Advances in medical technology and therapies over the past 50 years have contributed to increasing life expectancy for the general U.S. population. In fact, with better lifestyles and medical care, people are living longer despite the growing number of chronic medical conditions in our population. According to USA Today, two-thirds of Americans older than 65 years of age have multiple chronic conditions but enjoy much longer life expectancy than those in prior decades. Can the same be said about the spinal cord injury (SCI) population?

Fortunately, we have help answering that question from the National Spinal Cord Injury Statistical Center that maintains the largest set of SCI data available. The center combines 14 spinal cord injury model systems in the U.S. A number of recent research articles investigating the trends of mortality rates and life expectancies in SCI have drawn from this robust data source.

Short-Term Survival

Medical advances in pre-hospital care, such as EMS response and retrieval systems, trauma system development, intensive care units and acute rehabilitation management, have all contributed to significant improvement in acute survival rates for SCI over the past 30 years. A 2006 study by Strauss et al. demonstrated that SCI survival during the first two years post-injury was 39% higher in the period 1990-2004 as compared to 1973-1979.¹ The bottom line is people with SCI are surviving more, even those with more severe injuries, such as tetraplegia. Even those needing mechanical ventilation for respiration are able to recuperate with modern day medical care.

Long-Term Survival & Life Expectancy

Contrary to short-term survival, studies including the Strauss et al. report did not find any trend toward improved long-term survival in SCI populations over the past decades. In fact, a more recent publication by Shavelle et al. this year showed no significant change in mortality rate when comparing the most recent period 2005-2012 to the reference period of 1973-1979. Surprisingly, the research article demonstrated that the mortality rate’s odds ratio (OR), or odds of mortality, in 2005-2012 actually increased slightly from the 1973 -1979 and 1990-2004 periods.²

The inference here is since the life expectancy in the general population has increased over time and SCI long-term mortality rate in general has stayed constant, the life expectancy of SCI population has actually decreased as a percentage of normal life expectancy over the past 30 years. As noted in a research article published in 2015 by Shavelle et al., the standardized mortality ratio (SMR) for persons with SCI in fact increased over the study period at a rate of 2.4% per calendar year. This underscores the important premise that the percentage of normal life expectancy for SCI from past tables may not be applicable today or in the future, and it will require due diligence to using updated tables with refreshed SMR data when it comes to life expectancy calculations.

Causes of Mortality in SCI

 A presentation by DeVivo et al. on causes of death in the SCI population over the past decades sheds some insights as to the growing gap between the SCI and general populations regarding life expectancy. Although there has been good progress in reducing age-adjusted mortality rates from cancer, cardiovascular diseases, pulmonary embolism and stroke, there has been an increase in age-adjusted mortality rates for endocrine (e.g. diabetes), nutritional, metabolic diseases and accidental drug overdoses, mental disorders including alcohol and/or drug use and musculoskeletal disorders including osteomyelitis. More surprising is that mortality rates have not changed for infective diseases such as septicemia and pneumonia or for nervous system disorders since 1980.³

Improving Outcomes

It can be presumed that life expectancy of the SCI population will not improve significantly until progress can be made in reducing mortality rates associated with complications from infection, respiratory issues, endocrine diseases, accidents and mental disorders. But, with greater acute survival of injured workers, it is both crucial and necessary to ensure a systematic care management^SM approach to managing SCI cases.

An effective program should include well-established, comprehensive and regular systems of review with heightened vigilance given to monitoring, education, timely interventions and effective communication. Care managers need to work with treating providers and injured workers to address respiratory and skin issues, infection prevention, health maintenance and psychosocial-behavioral issues to mitigate health complications and improve quality of life.

About the Author

Michael Choo, M.D. is Paradigm’s Chief Medical Officer. He maintains the company’s relationships with its network of consulting physicians and centers of excellence and is responsible for enhancing clinical operations through clinical analytics, as well as leading research and development. He is a member of the clinical faculty at Boonshoft School of Medicine at Wright State University teaching emergency medicine, internal medicine and family practice residents.

Endnotes

¹ Strauss, DeVivo, Paculdo. Trends in life expectancy after spinal cord injury. Archives of Physical Medicine and Rehabilitation 2006; 87: 1079-85

² Shavelle, DeVivo, Brooks, Strauss, Paculdo. Improvements in long-term survival after spinal cord injury? Archives of Physical Medicine and Rehabilitation 2015; 96: 645-51

³ DeVivo, Chen, Krause, Saunders. Causes of Death in an Aging SCI population presentation. University of Alabama. Department of Physical Medicine & Rehabilitation. 2013