Economic and clinical benefits of early identification of acute kidney injury using a urinary biomarker

Figures & data

Table 1. Model assumptions.

Model input	Base scenario value
	Under SOC	Under SOC and [TIMP-2]·[IGFBP7]
Patients treated in the hospital annually	10,000
Percent of inpatients expected to be assessed for AKI	10%
Adoption rate of [TIMP-2]·[IGFBP7]	50%
Distribution of payer types among tested patients
Percent Medicare or Medicaid	50%
Percent commercially insured	40%
Percent uninsured	10%
Diagnostic efficacy of patients under SOC
No AKI	43%	55%
Mild AKI	39%	39%
Moderate AKI	14%	5%
Severe AKI	4%	1%
ICU bed days
No AKI	1
Mild AKI	2
Moderate AKI	3
Severe AKI	5
Non-ICU, inpatient bed days
No AKI	4
Mild AKI	7
Moderate AKI	8
Severe AKI	11
Percent of patients with 30-day readmissions for any cause
No AKI	9%
Mild AKI	16%
Moderate AKI	22%
Severe AKI	29%
Costs of healthcare resource utilization
Cost per ICU bed day	$5,000
Cost per non-ICU, inpatient bed day	$2,500
Cost per 30-day re-admission	$9,000
Number of [TIMP-2]·[IGFBP7] tests required per patient	2
Per usage estimate for [TIMP-2]·[IGFBP7]	$277

For each level of AKI severity, as well as for patients without AKI, the base-case model assumed no additional treatment costs. Monetary values are in 2017 United States dollars.

Abbreviations. AKI, acute kidney injury; ICU, intensive care unit; SOC, standard of care.

Figure 1. Overview of the economic model. The numbers and percentages are based on base-case assumptions and peer-reviewed literature (Table 1). Abbreviations. AKI, acute kidney injury; SOC, standard of care; Mod, moderate; Sev, severe.

Table 2. Annual net savings by level of AKI severity, overall, and per tested patient.

	No AKI	Mild	Moderate	Severe	Total
Per tested patient	−$1,227	$0	$2,126	$956	$1,578
Overall	−$613,311	$0	$1,063,149	$477,766	$789,104

Total cost is inclusive of the incremental per-usage estimate for [TIMP-2]·[IGFBP7]. Monetary values are in 2017 United States dollars.

Abbreviations. AKI, acute kidney injury.

Table 3. Reduction in overall clinical burden and resulting budget impact by AKI severity, overall and per patient.

	No AKI	Mild	Moderate	Severe	Total
Overall reduction in health care resource utilization among target population
Total ICU bed days under SOC	181	264	146	70	661
Total ICU bed days with SOC and [TIMP-2]·[IGFBP7]	232	264	50	24	570
Decrease in ICU bed days with [TIMP-2]·[IGFBP7]	−51	0	96	46	91
Total non-ICU bed days under SOC	465	775	319	136	1,696
Total non-ICU bed days with SOC and [TIMP-2]·[IGFBP7]	597	775	109	46	1,527
Decrease in non-ICU bed days with [TIMP-2]·[IGFBP7]	−131	0	211	90	170
Resulting budget impact due to reduced uncompensated care among target population
Total ICU costs under SOC	$905,100	$1,322,475	$729,675	$349,590	$3,306,840
Total ICU costs with SOC and [TIMP-2]·[IGFBP7]	$1,160,085	$1,322,475	$248,164	$118,896	$2,849,619
ICU savings with addition of [TIMP-2]·[IGFBP7] to SOC	−$254,985	$0	$481,511	$230,694	$457,221
Total non-ICU costs under SOC	$1,163,700	$1,937,513	$798,413	$341,205	$4,240,830
Total non-ICU costs with SOC and [TIMP-2]·[IGFBP7]	$1,491,538	$1,937,513	$271,541	$116,044	$3,816,636
Non-ICU, inpatient savings with addition of [TIMP-2]·[IGFBP7] to SOC	−$327,838	$0	$526,871	$225,161	$424,194
Total readmission costs under SOC	$108,224	$167,360	$82,993	$33,205	$391,781
Total readmission costs with SOC and [TIMP-2]·[IGFBP7]	$138,713	$167,360	$28,226	$11,293	$345,591
Savings on 30-day readmissions with addition of [TIMP-2]·[IGFBP7] to SOC	−$30,489	$0	$54,767	$21,912	$46,189
Total cost of uncompensated care under SOC	$2,177,024	$3,427,347	$1,611,080	$724,000	$7,939,451
Total cost of uncompensated care with SOC and [TIMP-2]·[IGFBP7]	$2,790,335	$3,427,347	$547,931	$246,233	$7,011,846
Savings on uncompensated care with addition of [TIMP-2]·[IGFBP7] to SOC	−$613,311	$0	$1,063,149	$477,766	$927,604
Per-tested-patient savings on uncompensated care with addition of [TIMP-2]·[IGFBP7] to SOC	−$1,227	$0	$2,126	$956	$1,855

Monetary values are in 2017 United States dollars.

Abbreviations. AKI, acute kidney injury; ICU, intensive care unit; SOC, standard of care.

Figure 2. Results of the deterministic sensitivity analyses. Monetary values are in 2017 US$. Abbreviations. AKI, acute kidney injury; ICU, intensive care unit; SOC, standard of care.

Figure 3. Results of the probabilistic sensitivity analyses. Out of 5,000 iterations, adding [TIMP-2]·[IGFBP7] to SOC resulted in net savings over 99% of the time. Monetary values are in 2017 US$. Abbreviation. SOC, standard of care.