New England Journal of Medicine 352: 2314-2324 June 2, 2005 Number 22
Hywel C. Williams, Ph. D., Atopic Dermatitis
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Treatment:
Topical Corticosteroids
One systematic review identified 83 randomized controlled trials of the use of topical corticosteroids in atopic dermatitis.30 Vehicle-controlled studies lasting less than one month indicate that approximately 80 percent of people report good, excellent, or clear responses with topical corticosteroids, whereas 38 percent of persons in control groups reported such responses.
Potency of topical corticosteroids is classified by the potential for vasoconstriction — a surrogate for clinical efficacy and skin thinning (Table 3). In general, only preparations that have very weak or moderate strength are used on the face and genital area, whereas those that have moderate or potent strength are used on other areas of the body.31 Lower-potency corticosteroids may be sufficient on all areas of the body in younger children. Preparations are typically used in bursts of three to seven days in order to achieve control. There is little difference in outcome between short-term use of potent preparations or longer use of weaker preparations in children with mild-to-moderate disease.32 Lichenified atopic dermatitis requires more potent preparations for longer periods.
Long-term studies of moderate-to-potent preparations in children are scarce. One study of 231 children with stabilized atopic dermatitis randomly assigned to receive twice-weekly 0.05 percent fluticasone propionate (plus emollients) or vehicle alone plus emollients for 16 weeks showed that patients in the control group were more likely, by a factor of 8, to have a relapse (95 percent confidence interval, 4.3 to 15.2).33 A four-month trial of persons 12 to 64 years of age with moderate-to-severe disease showed that the application of fluticasone to previously active and new sites of atopic dermatitis for two consecutive days each week reduced flares significantly, as compared with a group receiving an emollient only.
Reduced efficacy of topical corticosteroids may be related to disease severity rather than to glucocorticoid resistance.35 There is little evidence that the application of topical corticosteroids twice a day is more effective than once-daily applications,36 and more frequent use may cause more local side effects.
A main concern with the use of topical corticosteroids is irreversible skin thinning. Although thinning is possible, the concern on the part of patients (and parents) is often well out of proportion to the true risk.37 Although inappropriate use of potent preparations can cause skin thinning, four 16-week randomized trials did not show any clinically significant skin thinning,32,33,34,38 and a 1-year study showed no significant effect on collagen synthesis.39 A one-year study of unrestricted continual use of a potent corticosteroid on the limbs and trunk, a weak preparation on the face, or both showed that striae developed in 3 of 330 adults with moderate-to-severe atopic dermatitis.40 Similar studies in children are lacking. Other possible side effects of corticosteroids include facial telangiectasia and glaucoma from periocular use (rarely reported in adults).
Secondary adrenal suppression and the suppression of growth resulting from systemic absorption of topical corticosteroids are also concerns, although clinically relevant adrenal suppression is very rare.41 One study involving children with atopic dermatitis did not find any relationship between height velocity and the use of mild-potency as compared with moderate-potency topical corticosteroids.42 Another study showed biochemical evidence of suppression of the hypothalamic–pituitary–adrenal axis only in children with atopic dermatitis who used potent or very potent topical corticosteroids and in those who had received glucocorticoids from other routes, and not in those who had used topical corticosteroids of mild or moderate strength for a median of 6.9 years.
Emollients
There is no evidence that emollients improve atopic dermatitis directly. However, emollients are widely used because they improve the appearance and symptoms of the dry skin (xerosis) associated with this condition.30,31,43 One study has shown that emollients may reduce the need for topical corticosteroids by approximately 50 percent,44 and another study found that emollients enhanced the response to treatment with topical corticosteroids.45 There is little basis for suggesting the use of one emollient over another, and the preference of the patient is probably the most important factor.
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