Dry skin, or xerosis, is a problem for 59% to 85% of our elderly population (Beauregard & Gilchrest, 1987; Eliopoulos, 1988; Frantz & Kinney, 1987; Tindall & Smith, 1963). Of aging skin problems, pruritus is most common and xerosis is responsible for up to 85% of pruritus (Herman & Gilchrest, 1989). However, those with xerosis may not recognize it and not seek treatment; those who do treat their skin problems may do so without consulting a health care provider even though their treatments are often not helpful (Beauregard & Gilchrest, 1987).
Long thought to be an age-related decrease in sebum production that allowed increased water loss from the skin and decreased hydration of the stratum corneum, research has shown no such significant relationships (Frantz & Kinney, 1986). Skin is dry not because it lacks grease or skin oils, but because it lacks water. Water, absorbed by the skin through bathing, will hydrate the skin but will rapidly be lost to the atmosphere and has minimal long-term effects. Therefore, current therapy for dry skin emphasizes the use of occlusive topical agents to prevent moisture loss from the skin (Parent, 1985)- the "greasier, the better," suggests Gilchrest (1986).
The literature indicates, however, that some elements of battling and environment may contribute to dry skin: soap, excessive perspiration; dehydration, smoking, stress; lack of humidity, and exposure to the sun. Additionally, factors thought to be related to dry skin such as hypothyroidism, diabetes, malignancies, hepatic or renal diseases, psychoneuroses, or medications, must be ruled out in cases of severe pruritus or xerosis (Arndt, 1983; Cornell, 1986; Dotz & Berman, 1984; Fitzsimmons, 1983; Gioella & Bevil, 1985; Hogstel, 1983; Parent, 1985; Forth & Kapke, 1983; Shelley & Shelley, 1982; Walther & Harber, 1984).
PURPOSE OF STUDY
The overwhelming conclusion of the literature, then, is that dry skin can be treated through the addition of moisture through bathing and prevention of moisture loss with use of a mild, superfatted soap for cleansing; a humid environment; and by application of an emollient to prevent rapid evaporation of water (Anderson, 1971; Arndt, 1983; Atkins, 1977; Fitzsimmons, 1983; Hogstel, 1983). There is little agreement, however, on brand of soap; frequency or mode of bathing (shower vs. tub); occlusive agent; or desired humidity. Even for factors on which there is agreement - tepid water; soft clothing and patting dry; and laundry processes not using starch or anti-static agents in drying (Arndt, 1983; Parent, 1985; Shelley & Shelley, 1982) - there is little research support.
The purposes of this study were to: 1) test an intervention designed to treat dry skin, 2) test the independent and interactive effect of frequency and mode of bathing, and 3) analyze the effect of age, gender, disease history, fluid intake, and humidity on the effectiveness of the intervention.
Subjects were enrolled in the study for a total of 18 weeks: 6 weeks for the collection of baseline data during which subjects followed their usual bathing practices; 6 weeks of intervention; and 6 weeks post-intervention in which subjects returned to their previous usual bathing practices. Six weeks was determined as sufficient for testing the effectiveness of the intervention because the normal cell moves from the basilar level to the epidermis in about 26 days and this time may double in the elderly. Data were collected every 2 weeks during the 18-week period because skin changes due to treatment or toxins can take up to 2 weeks to be manifested in the elderIy (Fenske, 1982). All subjects followed the tested protocol but continued their usual frequency and mode of bathing. The bathing protocol that was followed by all subjects included the following:
1. Dove soap for cleansing;
2. Water temperature of 90°-105°;
3. Immersion in a tub and pouring water over body parts or shower for 10 minutes;
4. Patting the skin dry with a cotton towel rather than rubbing;
5. Mineral oil over all body parts;
6. Linen that has been thoroughly rinsed of detergent and without antistatic; and
7. Cotton clothing.
Subjects from the community were identified through community health care settings, newspaper, community cable, and radio advertising. For the identification of institutionalized subjects, nurses were asked to identify residents with dry skin in their caseloads. Approximately half of the subjects (47%) lived in their own homes, 19% in independent supported-living apartments, and the remaining 34% lived in long-term care institutions. Subjects were paid $35.00 to participate and were required to be 55 years of age or older; each was seen by a dermatologist so that any subject with pathological dermatoses was eliminated. Of the 169 subjects who were screened, 160 gave consent to participate. Following explanation of the study requirements, 143 enrolled in the study. Due to death, hospitalization, and withdrawal, data from 122 subjects were collected at all nine data collection points.
Dry skin is considered to occur primarily on the extremities, although the trunk and face may be affected (Arndt, 1983; Parent, 1985). Symptoms include roughness, flaking, scaling, chapping, pruritus, and in severe cases, inflammation, fissuring, and erythema (Arndt, 1983; Dotz & Berman, 1984; Gilchrest, 1986; Parent, 1985). Although extensive work exists on history and assessment of the integument (Delancy & North, 1983; Hannigan, 1978; Hogstel, 1983; Malkiewicz, 1981; Pearson & Kotthof, 1979; Urosevich, 1981), the research base for measurement of dry skin is limited to two extant instruments: the Black and Gaspar Foot Assessment Tool (BGFAT) and the Skin Condition Data Form (SCDF). The BGFAT was used to evaluate the effectiveness of an intervention for treating elderly persons with dry feet and has no reported psychometric properties (Brown, Boosinger, Black, Gaspar, & Sather, 1982). The SCDF was used with 76 subjects over the age of 65 to analyze the relationship between sebum content and dry skin (Frantz & Kinney, 1986). Hardy (199Oa) reported the content validity and interrater reliability of a modified SCDF as part of a pilot study, describing content validity by experts and interrater reliabilities of 87%, 63%, and 68%, respectively, on history, current skin practices, and observed dryness.
For purposes of this study, the SCDF with a modified scoring scheme was used. For observed skin dryness, the rater assigned a value of 1 (absent), 2 (mild), or 3 (severe) on the observed redness, flaking, scaling, and cracking. Operational definitions were:
1. redness: inflammation varying from pink to bright red;
2. flaking: dandruff-like flakes appear when fingers are lightly rubbed over skin surface;
3. scaling: fish-like scales on skin's surface;
4. cracking: parched appearance of skin that resembles dry earth.
Two trained raters independently administered the modified SCDF on 18 subjects in an analysis of interrater reliability. A 94% interrater reliability was found using a formula suggested by Polit and Hungler (1987) in which the number of agreements is divided by number of agreements plus the number of disagreements.
A large water thermometer was given to each subject, or to the participating institution, with directions to set bath or shower water temperature at between 90° and 1050F. A calibrated hygrometer was used by the data collectors for measuring environmental humidity.
Data were collected by the investigator and trained research assistants. An informational memo was given to subjects as a reminder to change their bathing practices only during the middle six weeks. A form outlining the protocol was used to monitor completion of the protocol. In cases in which baths were given in institutions, placards with enlarged print showing the protocol were placed in bathrooms. To monitor compliance with the protocol, adequate Dove soap bars and mineral oil according to the specified bathing frequency of the subject were provided every two weeks so that at the end of every two-week period no supplies would remain and new supplies would be necessary.
Mode and frequency were treated as categorical variables: bathing vs. showering and low (1-2), moderate (3-4) or high (5 or more) frequency of baths or showers per week. The statistical design was a 2 (mode) by 3 (frequency) factorial design with 9 repeated measures on one factor, skin dryness. Other variables were dichotomized for analysis: low (<40%) or high (40% or greater) humidity; low («?2000 cc) or high (>2000 cc) daily fluid intake; use or nonuse of drugs thought to be related to dry skin (steroids, thyroid supplement, and diuretics); and presence or absence of history of chronic disease. Age was categorized in three groups: 65 years or less, 66 through 74, and 75 or greater.
Age ranged in this sample from 55 to 102 years (mean=75 years). There were 25 subjects ranging in age from 55 to 65 years, 50 from 66 to 74 years, and 66 subjects were 75 years or older. Fifty-seven males (40%) and 86 females (60%) comprised the final sample. More subjects showered («=81) than bathed (n=59) and subjects bathed less frequently (mean=1.4) than showerers (mean=2.1). It is interesting to note, however, that the largest number of subjects reported low frequency (1-2 per week) bathing, whether they showered (n=30) or tub-bathed (n=35). The majority of subjects (58%) lived in humidities less than 40% and the majority of subjects (58%) ingested greater than 2000 cc of fluid per day.
Table 1 presents a summary of the repeated measures ANOVA findings of the study, showing statistical probabilities for the individual dependent variables and the total skin score (summed score). In the categorical variables of interest, age was not significant except in scaling (F=1.84, df=16, p=.023), the younger subjects having higher scaling scores indicating a less therapeutic effect than for older subjects and total score (F=2.32, df=16, p=.002), the middle age group being dryer at baseline and dropping more significantly during intervention than the other two age groups. Women were dryer than men overall (F=2.46, df=8, p=.012) as well as in scaling (F=2.90, df=8, p=.003) and redness (F=5.26, df=8, p=.000) which indicates women responded less favorably than men to the treatment.
A mean of the nine humidity scores was calculated and used to divide subjects into high and low humidity groups. A 2 (low and high) X 9 repeated measures ANOVA revealed significant differences in all dependent variable scores: redness (F=2.01, df=8, p=.043), flaking (F=2.52, df=8, p=.010), scaling (F=6.28, df=8, p=.000), cracking (F=2.55, df=8, p=.009) and total (F=4.83, df=8, p=.000) scores, indicating subjects in high humidity environments responded more favorably to the treatment. Subjects with a fluid intake of 2000 cc or more a day presented significantly lower signs of dryness in flaking (F=2.66, df=8, p=.007), scaling (F=2.73, df=8, p=.006) and in total score (F=2.89, df=8, p=.003) than subjects with a fluid intake of less than 2000 cc per day.
In the category of chronic history relevant to dry skin, such as smoking, Parkinson's disease, asthma, etc., 33% (n=48) had none, 29% («=41) had 1 factor, 16% («=22) had 2 factors, 8% (n=12) had 3 and 14% («=20) had 4 to 8 factors in their history. Disease history was significant for redness (F=2.62, df=8, p=.008), those with a history having significantly lower redness scores over time. This finding may indicate that persons with a history or presence of a disease etiologically related to dry skin may respond more favorably to this intervention, particularly in reduction of redness, than individuals who have no related chronic disease but perhaps have a maturation etiology.
A repeated measures ANOVA was performed on the nine flaking scores for the two drug groups (use and nonuse) showing a significant effect (F=3.40, df=8, p=.001). Subjects who reported taking the drugs of interest (n=23) had higher flaking scores throughout the study than non-users («=98). However, the width of the gap in scores was greater prior to and following the intervention than during the intervention. That is, the average flaking score prior to the intervention was 2.35 higher in the drug users, 0.40 higher during the intervention, and 3.1 higher following the intervention. This indicates that in the absence of the intervention, the drugs were more disturbing to skin integrity.
Summary of Statistical Probabilities fp) of Variables In Study
The main effects of mode and frequency are also shown in Table 1. The only significant decrease for the independent effect of mode was observed in flaking (F=2.54, df=8, p=.010), the showerers having more reduced scores during intervention. As to the independent effect of the frequency of intervention, except for cracking, all dependent variables were significantly reduced over time (redness: F=2.99, df=16, p=.000; flaking: F=3.62, df=7.79, p=.000; scaling: F=2.71, df=16, p=.000; and total: F=4.33, df=16, p=.000). This finding is consistent with pilot findings (Hardy, 199Oa). The only statistically significant interaction was observed in the effect of frequency by mode on scaling (F=1.90, df=16, p=.018).
The Figure graphically illustrates the overall trend in dry skin scores across the nine time points for the low (1-2), medium (3-4), and high (5 or greater) frequency showerers and tub bauiers. As the Figure shows, all frequency /mode groups followed the same trend in dryness scores, dropping more at time 5 and showing some latent effects into time 7, botti findings of which are consistent with the fact that older subjects may manifest skin changes slowly. The interactive effect of mode and frequency was very limited, the high frequency showerers being the only ones to demonstrate significantly reduced scores on scaling (F=1.90, df=16, p=.018).
Clearly, the intervention tested in this study is within the scope of nursing practice. The findings provide an empirical basis for clinical decisions in the bathing practices utilized by nurses in multiple practice settings and the recommendations made to patients for self-care. Table 2 illustrates the specific choices of soap, bathing frequency, battling mode, emollient, water temperature, and environmental humidity, that optimally address dry skin.
The degreasing and oil-dissolving properties of soap may make skin dry after the early and middle stages of life (Shelley & Shelley, 1982). A "mild," non-irritating soap has a decreased detergent content but also has a decreased cleansing ability. Superfatted soaps, on the other hand, attack the problem of reducing dehydration by providing an excess of emollient material, which results in a thick film of oil being deposited on the skin surface (Dotz & Berman, 1984). The consensus is that non perfumed superfatted soaps that do not contain hexachlorophene are most effective in treating dry skin in the elderly. Some specific brands are Basis, Dove, Tone, Caress (Arndt, 1983; Walther & Harber, 1984), Neutrogena, and Emulave (Forth & Kapke, 1983). Dove, used in this study, is the only superfatted soap that has been reported as being tested in a laboratory study and was found to be less "irritating" man other soaps (Frosch & KHgman, 1974).
There is little consensus in the literature about the frequency of bathing. Most suggest limiting bathing to one to three times weekly (Arndt, 1983; Hogstel, 1983; Shelley & Shelley, 1982). Epstein (1983) suggests, however, that unless battling more than once a day, there is no reason for those with dry skin to cut down on bathing. This suggestion is consistent with the theory that one element of effective treatment for dry skin is superhydration. Age, however, may be an important factor to consider in prescribing bathing frequency; Beauregard and Gilchrest (1987) reported that subjects aged 80 or older had a tendency to bathe somewhat less frequently (5.4 vs. 6.1 times weekly). Thus, older subjects may not respond favorably to prescription for more frequent bathing. The fact that higher frequency bathing or showering may have a significant role in decreasing skin dryness has implications for recommendations made by nurses to clients presenting with dry skin. A troubling fact is that a minimum of two baths weekly is a regulatory requirement in many nursing homes, perhaps inadequate for effective treatment of dry skin.
Unfortunately, there is no research addressing the rationale used by nurses in making bathing mode treatment choices; safety, time, and the medical regimen are often major considerations whether the nurse is in an assistive role or whether the nurse is counseling a client on bathing choices. For instance, nurses working with demented elderly make this treatment choice based on prevention of catastrophic reactions often brought on not only by the bath but during the transportation to the tub or shower room. In other cases, tub bathing is not done due to limited mobility and lack of physical support to enter and exit the tub (Hardy, 199Ob). Age may also be a factor in the choice of bathing mode according to a study of 68 non-institutionalized subjects aged 50 to 91 in which subjects aged younger than 78 used both the tub and the shower frequently while subjects aged 80 years and older often related exclusive use of either tub (38%) or shower (21%). Whether this was due to available bathroom facilities, physical limitations or simple preference was not ascertained (Beauregard & Gilchrest, 1987).
Figure. Plot of skin dryness scores over time by frequency /mode groups.
Optimal Combination at Factors That Effectively Tteat Dry Skin
There are some indications in the literature for choice of bathing mode. Walther and Harber (1984) suggest a bedbath or partial bath but this is not only intuitively contradictive to the theory that water absorption must be maximized in dry skin treatment but has been shown by Lindell and Olsson (1990) to be associated with significantly greater number of vulvovaginal signs and symptoms in women who had a bedbath versus those who were showered. This has important implications for patients who primarily during acute phases of illness are bedbathed. Although Pearson and Kotthof (1979) suggest a soaking or submerging for 10 to 15 minutes and Spoor (1958) and Brown, Boosinger, Black, Gaspar, and Sather (1982) reported successful treatment with soaking baths, total immersion may not always be practical. Epstein (1983), however, suggested that showering was as effective as bathing. Because nursing home and hospitalized patients are most frequently showered, the finding that bathing or showering were not significantly different in the effectiveness of the protocol tested in this study has important clinical implications.
An oil base is consistently suggested as the primary ingrethent in an emollient of choice following a bath, while skin is still wet and water will be trapped (Arndt, 1983; Cornell, 1986; Dotz & Berman, 1984; Shelley & Shelley, 1982). Occlusive agents lubricate the skin surface and make the skin feel smoother and less dry. This improves the greasy feeling and once the water has been trapped, the oily film remaining on the skin is generally sufficient to retard transepidermal water loss. Keratin softening agents, such as urea, lactic acid, and allantoin, may be added to dry skin products to soften the skin and improve its appearance but they do not affect the water content of the skin and should be used in conjunction with occluding agents.
The research base for choice of emollients is limited. Brown and colleagues (1982) used mineral oil because of low cost and ability to hold water in testing an intervention for dry feet. Boisits (1986) reported that in a clinical trial of occlusive agents at a relative humidity of 20%, there was a 98% reduction in moisture loss with petrolatum, an 83% reduction with lanolin, and a 31% reduction with mineral oil. Weiner et al. (1973) used Dermo-Pedic Foot Lotion, a lotion containing "ethoxylated" lanolin in an aqueous base with allantoin and Spoor (1958) tested the effects of a water-dispersable bath oil, Sardo. Other commercial brands which are noted in the literature include Keri, Nivea, Aquaphor, and Eucerin (Arndt, 1983). The drawback to these products is cost, availability, and the fact that bath oil may be hazardous to safety and become ineffective as it becomes suspended rather than absorbed (Epstein, 1983; Forth & Kapke, 1983).
Dermatologists, however, suggest multiple home products such as petrolatum, vegetable oil, lanolin, or mineral oil for treating dry skin (Arndt, 1983). Some debate exists about the efficacy of each: lanolin because it may sensitize skin (Parent, 1985), mineral oil because it may act as a drying agent (Pearson & Kotthof, 1979), and vegetable oil because it may leave an odor (Epstein, 1983). While these products are easily accessible, the choice of emollient in treating dry skin requires further research. Lanolin is more expensive than either mineral oil or petrolatum while baby oil (fragranced mineral oil) is less expensive than mineral oil. Because of its economic nature, because of its effectiveness reported in the literature, and because it has been tested empirically by Brown and colleagues (1982), mineral oil was seen as the agent of choice in this research. Petrolatum, although potentially very effective as an occlusive agent, may be considered unappealing to the client who is concerned with staining clothing (Dotz & Berman, 1984; Parent, 1985). The nurse and client must evaluate the effectiveness and desirability of products.
The consensus is that 90° to 105° water temperature be used in treating dry skin (Arndt, 1983; Dotz & Berman, 1984; Fitzsimmons, 1983; Hogstel, 1983; Forth & Kapke, 1983; Pearson & Kotthof, 1979). This is generally not a problem in institutions where controls are placed on water temperature that prevent scalding and maintain water temperature between 90° and 105°. However, home management of dry skin may require the use of a water thermometer if moderate temperature water is difficult for an individual to gauge.
Although the maintenance of sufficient environmental humidity is suggested by nearly everyone addressing the subject of dry skin, some variance in the ideal level is reported. Dry skin is common at humidities of <30% and uncommon at humidities >60% although Hogstel (1983) reported finding humidities ranging from 25% to 40% in one nursing home. The majority of authors state that humidity should be maintained at over 60% in order for treatments for dry skin to be effective (Gaul & Underwood, 1951; Hogstel, 1983). Room temperature should be kept as low as is comfortable to prevent further drying as dry heat in the winter contributes to further drying (Arndt, 1983). In private homes the use of humidifiers or pans of water on radiators or, where possible, humidifiers installed in forced-air systems, will increase humidity (Arndt, 1983; Walther & Harber, 1984). In institutional settings, central environmental controls may have such humidifying elements, may need to be added, or may require adjustment. Obviously subjects with a higher humidity in this study fared better with the intervention.
Four studies testing interventions for dry skin have previously been reported in the literature. Spoor (1958) analyzed the effects of a water-dispersable bath oil in the treatment of patients with "dry, itchy, scaly, lichenified skin" (p. 3299) and reported successful therapeutic affect and "personal acceptance" in 10 of 12 subjects. Weiner et al. (1973) tested a nationwide sample of 153 persons over age 50 and reported limited success in the treatment of dry skin with a topical moisturizing and lubricating lotion. Brown and colleagues (1982) showed significant (p<.01) improvement in foot dryness using 10minute water soaks followed by mineral oil application in 31 longterm care residents. Hardy (199Oa) reported statistically significant results in a pilot study of 15 institutionalized elders with a mean age of 70 years who used a bathing protocol for dry skin. The present study, however, adds significantly to the nursing practice literature because it provides an analysis of the effects of a practical bathing treatment done with a heterogeneous sample of older subjects and measures the interactive effects of mode and frequency of bathing.
Limitations of this study include the sample size and lack of random assignment. The size of this convenience sample is inadequate for generalizability of findings. Many subjects withdrew for personal reasons and many declined to participate because of their skepticism of research despite the noninvasiveness of this protocol and the large population of elderly individuals with dry skin. Some declined to participate after seeing the dermatologist but admitted that the fact they could see one for free had been an incentive to agree to being considered for the study. The lack of random assignment and the possibility of rater bias limits the generalizability of the findings.
Bathing is a very important element of self-care and one in which nurses have a critical role in all settings: hospitals, nursing homes, home care, and outpatient care. This study has limitations. However, the tested protocol is consistent with the advice of dermatologists and resulted in findings that support the use of a bathing treatment for dry skin. This nursing intervention offers practicing nurses some important options to test in treating clients with dry skin.
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Summary of Statistical Probabilities fp) of Variables In Study
Optimal Combination at Factors That Effectively Tteat Dry Skin