Predictors of Cardiopulmonary Hospitalization in Chronic Spinal Cord Injury

Abstract

Waddimba AC, Jain NB, Stolzmann K, Gagnon DR, Burgess JF, Kazis LE, Garshick E. Predictors of cardiopulmonary hospitalization in chronic spinal cord injury.

Objective

To investigate longitudinal risk factors of hospitalization for circulatory and pulmonary diseases among veterans with chronic spinal cord injury (SCI). Circulatory and respiratory system illnesses are leading causes of death in patients with chronic SCI, yet risk factors for related hospitalizations have not been characterized.

Design

Prospective cohort study.

Setting

Veterans Affairs (VA) Boston Healthcare System, Boston, Massachusetts.

Participants/Data Sources

Veterans (N=309) greater than or equal to 1 year post-SCI from the VA Boston Chronic SCI cohort who completed a health questionnaire and underwent spirometry at study entry. Baseline data were linked to 1996 through 2003 hospitalization records from the VA National Patient Care Database.

Interventions

Not applicable.

Main Outcome Measures

Cardiopulmonary hospital admissions, the predictors of which were assessed by multivariate Cox regression.

Results

Of 1478 admissions observed, 143 were a result of cardiopulmonary (77 circulatory and 66 respiratory) illnesses. Independent predictors were greater age (3% increase/y), hypertension, and the lowest body mass index quintile (<22.4kg/m2). A greater percentage-predicted forced expiratory volume in 1 second was associated with reduced risk. SCI level and completeness of injury were not statistically significant after adjusting for these risk factors.

Conclusions

Cardiopulmonary hospitalization risk in persons with chronic SCI is related to greater age and medical factors that, if recognized, may result in strategies for reducing future hospitalizations.

Key Words: Cardiovascular system, Hospitalization, Proportional hazards models, Rehabilitation, Respiratory system, Spinal cord injuries

a Research and Development Service, VA Boston Healthcare System, Boston, MA

b Medical Service/Pulmonary and Critical Care Medicine Section, VA Boston Healthcare System, Boston, MA

c Massachusetts Veterans Epidemiology Research and Information Center, VA Boston Healthcare System, Boston, MA

d Center for Organization, Leadership and Management Research, VA Boston Healthcare System, Boston, MA

e Department of Biostatistics, Boston University Medical Campus, Boston, MA

f Department of Health Policy and Management, Boston University Medical Campus, Boston, MA

g Harvard Medical School, Boston, MA

h Department of Medicine/Channing Laboratory, Brigham and Women's Hospital, Boston, MA

i Spaulding Rehabilitation Hospital, Boston, MA

Correspondence to Eric Garshick, MD, MOH, Associate Chief, Pulmonary and Critical Care Medicine Section, VA Boston Healthcare System, 1400 VFW Parkway, West Roxbury, MA 02132

Supported by the National Institutes of Health/National Institute of Child Health and Human Development (grant no. R01 HD42141; Garshick), and the Office of Research and Development, Health Services Research and Development, and Massachusetts Veterans Epidemiology Research Information Center Cooperative Studies Program, Department of Veterans Affairs.

No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organization with which the authors are associated.

Reprints are not available from the author.

PII: S0003-9993(08)01605-5

doi:10.1016/j.apmr.2008.07.026

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