Early death after discharge from emergency departments: analysis of national US insurance claims data

Abstract

Objective: To measure incidence of early death after discharge from emergency departments, and explore potential sources of variation in risk by measurable aspects of hospitals and patients.

Design: Retrospective cohort study.

Setting: Claims data from the US Medicare program, covering visits to an emergency department, 2007-12.

Participants: Nationally representative 20% sample of Medicare fee for service beneficiaries. As the focus was on generally healthy people living in the community, patients in nursing facilities, aged ≥90, receiving palliative or hospice care, or with a diagnosis of a life limiting illnesses, either during emergency department visits (for example, myocardial infarction) or in the year before (for example, malignancy) were excluded.

Main outcome measure: Death within seven days after discharge from the emergency department, excluding patients transferred or admitted as inpatients.

Results: Among discharged patients, 0.12% (12 375/10 093 678, in the 20% sample over 2007-12) died within seven days, or 10 093 per year nationally. Mean age at death was 69. Leading causes of death on death certificates were atherosclerotic heart disease (13.6%), myocardial infarction (10.3%), and chronic obstructive pulmonary disease (9.6%). Some 2.3% died of narcotic overdose, largely after visits for musculoskeletal problems. Hospitals in the lowest fifth of rates of inpatient admission from the emergency department had the highest rates of early death (0.27%)-3.4 times higher than hospitals in the highest fifth (0.08%)-despite the fact that hospitals with low admission rates served healthier populations, as measured by overall seven day mortality among all comers to the emergency department. Small increases in admission rate were linked to large decreases in risk. In multivariate analysis, emergency departments that saw higher volumes of patients (odds ratio 0.84, 95% confidence interval 0.81 to 0.86) and those with higher charges for visits (0.75, 0.74 to 0.77) had significantly fewer deaths. Certain diagnoses were more common among early deaths compared with other emergency department visits: altered mental status (risk ratio 4.4, 95% confidence interval 3.8 to 5.1), dyspnea (3.1, 2.9 to 3.4), and malaise/fatigue (3.0, 2.9 to 3.7).

Conclusions: Every year, a substantial number of Medicare beneficiaries die soon after discharge from emergency departments, despite no diagnosis of a life limiting illnesses recorded in their claims. Further research is needed to explore whether these deaths were preventable.

Fig 1

Cause of death and antecedent discharge diagnoses from emergency departments. Association between most common primary discharge diagnoses and most common causes of death from death certificates, for subset of deaths from 2007-08 when death certificate data were available. Thickness of line is proportional to number of beneficiaries with given discharge diagnosis who later died of given cause (see table D in appendix 1 for further details)

Fig 2

Evolution of weekly mortality risk after emergency department visits. Visit is denoted as week 0 (left). Rates calculated separately, by fifth of rate of emergency department to inpatient admission for Medicare patients, shown in columns from lowest fifth (left) to highest fifth (right). Shaded area around lines shows 95% confidence interval for mortality rates

Fig 3

Association between seven day mortality rates and rates of inpatient admission from emergency departments. Rates calculated separately by hospital admission rate. Types of hospital based on data from American Hospital Association. CAH=critical access

Fig 4

Risk ratios (and 95% confidence intervals) for early death for 20 most common diagnoses in emergency departments. Incidence of each diagnosis among all patients (admission diagnosis for admitted patients, primary discharge diagnosis for discharged patients) shown in parentheses. Risk ratios calculated as ratio of incidence of diagnosis among early deaths after discharge v frequency among all other emergency department visits (admitted and discharged). Diagnoses grouped into four categories: formal pathophysiological diagnoses of disease (such as pneumonia); syndromic diagnoses, either involving pain (such as chest pain) or not involving pain (such as dyspnea); and diagnoses related to injuries, skin conditions (such as cellulitis) or musculoskeletal pain (such as muscle sprain)