Skin property can predict the development of skin tears among elderly patients: a prospective cohort study

The aim of this study was to identify skin properties that may be used to predict the development of a skin tear (ST) among elderly patients. A prospective cohort study was conducted among elderly patients aged 65 and older (N = 149) at a long-term medical facility in Japan over an 8-month period. Skin properties at baseline were measured on the forearm using a 20-MHz ultrasound scanner, which measured the thickness of the dermis layer and low-echogenic pixels, and skin blotting method, which evaluated the levels of collagen type IV, matrix metalloproteinase-2 and tumour necrosis factor-alpha. Adjusted hazard ratios (HRs) for the main confounders were obtained using the Cox proportional hazard model. A total of 52 STs were recorded among the 21 patients, resulting in an incidence rate of 1·13/1000 person-days. The predictor of STs was dermis thickness (HR = 0·52; 95% confidence interval = 0·33–0·81; P-value = 0·004). The cut-off point for dermis thickness was 0·80 mm (area under the curve = 0·77; 95% confidence interval = 0·66–0·88; P-value = 0·006). Our results suggest that measuring the dermis thickness at baseline is an easy and accurate way to identify a high-risk patient.