Cost-Effectiveness of Early Discharge After Uncomplicated Acute Myocardial Infarction

abstract & commentary

Synopsis: A cost analysis for hospitalizing patients with uncomplicated acute myocardial infarction beyond three days after thrombolysis has an estimated cost of $105,629 per year of life saved and is economically unattractive by current standards.

Source: Newby LK, et al. N Engl J Med 2000;342:749-755.

Newby and associates noted that previous investigators have suggested the feasibility and safety of discharging patients as early as three days after infarction. In the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries-1 (GUSTO-1) study that looked at four thrombolytic treatment groups, the mortality for patients without cardiac complications had 30-day mortality rates of 1%. Since the mortality rates for uncomplicated infarctions is low, Newby et al decided to assess the cost effectiveness of discharging patients 72 hours after thrombolysis in patients with uncomplicated myocardial infarction (MI).

The study group consisted of the 41,021 patients who participated in GUSTO-1. Approximately 22,000 individuals had an uncomplicated course, defined as no mortality or serious cardiovascular events and discharge after 96 hours. Newby et al used a decision analysis to estimate the cost per year of life saved if patients with an uncomplicated course were discharged at 72 hours instead of after four days. They determined the number of treatable ventricular arrhythmias after day 3 and assumed that these patients would have died if they were discharged. The primary costs considered were the costs associated with an additional hospital day. Costs for lab testing was assumed to be similar for both the inpatient and outpatient setting. The model assumed that all inpatient deaths from arrhythmia were untreatable and that discharged patients had ready access for care of complications. Newby et al specifically noted that their analysis applied only to patients with uncomplicated thrombolysis and not to other types of patients such as those undergoing bypass graft surgery or angioplasty.

The rate of ventricular arrythmias for all GUSTO-1 participants dropped dramatically after 48 hours. After 72 hours, there were only 16 serious arrythmias among the approximately 22,000 patients with uncomplicated courses at day 3. Three of these patients died. Newby et al conclude that hospitalizing a patient with an uncomplicated course cost an average of $105,629 per year of life saved. The sensitivity analysis estimated that costs ranged from $65,777 per year of life saved to $183,524. They also note that risk stratification to identify those most at risk for an arrhythmia and keeping these individuals for 96 hours may also be a cost effective method.

Comment by martin lipsky, md

This study showed that in the described setting, hospitalizing patients after an uncomplicated course following thrombolysis is unattractive by the conventionally accepted economic threshold of $50,000 per year of life saved. However, for those of us in primary care, it is clear that an additional day of hospitalization may offer significant benefits that were not studied. A cardiac event is a catastrophic event and an extra day in the hospital setting might have an important effect on quality of life and preparing family members to have the patient return home. In addition, an extra day might be used for intensive education about lifestyle issues such as diet and exercise that might offer a long-term advantage over early discharge. Also, when we know that so many individuals with heart disease do not receive such widely accepted treatments as aspirin, beta-blockers, and ace inhibitors, I wonder if earlier discharges might not reduce patient adherence and having these medicines prescribed before discharge. Despite these concerns, I agree that this thoughtful analysis shows that an extra day of hospitalization may not be cost beneficial. However, I would like to see confirmation of these findings and also perhaps a risk stratification plan before making this standard treatment.