Pressure Ulcer Risk Factors Among the Elderly Living in Long-term Institutions

Abstract: Although many intrinsic and extrinsic risk factors are involved, pressure is the most important factor in the development of pressure ulcers. The elderly are more susceptible to the development of these skin lesions as a result of changes associated with the aging process. The aim of this study was to identify the risk factors for pressure ulcers in the elderly living in long-term institutions. Methods. An analytic cross-sectional study of 40 patients age 60 years and older with pressure ulcers was conducted in six long-term institutions for the elderly (LTIE) in the West Side of São Paulo, Brazil. The present study evaluates pressure ulcers and their associated risk factors. Statistical analysis was performed using Pearson’s chi-square test, Student’s t-test, and Fisher’s exact test. Results. A statistically significant association between the risk factors evaluated in this study and the development of pressure ulcers in the sample was not found. According to the Braden scale, 67.5% of the patients were at high risk for pressure ulcer development. Fifty-one pressure ulcers were detected, with the majority (56.2%) being located in the sacral region. In the present study, more than 50% of the patients had low sensory perception, mobility, nutrition, and friction and shear subscales scores. The most prevalent risk factors were advanced age (mean, 83.8 years), length of stay that exceeded 31 months, white skin, neuromotor and skeletal muscle disorders, urinary and fecal incontinence, and continuous use of sedatives, analgesics, and hypotensives. Conclusion. The knowledge of risk factors is essential for healthcare professionals in planning effective prevention programs that target the elderly living in LTIE.
Address correspondence to: Julieta Chacon, RN, MS Universidade Federal de São Paulo–UNIFESP Rua Napoleao de Barros 715 04023-062 São Paulo, Brazil Phone: +55 11 5576 4118 Email: julieta.chacon@uol.com.br

     Pressure ulcers are defined as areas of cellular necrosis in the skin and surrounding tissues that tend to develop when soft tissue is compressed between a bony prominence and a hard surface for a prolonged period of time.^1,2 Constant pressure reduces blood flow in these areas and damages the skin.³ Pressure ulcers are found mainly in the occipital, sacral, ischial, and trochanteric regions; other common body locations for pressure ulcers include the ear, elbow, side of the leg, knee, malleolus, calcaneous, and end of the toes.^1,2,4–6      Epidemiologic studies have reported pressure ulcer prevalence rates ranging from 7% to 12% in long-term institutions.⁷ Higher prevalence rates of chronic lesions are observed among patients age 60 years and older—71% of ulcers occur in patients older than 70 years.⁴ Pressure ulcers are the most common complication among elderly hospitalized patients and account for 70% of the complications observed.⁴ A study, which was part of the Brazilian Healthcare Program for the Elderly, reported pressure ulcer prevalence of 11.3%.⁸      Pressure ulcers have a significant socioeconomic impact, which results in high treatment costs and prolonged lengths of stay. In the United States, treatment costs for pressure ulcers range from $2000 to $30,000 per patient with an average daily cost of $80.42. The estimated national annual cost range from $5 to $9 billion; the aggregate cost of care for patients with chronic wounds exceeds $20 billion annually.^7,9 Treatment cost estimates for pressure ulcers in Brazil are not available.¹⁰ Pressure ulcer care costs for the institutionalized elderly are directly related to ulcer stage and time of diagnosis. In the United States, the cost of treatment for a Stage II pressure ulcer is close to $450, which increases to $1000 when hospitalization is needed.¹¹      Risk factors for pressure ulcers may be classified as intrinsic and extrinsic. The intrinsic risk factors include immobilization, cognitive deficit, chronic diseases (eg, diabetes mellitus, cerebral or spinal cord injury, and vascular and neuromuscular diseases), decrease in pain sensibility (peripheral neuropathy), use of prosthesis, use of certain drugs (eg, sedatives), urinary and fecal incontinence, poor nutrition, and advanced age.^3–5,12 The four most important extrinsic risk factors are pressure, moisture, friction, and shear.^1,4 Pressure is a crucial factor in the development of pressure ulcers. For instance, a pressure of 70 mmHg applied on a bony prominence for 2 hours or more is sufficient to cause ischemic lesions.^2,4 Pressure, time, and ischemia reperfusion injury form a complex physiological relationship that may differ significantly from patient to patient.¹³ Tissue damage may occur rapidly and has been noted after less than 1 hour of unrelieved pressure.¹⁴ Using alternating pressure surfaces to relieve pressure at 5-minute intervals helps to prevent ischemia reperfusion injury and consistently has been shown to minimize tissue damage.¹³ Further research is needed to establish the link between ischemia reperfusion injury and pressure ulcer development in humans in order to create an evidence base for patient repositioning; repositioning every 2 hours is a practice that has yet to be evaluated.¹⁵      The older population is more susceptible to the development of skin wounds due to changes associated with the aging process that increase the fragility of the skin.¹⁶ Among these changes, one may cite the thinning of cell layers, decreased vascularization, cell proliferation, and delays in the healing process. Skin sensibility, pain response, barrier function, and inflammatory response are also reduced with aging, which makes skin more vulnerable to injury.¹⁶      Knowledge of pressure ulcer risk factors is essential for healthcare professionals in planning effective prevention programs that target the elderly living in long-term institutions. Therefore, the aim of this study was to identify these risk factors among the elderly residing in LTIE in the West Side of São Paulo, Brazil.

Methods

     An analytic cross-sectional study was performed. The sample consisted of 40 patients with pressure ulcers, who were residing in six LTIE located in the West Side of São Paulo, Brazil. The participating institutions were randomly selected. All participants were age 60 years and older¹⁶ who agreed to participate in the study. Each institution was evaluated separately. Data collection was performed between May 2007 and August 2007.      The Research Ethics Committee of the Federal University of São Paulo (UNIFESP) approved the study. Written informed consent was obtained from all patients or from their representatives. The names of the LTIE were omitted to maintain confidentiality.      Patients with pressure ulcers were evaluated and had their demographic and clinical data collected from patient records and through interviews. The first author (Chacon) conducted all assessments. The skin was carefully inspected and all pressure ulcers were identified. Upon detection, a thorough examination of the pressure ulcer was performed. Ulcers were classified according to the National Pressure Ulcer Advisory Panel (NPUAP). Pressure ulcer risk was assessed using the Braden Scale.      Statistical analysis was performed using Pearson’s chi-square test, Student’s t-test, and Fisher’s exact test. All statistical tests were carried out at a significance level of 5%.

Results

     The sample consisted of 40 elderly patients with pressure ulcers from six LTIE located in the city of São Paulo.      The distribution of socio-demographic characteristics of the institutionalized elderly patients with pressure ulcers (Table 1), as well as the distribution of their clinical characteristics (Table 2), length of stay at two time points (Table 3), distribution of pressure ulcers by stage in different anatomical locations (Table 4), and distribution of total scores (Table 5) and Braden subscale scores (Table 6) were reported.      The patients included in this study were between 65- and 100-years-old; 29 (72.5%) patients were 80 years or older. Thirty-five (87.5%) of the patients with pressure ulcers were women, 5 (12.5%) were men, 38 (95%) had white skin, and 2 (5%) had non-white skin. Regarding marital status, 32 (80%) were widow(er)s, 6 (15%) were single, and 2 (5%) were married. The most commonly associated conditions were hypertension (47.5%), cardiovascular/respiratory diseases (37.5%), senile dementia (37.5%), and neurological disorders (27.5%). The medications most used by the patients were vitamins, antacids, cerebral vasodilators, ferrous sulfate and platelet antiaggregants (90%), followed by antihypertensive medications (45%), anxiolytics and antidepressants (27.5%), hypoglycemics (12.5%), and analgesics (2.6%). The mean number of medications per patient was 4.84. Eleven patients (7.5%) were smokers and one (2.5%) was alcohol dependent.      Fifty-one pressure ulcers were recorded in the sample. Pressure ulcers were found mainly in the sacral (72.5%), trochanteric (17.5%), and ischial (5%) regions. Sixteen (40%) of the patients had urinary incontinence and 11 (27.5%) had fecal incontinence. Twenty-seven (67.5%) patients were at high-risk for pressure ulcer development; however, a statistically significant difference was not found either between the total scores (P = 0.644) or Braden subscale scores.

Discussion

     In Brazil, 20 million people are age 60 years or older and account for 10.5% of the Brazilian population. Over the next 20 years, the elderly Brazilian population is estimated to reach more than 30 million and will represent almost 13% of the total population.^17,18      The accelerated aging rate of the Brazilian population creates new challenges for the Brazilian contemporary society, especially considering that this process is taking place amidst a scenario of deep social, urban, industrial, and familial transformations. Long-term care institutions are becoming increasingly necessary with the rise in the elderly population.^19–21      Institutionalized elderly patients are a fragile group within the population and are characterized by complex clinical conditions, multiple diseases, impairments, malnutrition, and cognitive decline.¹      Pressure ulcers are a common problem in many healthcare settings and are frequently found in acutely ill hospitalized patients or in patients with chronic diseases residing in long-term care institutions.¹      Diseases related to neuromotor and skeletal muscle disorders impair quality of life, self-care, and functional capacity among the elderly, consequently interfering with nutrition and levels of sensory perception, mobility, activity, and moisture, which are classic risk factors for pressure ulcer development.²² In the study population, the most commonly associated conditions were hypertension (47.5%), cardiovascular/respiratory diseases (37.5%), senile dementia (37.5%) [predominantly Alzheimer's disease (15%)], neurological disorders (27.5%), diabetes mellitus (12.5%), psychiatric disorders (7.5%), and neoplasia (2.5%). It is important to point out that some of the patients had more than one condition.      Pressure ulcers are characterized as an insidious lesion with severe consequences that lead to increased mortality and morbidity rates (eg, infections, pain, depression, and surgery) and prolonged lengths of stay.^1,23–26      In the present study pressure ulcers were found mainly in the sacral, trochanteric, ischial, and calcaneal regions. Patients who remain in a supine position are subject to a higher pressure on the sacral region. Patients who remain in a lateral position or seated with limited mobility may develop pressure ulcers in the trochanteric and ischial regions.^12,27–30      Stage II pressure ulcers accounted for 51% of the wounds found upon examination. Previous studies reported that 70%–80% of all ulcers detected were Stage I or Stage II.^1,29–31 However, in many cases, Stage I pressure ulcers (pre-ulcers) are not detected by the healthcare professional because no lesion is seen, making it hard to distinguish between a reactive and a non-reactive erythema, which may evolve to advanced stages if the causative stimulus is not removed.^{12,27–29,32,33}      In the present study, most of the patients with pressure ulcers (87.5%) were female, which aligns with the findings of previous studies.^{1,25,27,28,32} According to the Brazilian Institute of Geography and Statistics (IBGE), the majority of the elderly population in Brazil are female; life expectancy is greater in women than in men.¹⁷ However, female gender has yet to be identified as a pressure ulcer risk factor.⁵      Pressure ulcers were present predominantly in patients with white skin (95%), which concurs with previous studies.^{1,6,12,23,30,32,34,35} The literature shows that black skin is more resistant to external aggressions, such as moisture and friction, due to its more compact stratum corneum. However, it is difficult to detect pre-ulcers in individuals with black skin.^12,36      The patients included in this study were between age 65 and 100 years (mean, 84 years). The association between advanced age and pressure ulcer occurrence was not statistically significant, which is consistent with previous studies,^1,27,28 although others have reported contrary results.^23,35      Length of stay for the elderly in the LTIEs ranged from 1 to 132 months (mean, 32 months). A significant correlation between pressure ulcer incidence and length of stay in the LTIE was not found. It is known that a prolonged length of stay in hospitals, as well as in LTIEs, may increase the risk for pressure ulcer development.^27,28,37 The distribution of the number of patients with pressure ulcers according to the length of stay is shown in Table 3. Stage I pressure ulcers were indentified in patients with a short length of stay (1 month), as well as in patients with a longer length of stay (6–8 months). Stage II ulcers were detected in the elderly 2 months following admission. Stage III and IV ulcers were detected 12 months following admission.      Among the medications most used by the patients were vitamins, antacids, cerebral vasodilators, ferrous sulfate and platelet antiaggregants (90%), followed by antihypertensive medications (45%), anxiolytics and antidepressants (27.5%), hypoglycemics (12.5%), and analgesics (2.6%). The mean number of medications per patient was 4.84. The continuous use of medication, although necessary, may contribute to the development of pressure ulcers. Sedatives and analgesics reduce pain, but affect mobility. Antihypertensive agents may affect blood flow and reduce tissue perfusion, which makes tissue more susceptible to pressure.^6,12,30      Braden Scale scores ranged from 7–18 (mean, 10.5). According to the Braden Scale, 67.5% of the patients were at a high risk for pressure ulcer development.²² This result is important because it shows the necessity for preventive measures combined with a systematic evaluation of elderly patients at risk for pressure ulcers performed on a daily basis.^{25,28,34,38–40} These evaluations would most appropriately be carried out by using validated scales based on the physiopathology of ulcers, such as the Braden scale, which allows important aspects of the formation of pressure ulcers to be analyzed by the six subscales: sensory perception, moisture, activity, mobility, nutrition, friction, and shear.⁴¹      Another important factor in the development of pressure ulcers is excessive exposure of the skin to moisture due to urinary and fecal incontinence and perspiration. Moisture macerates and weakens the skin, which becomes more susceptible to injuries, especially those caused by friction and shear.^{1,5,12,22,27,37,42–45} Urinary and fecal incontinence contribute to the development of pressure ulcers by constantly exposing the skin to excessive moisture and fecal matter, which are caustic to the skin. Moreover, urinary and fecal incontinence are medical conditions that require a therapeutic approach, since the loss of sphincter control is an embarrassing condition that can have a significant social and psychological impact, cause changes in daily activities, affect interpersonal relationships, and frequently is the main reason an older person is admitted to a LTIE.^1,46      The worst scores were obtained in the moisture subscale. In the present study, 40% of the patients had urinary incontinence and 27.5% had fecal incontinence, identifying the sample as high risk for pressure ulcer development. More than 50% of these patients had low scores in all Braden subscales with scores of 1 and 2 corresponding to the worst state of health (Table 6). Decreased sensorial perception associated with low mobility result in lack of response to pressure loading in elderly persons, who become more susceptible to friction, shear, and pressure ulcer development; these patients are considered at high risk for pressure ulcers according to the Braden Scale.^1,47 A pressure ulcer is a major impairment to quality of life and often results in worsening of other conditions and suffering, thus increasing length of stay, the need for nursing care, as well as treatment costs.^26,48 Most of these wounds could be avoided if healthcare professionals were: 1) more knowledgeable concerning the function and characteristics of elderly skin and its various peculiarities, 2) able to identify risk factors for pressure ulcer development with a specific validated scale, 3) able to implement efficient prevention strategies associated with higher quality care. Early diagnosis and treatment that follows appropriate institutional protocols for pressure ulcer prevention lead to an extended life expectancy and better quality of life for the institutionalized elderly.^1,12,25,28      Study limitations. The main risk factors for pressure ulcer development in institutionalized patients were identified in the present study, although there was no statistically significant association between the risk factors evaluated in the study and the development of pressure ulcers in the sample. This may be attributed to the small size of the sample. A need exists for additional well-designed studies (using larger samples) to be conducted in different parts of São Paulo to identify predictive risk factors for pressure ulcers in order to develop prevention strategies tailored for each population.

Conclusion

     The most prevalent risk factors indentified among the elderly living in six LTIE in the West Side of the city of São Paulo were advanced aged, length of stay, white skin, neuromotor and skeletal muscle disorders, urinary and fecal incontinence, and continuous use of sedatives, analgesics, and hypotensives. Our results provide background information that may be useful in designing best practice protocols for prevention and treatment of pressure ulcers, thereby reducing prevalence and morbidity among the institutionalized elderly. Knowledge of pressure ulcer risk factors in the study region is essential for healthcare professionals in planning effective prevention programs that target the elderly living in LTIE in addition to conducting comparative studies of risk factors and incidence of pressure ulcers in other regions of São Paulo.