Study shows AD patients do not follow topical regimen

February 1, 2008

Adherence to topical treatment with one of three different formulations of a mid-potency corticosteroid was explored in a prospective, randomized, investigator-blinded study enrolling adult patients with atopic dermatitis. The results highlight that nonadherence is a common problem and linked to treatment success.

Key Points

Washington - Results of a prospective, randomized study evaluating treatment of adult atopic dermatitis (AD) patients with different formulations of a topical mid-potency corticosteroid reaffirm that poor adherence is a significant clinical problem as well as a predictor of treatment success, according to Steven R. Feldman, M.D., Ph.D., professor of dermatology, pathology and public health sciences, Wake Forest University School of Medicine, Winston-Salem, N.C.

The study enrolled 15 patients who were randomized to apply the ointment, cream or lipocream formulations of hydrocortisone 17-butyrate 0.1 percent (Locoid, Ferndale Laboratories) twice daily for two weeks to all AD lesions.

Patients were told adherence was being monitored, but they were unaware it was being done electronically with a microprocessor in the container cap.

Study findings

Despite the generally mediocre adherence, disease severity improved significantly based on three investigator-blinded assessments: the Investigator's Global Assessment (IGA), Eczema Area and Severity Index, and target plaque severity scores.

However, the rate of treatment success (i.e., IGA score of clear or almost clear) was twofold higher among the adherent patients compared with those who were non-adherent (62.5 versus 33.3 percent).

"Non-adherence, rather than non-response, is likely the underlying factor for insufficient treatment response of atopic dermatitis and other dermatologic and non-dermatologic disorders.

"Our findings underline the importance of involving patients in treatment decisions. If you prescribe a medication they will use, the treatment will likely be much more successful," Dr. Feldman says.

Adherence issues

Dr. Feldman notes that the observed adherence in this clinical trial is better than that occurring in daily practice. Not only did the study have a short duration, but patients who consent to participate in a clinical study are probably more motivated than typical patients.

"In fact, in a study we recently published, we found abysmal adherence among children with atopic dermatitis being treated with a corticosteroid ointment, whose parents were not aware medication use was being monitored. Mean adherence over eight weeks was only 32 percent, and in some children, adherence dropped to that level within the first several days," he says.

Medication formulations

The data from the prospective, randomized study of the three formulations of hydrocortisone 17-butyrate is being analyzed for possible associations between the individual vehicles and adherence, although it is not expected that this study has the power to identify statistically significant differences.

Experience from clinical practice, however, indicates individual patients have definite preferences for different vehicles that should be explored prior to prescribing.

"One of the first concepts taught in dermatology residency is to use an ointment to treat a dry, scaly rash, but if the patient finds a greasy vehicle objectionable, efforts to force its use are probably counterproductive.

"Greater emphasis needs to be given to incorporating patient preferences into therapeutic decisions. Having multiple vehicles from which to choose may help clinicians to better tailor treatment and thereby improve adherence and treatment success," Dr. Feldman says.

Disclosure: The study was supported by funding from Ferndale Laboratories. Dr. Feldman has received funding from many companies that manufacture products used in the treatment of dermatologic disease.