Predictors of pressure injuries: a multivariate regression analysis of International Pressure Ulcer Prevalence™ Survey data (2011-2016)

Purpose: Limited evidence exists regarding how patient characteristics may increase the risk of developing severe hospital acquired pressure injuries (HAPI), defined as stage III plus. This analysis aimed to understand and compare the relationships between patient demographics and clinical characteristics with the presence of any pressure injury (PI), HAPIs, and severe HAPIs.

Methods: Data from the IPUP’s observational, cross-sectional cohort database was analyzed after IRB exempt determination (Schulmann IRB#201606306). Observations were limited to 2011-2016 US acute care subjects who had complete data within acceptable limits. Three logistic regressions examined associations between patient demographics and clinical characteristics with having any PI, HAPIs, or severe HAPIs.

Results: IPUP data 2011-2016 (n=636,695) were filtered for complete valid data (n=252,784). 26,150 subjects had a PI, 9,498 had a HAPI, and 3,242 had a severe HAPI. The following factors were associated with all three PI categories (p<0.001): age, male gender, longer length of stay (LOS), increased linen layers, and lower Braden scores. Risk of all PI categories increased at both ends of the weight spectrum. All types of incontinence (urinary, fecal, fecal management system, catheter, or an ostomy) were positively associated with the presence of any type of PI and HAPIs [OR range 1.24-2.95, p<0.001]. Incontinence – excluding urinary – was also a significant predictor of severe HAPIs. ICU patients were less likely to have any PI [OR=0.90, p<0.001], but more likely to develop HAPIs [OR=1.37, p<0.001] or severe HAPIs [OR=1.85, p<0.001], controlling for factors above. 

Conclusion: Severe HAPIs lead to longer LOS, greater hospital costs, and higher mortality. We found evidence that hospitals reported fewer HAPIs over time; however, that did not hold for severe HAPIs. Furthermore, we found patients with fecal incontinence were at greater relative risk of developing severe HAPIs [OR=2.22] than any stage HAPIs [OR=1.90], highlighting the importance of managing incontinence.