Rohan Mahabaleshwarkar, MS; Rahul Khanna, MBA, Ph.D.

Department of Pharmacy Administration, The University of Mississippi

NATIONAL HOSPITALIZATION BURDEN ASSOCIATED WITH SPINAL CORD INJURIES

METHODS

OBJECTIVES

CONCLUSIONS

• To compare patient, hospital, and discharge level characteristics

among patients with SCI to those without SCI (control group).

• To identify factors predicting length of stay (LOS), total charges, and

mortality among patients with SCI.

• To identify common procedures performed during SCI hospitalizations.

Data Source

• The 2009 Health Care Utilization Project Nationwide Inpatient Sample

(HCUP – NIS) data was used for the purpose of the study.

Study Design

• A retrospective cross-sectional case-control study design was used.

• Hospitalizations with LOS > 365 days or total charges > $ 1 million and

pediatric hospitalizations (age<18 years) were excluded from the study.

• Cases were identified as records with a primary diagnosis of SCI (ICD-

9-CM code 806.xx and 952.xx).

Analysis

• Each case was matched to two controls based on age and gender

using a greedy match algorithm.

• Chi-square (PROC SURVEYFREQ) and linear regression (PROC

SURVEYREG) were used to compare characteristics of

hospitalizations among patients with SCI to the characteristics of

hospitalizations among control group.

• Linear regression (PROC SURVEYREG) was used for determining

factors predicting total charges, whereas logistic regression (PROC

SURVEYLOGISTIC) was used to determine factors predicting

mortality.

BACKGROUND

• Spinal cord injury (SCI) refers to the acute traumatic lesion of the

nervous elements in the spinal cord or cauda equina leading to loss in

the functions of the nervous system.1

• The incidence of SCIs in the United States (US) has been estimated

to be around 12,000 cases per year.1

• SCIs pose a significant economic burden. The total annual costs

attributable to SCIs are approximately $9.7 billion in the US.2,3

• A SCI is a medical emergency. Nearly all SCI patients, who survive

the initial trauma, undergo hospitalization.4

• The true hospitalization burden among patients with SCI is currently

unknown.

POSTER PSU37 - ISPOR 17th ANNUAL INTERNATIONAL MEETING JUNE, 2012

RESULTS

REFERENCES

RESULTS

• In 2009, there were 11,848 hospitalizations associated with SCI in

the US (Table 1).

• In comparison to patients in the control group, those with SCI had

higher LOS (~ 2.5 times), mortality rate (~ 1.3 times), and total

hospitalization charges (~ 4 times).

• Age (patients < 60 years), region of the hospital (west vs. south),

primary payer (private insurance vs. self pay), hospital size (large vs.

small) , hospital location (rural vs. urban), discharge disposition

(other facilities vs. routine), higher number of diagnoses on the

record and higher LOS were associated with higher total

hospitalization charges.

• Age (patients ≥ 60 years), gender (male vs. female), primary payer

(private insurance vs. self pay), and higher number of diagnoses on

the record, were associated with increased likelihood of mortality

among patients with SCI.

• The most common procedures performed on patients with SCI were

spinal refusion, operations on the spine, plastic operations on the

spinal cord, excision of bone for graft, and implantation of other

musculoskeletal devices and substances.

• The total economic burden of SCI-related hospitalizations was

~ $1.7 billion in 2009.

• Inpatient costs, LOS, and mortality were significantly higher among

individuals with SCI as compared to those without SCI.

• Patient, hospital and discharge level characteristics predicted

outcomes of SCI-related hospitalizations.

• Policy makers can use these findings for efficient and rational

resource allocation to better serve the needs of patients with SCI.

1. National Spinal Cord Injury Statistical Center. Available at:

https://www.nscisc.uab.edu/public_content/nscisc_database/definition_eligibility.aspx.

Accessed November 02, 2011.

2. Berkowitz M, O’Leary PK, Kruse DL, Harvey C. Spinal Cord Injury: An Analysis of Medical and

Social Costs. New York: Demos Medical Publishing, 1998.

3. French DD, Campbell RR, Sabharwal S, Nelson AL, Palacios PA, Gavin-Dreschnack D. Health

care costs for patients with chronic spinal cord injury in the Veterans Health Administration. J

Spinal Cord Med 2007;30:477-481.

4. Buechner JS, Speare MC, Fontes J. Hospitalizations for spinal cord injuries, 1994-1998. Med

Health R I 2000;83:92-93.

Table 1. Characteristics of the study samplea

Variable Patients with

SCI

Patients

without SCI P

Patient characteristics Age (Years)

18 – 29 1,998 (16.9) 4,061 (16.9)

30 – 39 1,345(11.4) 2,773 (11.5)

40 – 49 1,789 (15.1) 3,661(15.2)

50 – 59 2,152 (18.2) 4,365 (18.2)

≥60 4,563 (38.5) 9,186 (38.2)

Gender

Female 3,610 (30.5) 7,337 (30.5)

Male 8,238 (69.5) 16,708 (69.5)

Median household income

$0-$38,999 3,025 (26.7) 6,630 (28.8) 0.5857

$39,000-$47,999 3,217(28.4) 6,167 (26.8)

$48,000-$62,999 2,760(24.4) 5,683 (24.7)

≥$63,000 2,321 (20.5) 4,547 (19.8)

Primary payer

Public 5,129 (43.3) 12,554 (52.3) <0.0001

Private insurance 4,518 (38.1) 7,765 (32.3)

Other 1,202 (10.1) 2,254 (9.4)

Self pay 999 (8.4) 1,467 (6.1)

Hospital characteristics Region of hospital

Northeast 2,408 (20.3) 4,981(20.8) 0.7646

Midwest 2,630 (22.2) 5,630 (23.5)

West 4,294(36.2) 8,988 (37.4)

South 2,516(21.2) 4,437 (18.5)

Hospital size

Large 427 (3.7) 2,598 (10.9) <0.0001

Medium 2,754 (22.5) 5,540 (23.44)

Small 8,448 (73.8) 15,503 (66.57)

Location of hospital

Rural 496 (4.3) 2,706 (11.45) 0.0009

Urban 19,953 (95.7) 20,935 (88.55)

Teaching status of hospital

Nonteaching 2,875 (25.1) 12,365 (52.3) <0.0001

Teaching 8,574 (74.9) 11,277 (42.7)

Discharge characteristics Discharge disposition, n

(%)

Routine 3,257 (27.5) 16,924 (70.4) < 0.0001

Died 682 (5.8) 544 (2.3)

Otherb 7,909 (66.8) 6,578 (27.4)

Length of stay , mean (SE) 12.37 (0.5) 4.93 (0.1) < 0.0001

Total charges, mean (SE) 142,366

(7,430.5)

35,011

(1,048.9) < 0.0001

Number of procedures on

this record, mean (SE) 4.84 (0.2) 1.66 (0.0) < 0.0001

Total hospitalizations 11,848 24,046

aAll estimates are weighted. bThe category “Other” consisted of transfer to short-term hospital, transfer to other facility, home

health care, against medical advice, and discharged alive to unknown destination.

Table 2. Predictors of total charges and mortality for

hospitalizations associated with spinal cord injury Variable βb P Odds ratioc P

Age (Years)

18 – 29 57,851.55 <0.0001 0.163 <0.0001

30 – 39 50,272.11 <0.0001 0.284 0.0025

40 – 49 41,267.34 <0.0001 0.231 0.0002

50 – 59 23,531.01 0.0035 0.314 0.0004

≥ 60 Ref Ref

Gender

Female -4,896.19 0.3273 1.571 0.0381

Male Ref Ref

Median household income

$0-$38,999 -9,355.13 0.4358 1.245 0.5221

$39,000-$47,999 -6,548.50 0.4239 1.129 0.6704

$48,000-$62,999 -5,065.29 0.5239 0.851 0.6006

≥ $63,000 Ref Ref

Region of hospital

Northeast 31,114.60 0.1741 1.320 0.3864

Midwest 13,635.78 0.2468 0.784 0.3591

West 76,210.58 <0.0001 1.136 0.6788

South Ref Ref

Primary payer

Public 14,543.13 0.1882 0.650 0.2353

Private insurance 25,161.13 0.0045 0.447 0.0246

Other 22,565.04 0.1066 0.653 0.3422

Self pay Ref Ref

Hospital size

Large 36,634.39 0.0188 1.388 0.5618

Medium 37,786.85 0.0372 1.939 0.2580

Small Ref Ref

Location of hospital

Rural 35,962.52 0.0044 0.513 0.2348

Urban Ref Ref

Teaching status of hospital

Nonteaching 20,695.24 0.0610 0.660 0.1839

Teaching Ref Ref

Discharge dispositiond

Died 36,015.18 0.0124 - -

Other 41,322.47 <0.0001 -

Routine Ref -

Number of diagnoses on the

record 5,276.40 <0.0001 1.085 0.0006

Length of stay 5,627.05 <0.0001 0.987 0.4364

aAll estimates are weighted. bObtained from the multiple regression analysis conducted to determine the predictors of the

total charges for SCI-related hospitalizations. cObtained from logistic regression analysis conducted to determine the predictors of in-hospital

mortality among patients with SCI. dDischarge disposition was collapsed into three categories: died, other and routine.

Author’s Contact: rkmahaba@olemiss.edu