An evidence-based review of aging of the body systems following spinal cord injury

Abstract
Systematic review. To systematically review evidence on aging of the body systems after spinal cord injury (SCI). Toronto, Ontario and Vancouver, British Columbia, Canada. Electronic databases (MEDLINE/PubMed, CINAHL, EMBASE and PsycINFO), were searched for studies published between 1980 and 2009. The search was augmented by reviewing the reference lists of relevant papers. Non-intervention studies that were longitudinal or cross-sectional with able-bodied controls that were at minimum matched on chronological age were included for review. Levels of evidence were assigned to the study design using a modified Sackett scale. Of the 74 studies selected for inclusion, 16 were longitudinal in design. The hypothesis that SCI represents a model for premature aging is supported by a large proportion of level 5 evidence for the cardiovascular and endocrine systems, level 2, 4 and 5 evidence for the musculoskeletal system, and limited level 5 evidence for the immune system. Only a few level 4 and 5 studies for the respiratory system were found. The evidence on the genitourinary system, gastrointestinal system, and for skin and subcutaneous tissues provide level 4 and 5 evidence that premature aging may not be occurring. The evidence on the nervous system does not provide evidence of premature aging as a result of SCI. Premature aging appears to occur in some systems after SCI. Additional longitudinal studies are required to confirm these findings. Rick Hansen Institute; Ontario Neurotrauma Foundation.