Hospital-acquired Pressure Ulcer Incidence and Variance at U.S. Academic Medical Centers, 2007-2012: tracking changes since CMS nonpayment policy

Objective: Pressure ulcer incidence peaked in the mid-2000s, but since Centers for Medicare and Medicaid Services (CMS) established nonpayment policy for hospital-acquired conditions in 2008, incidence rates may have improved.  Our objective was to define changes in hospital-acquired pressure ulcer (HAPU) incidence and variance since 2008.

Methods: A retrospective observational cohort of U.S. academic medical centers of the University HealthSystem Consortium (UHC) studied hospital inpatients at UHC hospitals at-risk for developing HAPUs. HAPU incidence rates were calculated as a ratio of HAPU cases to total number of at-risk UHC inpatients between 2007-2012.  HAPU cases were defined by multiple criteria: not present-on-admission (POA); coded for stage III or IV pressure ulcers (ICD-9 707.23-707.24); and a length-of-stay greater than 4 days. A t-test measured significant reductions in HAPU incidence post-policy.  An analysis of covariance (ANCOVA) model measured changes in variance of HAPU incidence while controlling for CMS policy and HAPU risk factors.

Results: Among UHC hospitals between 2007-2012, there were 27,289 HAPU cases out of 4.29 million patients considered at-risk.  HAPU incidence dropped significantly from 81 cases per 1,000 inpatients in 2007 to 0.7 cases per 1,000 in 2012 (p<0.001; 95% CI: 0.0236-0.0289).  Among HAPU cases were trends of more elderly patients, greater case-mix index, and more surgical cases. The ANCOVA model identified CMS nonpayment policy as a significant covariate of changing trends in HAPU incidence.

Conclusions:  HAPU incidence has reduced significantly since changes in CMS nonpayment policy.  Hospitals reacted efficiently to economic policy incentives by improving prevention efforts.