ICU Admission Reduces Survival, Augments Costs Among Patients With AML

A study published by researchers from the Fred Hutchinson Cancer Research Center in Seattle has found that admission to the intensive care unit (ICU) reduced survival and increased the cost of care among patients undergoing treatment for acute myeloid leukemia (AML).

A disease with dismal outcomes, about 75% of patients diagnosed with AML do not survive for more than 5 years. With the objective of examining the risk factors, mortality, length of stay (LOS), and cost associated with admission to the ICU for patients with AML, scientists at Fred Hutch extracted data from the University HealthSystem Consortium database on adult patients diagnosed with AML and who were hospitalized between January 1, 2004, and December 21, 2012. The primary outcomes being evaluated were admission to the ICU and inpatient mortality among patients who needed ICU care. Secondary outcomes included LOS in ICU, total LOS, and cost.

During the study period, a little more than 25% (11,277) of patients diagnosed with AML were admitted to the ICU. Risk factors for admissions included:

• Younger than 80 years old (odds ratio [OR], 1.56; 95% CI, 1.42-1.70)
• Hospitalization in the South (OR, 1.81; 95% CI, 1.71-1.92)
• Hospitalization at a low- or medium-volume hospital (OR, 1.25; 95% CI, 1.19-1.31)
• Number of comorbidities (OR, 10.64; 95% CI, 8.89-12.62, for 5 vs none)
• Sepsis (OR, 4.61; 95% CI, 4.34-4.89)
• Invasive fungal infection (OR, 1.24; 95% CI, 1.11-1.39)
• Pneumonia (OR, 1.73; 95% CI, 1.63-1.82)

In-hospital mortality was significantly greater in patients who needed ICU care (4857 of 11,277 [43.1%] vs 2959 of 31,972 [9.3%]). The authors identified the following risk factors for death in the ICU-admitted cohort:

• Older than 60 years (OR, 1.16; 95% CI, 1.06-1.26)
• Ethnicity (nonwhite) (OR, 1.18; 95% CI, 1.07-1.30)
• Hospitalization on the West Coast (OR, 1.19; 95% CI, 1.06-1.34)
• Number of comorbidities (OR, 18.76; 95% CI, 13.7-25.67, for 5 versus none)
• Sepsis (OR, 2.94; 95% CI, 2.70-3.21)
• Invasive fungal infection (OR, 1.20; 95% CI, 1.02-1.42)
• Pneumonia (OR, 1.13; 95% CI, 1.04-1.24)

Simultaneous with the increased ICU admission was the increased cost of care—patients who needed the intensive care treatment incurred nearly double the cost of those who were not in the ICU ($83,354 versus $41,973, respectively). Presence of comorbidities further accentuated treatment costs, from $50,543 for no comorbidities, all the way to $124,820 in patients with at least 5 comorbidities.

The authors conclude that while comorbidities increase the risk of mortality and cost of care in patients with AML, appropriate interventions by identifying patients at high risk for ICU use could reduce fatalities.

Reference

Halpen AB, Culakova E, Walter RB, Lyman GH. Association of risk factors, mortality, and care costs of adults with Acute Myeloid Leukemia with admission to the intensive care unit [published online November 10, 2016]. JAMA Oncol. doi: 10.1001/jamaoncol.2016.4858.