Potentially Preventable Intensive Care Unit Admissions in the United States, 2006-2015

Abstract

Rationale: Increasing intensive care unit (ICU) beds and the critical care workforce are often advocated to address an aging and increasingly medically complex population. However, reducing potentially preventable ICU stays may be an alternative to ensure adequate capacity.Objectives: To determine the proportions of ICU admissions meeting two definitions of being potentially preventable using nationally representative U.S. claims databases.Methods: We analyzed claims from 2006 to 2015 from all Medicare Fee-for-Service (FFS) beneficiaries and from a large national payer offering a private insurance (PI) plan and a Medicare Advantage (MA) plan. Potentially preventable hospitalizations were identified using existing definitions for ambulatory care sensitive conditions (ACSCs) and life-limiting malignancies (LLMs).Results: We analyzed 420,369,434 person-years of insurance coverage, during which there were 99,793,416 acute inpatient hospitalizations, of which 16,646,977 (16.7%) were associated with an ICU admission. Of these, the proportions with an ACSC were 12.9%, 12.7%, and 15.8%, and with an LLM were 5.2%, 5.4%, and 6.4%, among those with PI, MA, and FFS, respectively. Over 10 years, the absolute percentages of ACSC-associated ICU stays declined (PI = -1.1%, MA -6.4%, FFS -6.4%; all P < 0.001 for all trends). Smaller changes were noted among LLM-associated ICU stays, declining in the MA cohort (-0.8%) and increasing in the FFS (+0.3%) and PI (+0.2%) populations (P < 0.001 for all trends).Conclusions: An appreciable proportion of U.S. ICU admissions may be preventable with community-based interventions. Investment in the outpatient infrastructure required to prevent these ICU admissions should be considered as a complementary, if not alternative, strategy to expanding ICU capacity to meet future demand.

Keywords: community medicine; critical care; risk factors.

Figures

Figure 1.

Percentage of hospitalizations, stratified by the presence of an intensive care unit (ICU) stay and payer, for each potentially preventable condition. Each bar displays the 95% binomial confidence interval. FFS = Fee-for-Service; MA = Medicare Advantage; PI = private insurance.

Figure 2.

State-level differences in rates of intensive care unit (ICU) admissions for a potentially preventable cause among Medicare Fee-for-Service beneficiaries at least 65 years old adjusted for the age, sex, distribution, and ICU bed capacity in each state, per 100,000 person-years per ICU bed. ACSCs = ambulatory care sensitive conditions; LLMS = life-limiting malignancies.

Figure 3.

Unadjusted temporal trends in potentially preventable hospitalizations with and without an intensive care unit (ICU) admission in the United States. The plot shows the percentage of admissions by insurance coverage for hospitalizations associated with diagnostic codes for ambulatory care–sensitive conditions (top panels) and for life-limiting malignancies (bottom panels).

Figure 4.

Differences by age in percentage of intensive care unit (ICU) admissions for a potentially preventable cause. The proportion of ICU admissions associated with an ambulatory care–sensitive condition increases with age, whereas those with a life-limiting malignancy decreases. These trends are consistent across payer groups. Each bar displays the 95% binomial confidence interval. Brackets indicate a value included in the age interval, whereas parentheses indicate a value excluded from it.