Date Presented 4/1/2017
We tested an occupational therapy intervention designed to prevent medically serious pressure ulcers (MSPrUs) in 232 adults with spinal cord injury. MSPrU rates did not differ between the intervention and control groups. The intractable nature of the ulcer threat and lack of power may have contributed to the null result.
Primary Author and Speaker: Florence Clark
Contributing Authors: Jeanine Blanchard, Cheryl Vigen, Michael Carlson
PURPOSE: Medically serious pressure ulcers (MSPrUs), a common complication of spinal cord injury (SCI; National Spinal Cord Injury Statistical Center, 2005), have devastating consequences on health and well-being and are extremely expensive to treat (DeVivo & Farris, 2011). We aimed to test the efficacy of a lifestyle-based intervention designed to reduce incidence of MSPrUs in adults with SCI as part of the University of Southern California–Rancho Los Amigos National Rehabilitation Center (RLANRC) Pressure Ulcer Prevention Study.
DESIGN: This study was a randomized controlled trial (RCT) of a 1-yr intervention with 1 additional year of follow-up and a separate study wing involving a nonrandomized standard-care control group followed for 1 yr.
METHOD: Recruitment and ongoing medical treatment were undertaken at RLANRC, a large facility serving ethnically diverse, low-income residents of Los Angeles County. Adults with SCI who had one or more prior MSPrUs over the past 2 yr (n = 387) were assessed for eligibility, and 170 were enrolled for the RCT component. No participants withdrew due to adverse effects, and 166 (98%) were evaluable for the primary outcome (85% male, 50% Hispanic). The nonrandomized control group included 66 participants. The Pressure Ulcer Prevention Program, a 12-mo lifestyle-based intervention, was administered by occupational therapists in consultation with registered nurses, largely via in-home visits and phone contacts.
Main outcome measures included annualized MSPrU incidence rates at 12 and 24 mo based on skin checks, quarterly phone interviews with participants, and review of medical charts and billing records. Secondary outcomes included number of surgeries and various quality of life measures. Supplementary analyses included identifying risk factors for development of one or more MSPrUs during the study period, and latent class analyses of participants who incurred MSPrUs and those who did not. Observers were blinded to patient groupings for all assessments.
RESULTS: Annualized MSPrU rates did not differ significantly between study groups at either 12 or 24 mo. We sought a 50% reduction in MSPrU rate in the intervention compared with the randomized control group. The Year 1 MSPrU rate was 0.48 per person per year for randomized control participants. The 12-mo rate ratios compared with randomized control were 1.15 (95% confidence interval [CI] [0.76, 1.76]) for the intervention and 1.34 (95% CI [0.87, 2.07]) for the nonrandomized groups. Previous pressure ulcers (odds ratio [OR] = 6.1, p < .001), diabetes (OR = 2.4, p = .01), and other comorbidities (OR = 1.8, p = .03) were associated with 12-mo incidence of MSPrUs. Over the course of the intervention, quality of life measures improved in both the intervention and control groups, but the differences between groups were not statistically significant.
CONCLUSION: The null result for the intent-to-treat analysis is inconclusive, largely because of the much lower than anticipated annualized MSPrU rate in the sample, which decreased statistical power. However, other factors may have contributed to the findings, such as the intractable nature of the ulcer threat and the social determinants of health that impacted this particular largely socioeconomically disadvantaged subset of the SCI population. Caution should be exercised in attempting to apply the results to more typical SCI populations. We feel that it is important to continue this type of intervention research, despite the difficulties involved, in light of the tremendous potential to enhance the lives of individuals with SCI. Future research studies should give careful consideration to individual participant characteristics that may influence the efficacy of the intervention in total or the features of the intervention that best serve different individuals. Creative solutions to statistical power limitations and outcome measurement should be explored.
References
DeVivo, M., & Farris, V. (2011). Causes and costs of unplanned hospitalizations among persons with spinal cord injury. Topics in Spinal Cord Injury Rehabilitation, 16, 53–61. https://doi.org/10.1310/sci1604-53
National Spinal Cord Injury Statistical Center. (2005). The 2005 annual statistical report for the Model Spinal Cord Injury Care Systems. Birmingham, AL: Author.
