Hospital-Acquired Pressure Ulcers

Results From the National Medicare Patient Safety Monitoring System Study

Courtney H. Lyder, ND; Yun Wang, PhD; Mark Metersky, MD; Maureen Curry, MHA; Rebecca Kliman, MPH; Nancy R. Verzier, MSN; David R. Hunt, MD


J Am Geriatr Soc. 2012;60(9):1603-1608. 

In This Article


Participant Characteristics

Fifty-one thousand eight hundred forty-two discharges were included in the final study sample for the combined years 2006 and 2007 (Table 1). The HAPU incidence rate was determined to be 4.5% (2,313/51,842), and PU prevalence on admission was 5.8% (2,999/51,842). Of the 2,999 individuals who entered the hospital with a PU, 16.7% (502/2,999) developed at least one new PU at a different location during their hospitalization. The majority of participants who developed at least one PU were nonwhite and aged 75 to 84. These participants had significantly higher rates of CHF, COPD, CVD, diabetes mellitus, and use of corticosteroids during hospitalization. Obesity was significantly associated with HAPUs (Table 1).

The majority of HAPUs were located on the coccyx or sacrum (41%), followed by the hip and buttock region (23%) and the heels (23%). The stages of HAPUs could not be determined because of the wide variability in documentation of description and staging by clinicians. Participant characteristic such as age, diagnosis (cancer, CHF, COPD, CVD, diabetes mellitus), and presence of obesity were all significantly associated with HAPUs (P < .001; Table 2).

Overall, the nationwide HAPU incidence rate was 4.5% (95% CI = 4.1–4.7%). Variance across the nation was statistically significant (Figure 1). The between-state variance was 3.2% (standard error 1.2%), the weighted rates drawn from HGLM ranged from 3.1% (95% CI = 2.5–4.1%) to 5.9% (95% CI = 5.1–7.0%). The odds of developing PUs if treated in a state 1 standard deviation (SD) above the national average relative to the odds of developing PUs if treated at a state 1 SD below the national average were 1.43. Higher incidence rates were noted in the Northeast and Missouri. The five states with the lowest HAPU rates were Wisconsin (3.1%), Alabama (3.3%), Tennessee (3.7%), Puerto Rico (3.7%), and North Carolina (3.8%), and the five states with the highest HAPU rates were New York (5.2%), Missouri (5.3%), New Jersey (5.3%), Massachusetts (5.5%) and Pennsylvania (5.9%). Rates in Wisconsin and Alabama were statistically significantly lower than the national average.

Figure 1.

Pressure ulcer incidence rates according to Centers for Medicare and Medicaid Services Regional Map.

Mortality, Readmission, and Length of Stay

The mortality data revealed that the development of HAPUs was significantly associated with higher in-hospital mortality (11.2%) and mortality within 30 days after discharge (15.3%). HGLMs were fitted to further understand the association between the development of new HAPUs and hospital outcomes (Table 3), mortality and hospital length of stay (Table 4). Participants with HAPUs were significantly more likely to be readmitted within 30 days after discharge (odds ratio (OR) = 1.33, 95% CI = 1.23–1.45), and were more likely to have died in the hospital. The risk-adjusted ORs were 2.81 (95% CI = 2.44–3.23) for in-hospital mortality and 1.69 (95% CI = 1.61–1.77) for mortality within 30 days after discharge. Participants who developed HAPUs had significantly longer hospital lengths of stay (11.6 ± 10.1 days) than those without (4.9 ± 5.2 days).