Objective: To examine the relationship between a measure of skin and tissue water, subepidermal moisture (SEM), and visual assessment of early pressure ulcer (PU) damage in nursing home (NH) residents with dark skin tones.
Design, setting, and participants: Descriptive, cohort study with 66 residents in 4 US NH.
Methods: Data were pooled from 2 previous NH studies to evaluate persons with dark skin tones. Data were analyzed for concurrent visual assessments and SEM, which were obtained at the right and left buttocks and sacrum weekly for 20 weeks. Subepidermal moisture was measured with a surface electrical capacitance dermal phase meter, where higher readings indicate greater SEM (range: 0-999 dermal phase units [DPUs]). Visual assessment was rated as normal, erythema/stage I PU, or stage II+ PU. Subepidermal moisture and specific SEM threshold values (50, 150, 300 DPU) were modeled as detectors of visual assessment of early PU 1 week later (controlling for clustering and incontinence); with concurrent SEM, and PU risk status, in separate analyses for persons with light and dark skin tones.
Results: Participants had a mean age of 84 years, 83% were female, and 77% were non-Hispanic white. Higher SEM predicted greater likelihood of erythema/stage I PU and stage II+ PU in persons with dark skin tones the next week (OR = 1.88 for every 100 DPU increase in SEM, P = .004). When SEM was greater than 50, 150, and 300 DPU, persons with dark skin tones were 8.5, 13, and 10 times more likely to present with stage II+ PU the following week compared to persons with light skin who were 7.2, 3.5, and 4.3 times more likely to present with stage II PU (50, 150, 300 DPU, respectively). Subepidermal moisture threshold of 50 DPU was also significant for detecting erythema/stage I PU in persons with dark skin tones (OR = 5.3, 95% CI, 1.87-15.11, P < .001).
Conclusions: Subepidermal moisture was associated with future (1 week later) PU in persons with dark skin tones. Subepidermal moisture threshold values may assist in detecting early PU in persons with dark skin tones, allowing for earlier intervention to prevent PU. These findings should be further evaluated in persons with dark skin tones.