OBJECTIVE: To identify markers associated with pressure injury (PrI) history in individuals with spinal cord injury (SCI) using two approaches: skin blood flow (SBF) response toward localized heating, and serum marker for insulin resistance. METHODS: For this cross-sectional, observational study of adults with chronic traumatic SCI at T12 and above, researchers recruited two groups of participants: with history of PrI (group 1), and without history of PrI (group 2). The study protocol included obtaining fasting blood samples and measurement of SBF at bilateral heels with localized heating of 42 °C for 30 minutes from all participants. Primary SBF outcomes were initial peak and plateau SBF normalized to baseline SBF. The primary outcome for insulin resistance was Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), calculated from fasting plasma glucose and insulin. Secondary outcomes included demographic and SCI information. Researchers used the Fisher exact test and Wilcoxon-Mann-Whitney test to compare the intergroup difference of categorical and continuous variables, respectively. RESULTS: Sixteen adults completed this study (group 1, n = 7
group 2, n = 9). In comparison with group 2, group 1 had significantly higher HOMA-IR (3.90 ± 0.71 vs 1.45 ± 0.71), suggesting higher insulin resistance, and longer duration of injury (22.54 ± 7.24 vs 7.98 ± 6.58 years). There were no between-group differences in SBF or other secondary outcomes. CONCLUSIONS: HOMA-IR is a novel serum index associated with PrI history in persons with chronic SCI. Future longitudinal study is warranted to examine the role of insulin resistance in increasing PrI risk for the SCI population.