behavior indicators; and use of health care services. Independent t-tests, Wilcoxon rank-sum tests, Pearson's Chi-squared test and Fisher's exact test were used for the comparison. To examine the -related to vulnerability- risk factors for being a frequent ED user, univariate and multivariate logistic regression models were used. RESULTS: We compared 226 frequent users and 173 controls. Frequent users had more vulnerabilities in all five dimensions of the conceptual framework. They were younger, and more often immigrants from low/middle-income countries or unemployed, had more somatic and psychiatric comorbidities, were more often tobacco users, and had more primary care physician (PCP) visits. The most significant frequent ED use risk factors were a history of more than three hospital admissions in the previous 12 months (adj OR:23.2, 95%CI = 9.1-59.2), the absence of a PCP (adj OR:8.4, 95%CI = 2.1-32.7), living less than 5 km from an ED (adj OR:4.4, 95%CI = 2.1-9.0), and household income lower than USD 2,800/month (adj OR:4.3, 95%CI = 2.0-9.2). CONCLUSIONS: Frequent ED users within a universal health coverage system form a highly vulnerable population, when taking into account all five dimensions of a conceptual framework of vulnerability. The predictive factors identified could be useful in the early detection of future frequent users, in order to address their specific needs and decrease vulnerability, a key priority for health care policy makers. Application of the conceptual framework in future research is warranted.