1. National Pressure Ulcer Advisory Panel Board of Directors

Article Content

The State of Pressure Ulcers in the United States, 1990-2000

In 1989, the National Pressure Ulcer Advisory Panel (NPUAP) set a national goal for the ensuing decade of reducing the incidence of pressure ulcers by 50%.1 To reach this goal, NPUAP has promoted an active program that aimed to improve clinical practice on pressure ulcers through education, research, and public policy. Now, a decade later, it is important to survey the state of pressure ulcers in the United States and determine whether the goal was achieved. To accomplish this, the NPUAP has conducted a comprehensive review of the incidence and prevalence data published over the last decade.


Literature Review Methods

A Medline database search for all articles published and indexed between January 1, 1990 and June 1, 2000 (and later updated through December 31, 2000) yielded over 300 studies on pressure ulcer incidence and prevalence. Pressure ulcer incidence and prevalence data were analyzed across care settings (acute care-including critical care and the operating room, long term care, rehabilitation facilities, and home care) and in specific populations such as individuals with spinal cord injuries, the elderly, infants and children, patients with hip fractures, persons of color, and those at the end of life receiving palliative or hospice care.



Whereas many positive developments have occurred over the past decade in the prevention and treatment of pressure ulcers, their impact on pressure ulcer rates remains uncertain. The data published in the literature are inconsistent due to differences in methodologies used and populations studied. These differences make comparisons and analyses of definitive trends difficult.


Incidence data reported over the last decade are summarized on Table 1 and Figures 1 and 2. The wide variations in the range of incidence rates (i.e., general acute care, 0.4 to 38%;2,3 long term care, 2.2 to 23.9%;4,5 and home care, 0 to 17%6,7) need to be interpreted with caution. Rather than reflecting true changes from pre-1990 rates (i.e., 5 to 11% in acute care with no reports from long term care and home care1), differences in incidence rates among studies and any apparent trends across time may be due to variations in basic definitions (e.g., stages of ulcers), formulas for calculating incidence rates, population characteristics (e.g., case mix), and sources of data (e.g., direct examination of patients, administrative data bases, medical record abstraction, and patient self-report). The effects of random variation should also be considered, particularly in studies with small sample sizes and low incidence rates.

Figure 1 - Click to enlarge in new windowFigure 1. RANGES OF PRESSURE ULCER INCIDENCE (STAGES I TO IV) 1990-2000
Figure 2 - Click to enlarge in new windowFigure 2. RANGES OF PRESSURE ULCER INCIDENCE (STAGES II TO IV) 1990-2000

Prevalence data are summarized on Table 2 and Figures 3 and 4. Variations in the range of prevalence rates, sample characteristics, and study methodologies were noted, therefore, results should be interpreted cautiously. Prevalence rates over the last decade ranged from 10 to 18% in general acute care,8 2.3 to 28% in long term care,6,9 and 0 to 29% in home care.6,10 Due to population and methodologic differences, valid comparisons cannot be made among these studies or to pre-1990 prevalence ranges (i.e., 3 to 14% in acute care, 15 to 25% in long term care, and 7 to 12% in home care1).

Figure 3 - Click to enlarge in new windowFigure 3. RANGES OF PRESSURE ULCER PREVALENCE (STAGES I TO IV) 1990-2000
Figure 4 - Click to enlarge in new windowFigure 4. RANGES OF PRESSURE ULCER PREVALENCE (STAGES II TO IV) 1990-2000

Three large multisite clinical studies in acute care reported prevalence rates of 14.8%, 15%, and 15% at the end of the decade; these studies provide the most accurate and current estimate of prevalence rates in acute care.11-13 Most pressure ulcers, regardless of setting, are partial thickness (Stage I-II) and are located on the sacrum or coccyx. The second most frequently occurring location for pressure ulcers is the heels.


Pressure ulcer prevention programs, based on evidence-based guidelines, have demonstrated successful outcomes. Several single-site studies have reported 50% or greater reduction in facility-acquired pressure ulcers following implementation of a pressure ulcer prevention program in acute care8,14-17 and long term care.18,19 Baseline pressure ulcer rates in these studies ranged from 4 to 24.2%;18,19 post implementation rates varied from 0.9 to 7%.16,19 Xakellis and colleagues20 reported a statistically significant decrease in post implementation incidence in a long term care facility. It is unclear whether these results have been achieved and sustained on a national basis.


Significant Achievements

The past decade has witnessed many significant achievements in pressure ulcer care, suggesting a reason for cautious optimism exists. The prevention and treatment of pressure ulcers has received increased attention from clinicians, researchers, and policy makers. Evidence-based clinical guidelines that describe best practices for pressure ulcer prevention and treatment have been published and disseminated widely. New technologies have been developed that reduce pressure over bony prominences and promote the healing of established ulcers. Care practices appear to have changed; for example, standardized risk assessments are now part of usual clinical practice in most settings. Furthermore, research studies and quality improvement initiatives performed in individual settings have shown that 50% reductions in pressure ulcer incidence rates are possible. The only large-scale study to examine trends in pressure ulcer rates has also documented a significant, but not as large, improvement. Using data from the Minimum Data Set (MDS) from a single nursing home chain, a 25% reduction in the rate of pressure ulcer development with the occurrence of fewer full-thickness wounds (Stage III or IV) was noted between 1991 and 1995.4 However, as described above, similar improvements have not been seen in other studies and additional evaluations are required. Most importantly, pressure ulcer care remains a topic of great interest for the coming decade. Ensuring patient safety is now a national priority, and reducing the prevalence of pressure ulcers is a national goal expressed within the Healthy People 2010 initiative for the nation's health.


Continuing Concerns

Despite these successes, significant concerns exist regarding whether improvements in pressure ulcer care can be sustained. The knowledge base regarding best practices for prevention and treatment of pressure ulcers remains incomplete. Well-designed, randomized clinical trials that may fill these gaps in knowledge are performed infrequently and funding for these studies is not readily available. Methods for translating research findings on pressure ulcers into clinical practice are also not well developed. Whereas guidelines have been published, how to successfully implement the best practices contained in these reports is uncertain. Such interventions will need to be developed if Americans are to see evidence of sustained, nation-wide reductions in pressure ulcer incidence.


The environment in which pressure ulcer care is provided is under stress. Many health care delivery organizations are facing severe financial pressures, necessitating reorganizations in the way in which care is delivered. Staff positions for those most experienced in pressure ulcer care are frequently being eliminated and necessary resources may be unavailable. Resources for pressure ulcer prevention may be in particular jeopardy, as the cost of treating any ulcers that do develop can be easily shifted to other providers. Any gains in pressure ulcer care achieved over the past decade can disappear rapidly in such an environment.


Finally, national databases that would allow the tracking of pressure ulcer rates over time are developed incompletely. Hospital discharge diagnoses frequently do not include an ICD-9-CM code for a pressure ulcer even when a Stage III or IV lesion is present. Furthermore, current codes cannot distinguish among pressure ulcers of different stages or those that are a complication of hospitalization from those present on admission. Whereas databases for long term care are becoming available, concerns over data reliability and validity remain. Pressure ulcer rates determined from these databases are considerably lower than those measured in clinical studies, suggesting that many pressure ulcers are being missed by databases. Valid information from national databases will be essential for monitoring trends in pressure ulcer rates and providing feedback to providers on their performance. Thus, improved databases serve as an essential basis for future clinical, educational, and public policy decisions.


Summary of Incidence and Prevalence

The knowledge is currently available to achieve large reductions in the rate of pressure ulcer development. Reductions in excess of 50% have been seen in individual clinical settings; yet a sustained nation-wide reduction in pressure ulcer incidence is not evident currently. It is imperative to continue to address best practices and accurately measure our nation's progress.


NPUAP Achievements

The mission of the NPUAP is to provide multidisciplinary leadership for improved patient outcomes in pressure ulcer prevention and management. Through this leadership, the NPUAP aims to improve clinical practice and reduce the incidence and prevalence of pressure ulcers. The NPUAP has three committees that work to fulfill this mission:


* Education Committee coordinates all educational programs, including conferences, bibliography updates, monographs, and information development.


* Public Policy Committee works to effectively strengthen legislative liaisons by creating a legislative agenda that can be addressed by the NPUAP (and associated organizations). The committee works with legislators and regulators to create a unified national approach to prevention and management of pressure ulcers.


* Research Committee is responsible for identifying the gaps in current knowledge, identifying research funding sources, and assisting in development and dissemination of research data.


Each of these committees has had a major role in improving pressure ulcer care in the past decade. These achievements are highlighted below.


Achievements in Pressure Ulcer Education in the 1990s

Over the past decade, the NPUAP has had a major role in educating clinicians, patients, and policy makers about best practices for prevention and treatment of pressure ulcers. This role has been accomplished through a variety of mechanisms. The NPUAP sponsors numerous conferences, including a biannual national conference and regional conferences on whether all pressure ulcers are avoidable. The NPUAP is responsible for distribution of educational materials, most recently a series of slide sets on pressure ulcer management that can be used in lectures by skin care experts. The NPUAP maintains a web site ( through which people can obtain information about pressure ulcers. The NPUAP has had a major role in refining definitions, such as on the staging and reverse staging of ulcers, so as to encourage the use of a common terminology. Additionally, the NPUAP has provided guidance on a number of difficult issues such as identification of early pressure-induced damage in darkly pigmented skin and methods of calculating incidence and prevalence rates for health care facilities and organizations. Through these efforts, the NPUAP has contributed to a substantially increased awareness about the problem of pressure ulcers, not only among clinicians, but also among patients, consumers, researchers, and policy makers.


Achievements in Public Policy in the 1990s

The NPUAP has been able to improve pressure ulcer care by influencing public policy over the past decade. The NPUAP has worked with other professional groups to ensure policy makers recognize pressure ulcers as a common, costly, and morbid condition. These efforts contributed to the decision by the Agency for Healthcare Research and Quality (AHRQ, formerly AHCPR) to develop clinical practice guidelines for pressure ulcers. Adoption of these guideline recommendations has led to improved practices. The NPUAP has helped establish a common terminology for use by policy makers in describing pressure ulcers, which was most evident in the effort to eliminate reverse staging. This led the Health Care Financing Administration (HCFA) to revise the Minimum Data Set for Post Acute Care (MDS-PAC), so as to incorporate the Pressure Ulcer Scale for Healing (PUSH) Tool for assessments of all post acute care patients. Instruments used in other settings, such as Outcome and Assessment Information Set (OASIS) in home care and MDS in nursing home care, have also been the subject of NPUAP consultations. The NPUAP provided expert testimony and consultation to HCFA on issues such as policies for dressing reimbursement, classification of support surfaces, and new technologies for pressure ulcer care. Finally, the NPUAP provided expert testimony during development of the Healthy People 2010 goals to ensure reduction of pressure ulcer prevalence is a national health care goal for the next decade.


Achievements in Research in the 1990s

The past decade has witnessed dramatic advances in the full spectrum of pressure ulcer research, ranging from basic science studies on the physiology of wound healing, rehabilitation studies on optimal support surfaces, qualitative descriptions of the pressure ulcer experience, to health services studies measuring the quality of pressure ulcer care. The extent of these research efforts is indicated by the ever-increasing number of pressure ulcer articles in the healthcare literature; more research on pressure ulcers has been published over the past decade than in the preceding 24 years. The quality of this research is demonstrated by the fact that pressure ulcer articles now appear regularly in leading medical journals. The NPUAP has done much to promote the performance and dissemination of research on pressure ulcers. Presentation of research abstracts is included in many NPUAP-sponsored conferences. The NPUAP sponsors novice investigators by providing pilot funding for small research projects. Quality in pressure ulcer research, education, policy, and practice is recognized by NPUAP through the biannual presentation of the Kosiak award.


Pressure Ulcer Prevention: Major Unresolved Issues

Despite the significant achievements in pressure ulcer care witnessed over the past decade, there remain many unresolved issues. Further improvements in pressure ulcer care will likely depend on how these issues are addressed. Among the major issues for the coming decade are the following:


* What are the best practices for prevention and treatment of pressure ulcers?


Relatively few clinical trials have identified best practices for prevention and treatment of pressure ulcers. Much of the current recommendations are based on expert opinion. Additional data are needed in such diverse areas as how best to identify high-risk patients, which preventive interventions should be targeted to which patients, and what are the optimal therapies for pressure ulcers.


* How can we determine and track the "true" incidence and prevalence of pressure ulcers on a national level?


If we are to improve pressure ulcer care, we must be able to measure it accurately, which will require data on the incidence and prevalence rates for pressure ulcers. As we have documented here, such data are difficult to obtain. Among the problems have been the lack of good data sources for describing pressure ulcers, the inconsistent use of major terms, and widespread uncertainty on how to do incidence and prevalence studies. Large databases will need to be developed and used that contain accurate information on pressure ulcers.


* How do we best translate research on pressure ulcers into evidence-based practice?


When best practices are identified, they must be translated into effective clinical practice. Whereas this is difficult in most clinical situations, it is especially problematic with pressure ulcer care. Pressure ulcer care tends to be multidisciplinary, with much of the actual work done by unlicensed staff. It is uncertain how best practices, such as those documented in clinical guidelines, should be implemented in this situation.


* Can national reimbursement policies be developed that are consistent with best practices?


Current policies may not reimburse providers for providing good care. If efforts to implement best practices are to be successful, they must be integrated with an appropriate reimbursement scheme.


* How do we resolve the question of whether all pressure ulcers are avoidable?


Considerable debate is ongoing currently as to whether all pressure ulcers are preventable or if some pressure ulcers will develop in high-risk patients even when quality care is provided. The resolution of this question has considerable regulatory, clinical, and legal implications. It is uncertain, though, what research will be required to address this question appropriately.


NPUAP Recommendations for the Future

NPUAP recognizes that public and professional awareness of the pressure ulcer problem has heightened to the point that it is now a matter of national concern expressed in the Healthy People 2010 goals. To help address these unresolved issues and support Healthy People 2010, the NPUAP reaffirms its mission to improve patient outcomes in pressure ulcer prevention and management through education, public policy, and research. The current NPUAP structure with committees on education, public policy, and research provides a multidisciplinary approach to address this national health issue.


Goals for Pressure Ulcer Education

The NPUAP plans to continue its leadership role in pressure ulcer education and expand its current activities. Specific education goals include:


* Develop diverse approaches for educating all health care providers.


- Provide regional and national conferences


- Implement web-based information for professionals


- Develop programs for nursing home caregivers



* Facilitate development and dissemination of additional evidence-based guidelines for pressure ulcers.


* Promote consistent education of professional and other care providers.


- Standardized core curricula


- Continuing education at local levels for direct-care providers


- Address issues related to pressure ulcer documentation



* Expand the target audience of education to include patients and families.


- Develop web-based information for lay people


- Rewrite patient education documents for easier reading



Goals for Public Policy

Through public policy initiatives, the NPUAP aims to have a major impact on improving pressure ulcer care in the coming decade. Specific goals for public policy include:


* Intensify efforts to achieve consistent and effective collaboration with governmental and regulatory policy makers on an international, federal, state, and local level. NPUAP will work with these entities through prospective strategic planning that will shape future policy.


* Enhance and expand our collaboration and liaison with professional organizations that share the NPUAP mission.


* Encourage regulations promoting fair reimbursements for interventions effective in prevention and treatment of pressure ulcers.


* Improve the quality of pressure ulcer data available from databases (MDS, ICD-9 codes) so as to help guide public policy decisions.


* Assist in implementation of measures of the quality of pressure ulcer care and dissemination of these results to consumers.


* Advocate for adequate resources for quality pressure ulcer care.


Goals for Research

The NPUAP has set goals to facilitate the research necessary to support improved pressure ulcer prevention and treatment. These include:


* Broaden financial support for the performance of quality pressure ulcer research over the next decade.


* Evaluate new pressure ulcer research as it is published and promote its incorporation into clinical guidelines.


* Identify effective strategies for translating pressure ulcer research into practice.


* Develop national and international support surface performance standards.


* Establish an agenda for pressure ulcer research that focuses on major areas of uncertainty.


* Promote development of reliable and valid data sources for use in pressure ulcer research.



Recommendations for Prevalence & Incidence Definitions and Formulas

Lack of clarity and consistency in definitions and calculation formulas impedes our understanding of pressure ulcer prevalence and incidence. Standardization of definitions and formulas will enhance comparability of data among future studies. NPUAP recommends the following definitions and formulas for determining pressure ulcer prevalence and incidence.


Prevalence is defined as a cross-sectional count of the number of cases at a specific point in time, or the number of persons with pressure ulcers who exist in a patient population at a given point in time.21-24 In assessing prevalence, it does not matter in what setting the pressure ulcer was acquired. Prevalence rates are often expressed by the following formulas: EQUATIONS 1 and 2

Equation 1 - Click to enlarge in new windowEquation 1
Equation 2 - Click to enlarge in new windowEquation 2

Incidence, the number of new cases appearing in a population,24 indicates the rate at which new disease occurs in a population previously without disease.25 Incidence is the number of persons initially ulcer-free, who develop a pressure ulcer within a particular time period in a particular population.23 Several approaches to measuring incidence have been used. Cumulative incidence is defined as the rate of new pressure ulcers in a group of patients of fixed size, all of whom are observed over a period of time. The formula for calculating incidence using this approach is as follows: EQUATION 3

Equation 3 - Click to enlarge in new windowEquation 3

A limitation of this approach is that it does not account for pressure ulcers that may occur in persons admitted to the setting after the study population is defined. Thus, it may not reflect the true incidence of new ulcers in the setting.


A second approach measures the number of new cases of pressure ulcers that occur in an ever-changing population, where people are under study and susceptible for varying lengths of time (e.g., patients in a nursing home). Incidence is calculated as the number of persons developing pressure ulcers per 1000 patient days and is referred to as incidence density. The formula for calculating incidence using this approach is as follows: EQUATION 4

Equation 4 - Click to enlarge in new windowEquation 4

Common pitfalls in calculating pressure ulcer prevalence and incidence may be avoided by:


* Defining the population and applying it consistently throughout the study.


* Counting the number of persons with pressure ulcers; not the number of pressure ulcers.


* Counting only pressure ulcers, not other wounds.


* Defining stages of pressure ulcers to include and assessing accurately.




The NPUAP will continue to be at the forefront of providing leadership in promoting the delivery of optimal pressure ulcer care and improving patient outcomes. Whereas the NPUAP has accomplished much over the past decade in improving care, as illustrated in this report, we are still uncertain as to the magnitude of the impact of this work in reducing the incidence and prevalence of pressure ulcers. Interpretation of prevalence and incidence rates should be done cautiously and in the context of the methodologic issues raised throughout this monograph.


Through the recommendations outlined in this summary, we expect not only to improve pressure ulcer care, but also to enhance our ability to document these improvements through substantial reductions in the incidence and prevalence of pressure ulcers by the end of this decade. To help address these unresolved issues and support the Healthy People 2010 objectives, the NPUAP reaffirms its mission to improve patient outcomes in pressure ulcer prevention and management through education, public policy, and research.




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