An official American Thoracic Society systematic review: the association between health insurance status and access, care delivery, and outcomes for patients who are critically ill

Abstract

Rationale: One in three Americans under 65 years of age does not have health insurance during some portion of each year. Patients who are critically ill and lack health insurance may be at particularly high risk of morbidity and mortality due to the high cost of intensive care.

Objectives: To systematically review the medical and nonmedical literature to determine whether differences in critical care access, delivery, and outcomes are associated with health insurance status.

Methods: Nine electronic databases (inception to 11 April 2008) were independently screened and abstracted in duplicate.

Measurements and main results: From 5,508 citations, 29 observational studies met eligibility criteria. Among the general U.S. population, patients who were uninsured were less likely to receive critical care services than those with insurance (odds ratio [OR], 0.56; 95% confidence interval [CI], 0.55-0.56). Once admitted to the intensive care unit, patients who were uninsured had 8.5% (95% CI, 6.0-11.1) fewer procedures, were more likely to experience hospital discharge delays (OR 4.51; 95% CI, 1.46-13.93), and were more likely to have life support withdrawn (OR 2.80; 95% CI, 1.12-7.02). Lack of insurance may confer an independent risk of death for patients who are critically ill (OR 1.16; 95% CI, 1.01-1.33). Patients in managed care systems had 14.3% (95% CI, 11.5-17.2) fewer procedures in intensive care, but were also less likely to receive "potentially ineffective" care. Differences in unmeasured confounding factors may contribute to these findings.

Conclusions: Patients in the United States who are critically ill and do not have health insurance receive fewer critical care services and may experience worse clinical outcomes. Improving preexisting health care coverage, as opposed to solely delivering more critical care services, may be one mechanism to reduce such disparities.

Figure 1.

Study selection. *Reasons for exclusion: no comparator groups (n = 18); patients not critically ill (n = 11); study design not eligible (n = 3); outcomes of interest not reported (n = 4); duplicate data from other included study (n = 2); not adult patients (n = 1).

Figure 2.

Admission rate to intensive care unit (ICU) for uninsured versus insured patients presenting to hospital. (a) Unadjusted rates of admission to ICU. (b) Adjusted rates of admission to ICU.

Figure 3.

Hospital mortality rates for uninsured versus insured critically ill patients. (a) Unadjusted mortality rates. (b) Adjusted mortality rates.

Figure 4.

Intensive care unit (ICU) length of stay for patients who are critically ill with managed versus nonmanaged care. (a) Adjusted ICU length of stay (days). (b) Adjusted hospital length of stay (days).

Figure 5.

Hospital mortality rates for patients who are critically ill with managed versus nonmanaged care. (a) Unadjusted mortality rates. (b) Adjusted mortality rates.