The etiology of atopic dermatitis (AD) involves the complex interplay between genetics, immune dysregulation, and environmental factors that disrupt the epidermis and lead to erythematous, crusted, and pruritic lesions.¹ The prevalence of AD has been increasing worldwide, now affecting as many as 30% of children and 10% of adults in their lifetime.² This chronic disorder, often beginning in infancy, is associated with various negative health outcomes, including sleep disruptions, anxiety, depression, cardiovascular disease, and suicidality.^3-5

Atopic dermatitis is currently treated with a combination of emollients, topical corticosteroids, and other anti-inflammatory agents, wet wraps, anti-bacterial agents, and control of triggering factors, such as environmental allergens and irritants.⁶ While these therapies can help achieve disease control, challenges with consistent adherence due to regimen complexity, cost, side effects, and time constraints are common.⁷,⁸ Additionally, the current standard treatments for AD do not fully address the cognitive and behavioral aspects of the disorder, which play a significant role in the aforementioned impact on morbidity. Because of this, promising multidisciplinary interventions are being trialed for patients with AD. In this review, we focus on one approach called Habit Reversal Therapy (HRT) and examine the evidence and the potential clinical implications.

Targeting Habitual Behaviors

Cognitive Behavioral Therapy (CBT) is a form of psychological treatment that utilizes a structured, goal-oriented approach to modify distressing emotions, thoughts, and behaviors. The foundation of CBT is built upon the notion that these three domains (emotions, thoughts, and behaviors) are all interconnected, and thus, altering one can have a decisive influence on the remaining two, (Figure 1). Following this, CBT has proven to be therapeutic for many psychiatric disorders, including depression, anxiety, obsessive-compulsive disorders, and addictions. However, it is also an option for treating physical conditions, such as chronic pain and rheumatism.⁹

Figure 1: The CBT Triad

There is a growing body of evidence that supports the use of CBT for AD because behavioral aspects of the disorder, such as scratching, become habitual.^10-12 One key symptom of AD is chronic itch, a psychophysiological sensation that can be intense and unrelenting. This can lead to scratching, which damages the skin barrier and leads to stimulation and sensitization of sensory fibers as well as inflammation. Together, this increases itching, which results in further scratching.¹³ Because scratching diminishes the immediate sensation of pruritis (but simultaneously can damage the skin barrier and worsen inflammation in the skin), the scratching behavior is positively reinforced, creating a vicious cycle. Awareness of the scratching behavior diminishes over time and patients can condition themselves to scratch their skin, even in the absence of pruritus and active AD lesions. The behavior can thus become generalized to multiple situations, especially when exposed to an event that would typically lead to an increase in itching, such as preparing to shower.¹² Triggers can also be associated with negative emotions, such as anxiety or depressed mood, and can lead to avoidance of social situations, which prompts the development and worsening of comorbidities.¹⁰ These triggering events can occur hundreds of times a day, leading to a subconscious, self-perpetuating scratch cycle that significantly reduces the chances of appropriate skin healing and prolongs the impact of the condition. Behavioral treatment, therefore, targets this aversive conditioned response, as shown in Figure 2, by providing tools to enhance scratching awareness and training in how to refrain from scratching when exposed to triggering events to further improve quality of life and disease control.^10-12 This specific form of CBT is known as Habit Reversal Therapy (HRT).

Figure 2: Habit Reversal Intervention

how hrt can help in treating AD

Habit reversal therapy has been used for quite some time and has amassed some persuasive evidence of its efficacy. Multiple case reports have demonstrated the potential benefits of targeting habitual maladaptive behaviors with reduction strategies.^14-18 The first formal characterization of HRT took place in 1973 in a case study that involved 12 participants.¹⁸ The study investigated nervous habits, such as onychophagia, thumb sucking, and shoulder jerking, and sought to bring awareness to the actions to limit their practice. In a single treatment session, the investigators introduced the participants to competing responses that were incompatible with the original nervous habit. The habits did not return during the extended follow-up for 11 participants.¹⁸

In the 1980s, HRT was formally introduced as a treatment for habitual scratching in AD, demonstrating significant reductions in self-reported scratching and improvement in self-reported skin status.¹⁹ This habit-reversal technique was later combined and studied with optimal topical treatment in a method known as the Combined Approach, which focused on the patient learning how to treat themselves.^20,21 The first of two studies involved 17 individuals with AD. All participants were instructed to keep track of the frequency of their scratching episodes, along with the associated circumstances for scratching. After collecting this data for one week, the participants were divided into two groups: hydrocortisone only and hydrocortisone plus HRT. Those in the HRT group were instructed to grasp an object or clench their fist in place of scratching their skin and were given praise for succeeding. Both groups demonstrated improvement; however, at the end of 4 weeks, the scratching frequency was reduced by 90% with the combined therapy in comparison to only 60% with hydrocortisone alone.²⁰ A second study of 46 individuals with AD was then performed that provided an alternative to the stimulus of itch, in addition to the scratching. Participants were now also instructed to pinch the skin where it was itching–which reduces the pruritus without causing damage–when grasping an object or clenching their fist was not sufficient to eliminate the itch. This study demonstrated a significant reduction in scratching frequency within three days of program initiation.²¹ Subsequently, within four weeks, skin healing progressed to a stage that allowed for reduction in the frequency of topical treatment in the majority of participants.²¹ However, no participants showed complete healing of their eczematous lesions by the end of the study, suggesting that longer periods of treatment with topical steroids were required.²¹ While these initial results are encouraging, both of these studies were performed in small populations with limited time frames, which makes it difficult to determine the true effect of HRT and how it would perform in a greater clinical setting due to the cyclical nature of the disorder.

Since these original studies were performed, the use of HRT and other CBT methodologies for the treatment of AD have been further investigated.^22-24 The most comprehensive study consisted of 137 participants with chronic AD, who were randomly assigned to a 12-week treatment program that consisted of standard medical care (SMC) or SMC in addition to either dermatological education (DE), cognitive-behavioral treatment (BT), combined dermatological and behavioral training (DEBT) or autogenic training (AT), a form of relaxation therapy. The DE program focused on informing participants about factors that influence AD and to train them in skin care, while the CBT program consisted of training on control of scratching, relaxation, and stress management. The combination of the two (DEBT), therefore, is most comparable to the original HRT program goals. Assessments taken 12 months after treatment initiation showed that, compared to those that only received SMC or DE, participants that received BT, DEBT, or AT experienced a significant improvement in skin lesions, with the greatest concomitant reduction in steroid use in the DEBT group, and reduction in AD-related stress.²² In addition, the DEBT group exhibited the greatest reduction in the severity of scratching and itching as well as anxiety at follow-up in comparison to the SMC group.²² These results demonstrate that psychological treatments are an important adjunct to SMC in the treatment of individuals with AD, especially when considering stable treatment effects, and programs that aim to reduce scratching behavior specifically may provide an additional benefit to patients. Various other studies have been performed that attempt to reinforce these results but they are limited by small sample sizes, short study durations, confounders, or inability to calculate effect magnitude (shown in Table 1.)^25-28

Virtual HRT: Is It Feasible?

Despite the need for further research and more sophisticated methodologies to quantify outcomes, the potential benefits of HRT in terms of scratching frequency, itch intensity, and topical steroid utilization are promising. Additional benefits of HRT are that specialist psychological training is not required for treatment and sessions may be delivered remotely. Because it can effectively be delivered online, HRT has the potential to enhance treatment accessibility and decrease time spent traveling to appointments, while requiring minimal provider resources. A randomized clinical trial investigated the utility of this method by enrolling 102 adults with AD into a 12-week care plan that included either internet-delivered exposure and response prevention with standard care or just standard care.¹⁰ The remote treatment consisted of 10 instructive online modules and was monitored by four licensed psychologists who specialized in CBT. It was found that the group that received remote CBT had a greater weekly reduction in AD symptoms and perceived stress, sleep difficulties, and depressive symptoms from baseline and that the treatment led to stable improvements at 6- and 12-month follow-up appointments.¹⁰ These results demonstrate that delivering CBT via the internet can yield meaningful clinical improvements for patients with AD who may otherwise be unable to engage in routine in-person treatment and can potentially help address some of the challenges of treating patients with chronic AD.

Summary

There is still a need for effective and accessible therapies that address the cognitive and behavioral aspects of AD to maximize the probability of achieving disease control. It is evident that utilizing HRT as an adjunctive therapy has the potential to significantly reduce the scratching habit. As a result, HRT also has the potential to break the scratch cycle, thereby promoting more rapid skin healing, decreasing reliance on topical medications, and lessening the overall burden of the disorder. Further studies, however, are needed in larger populations with sufficient time frames to fully investigate the outcomes of individuals that are treated with a combination of HRT and topical treatments. While there is a need for further high-quality research to explore HRT, this is an approach that can be offered to patients with AD who have unmet needs and are interested in trying to improve their symptoms with self-directed behavior change.

The authors have no relevant financial disclosures to report.

1. Frazier W, Bhardwaj N. Atopic dermatitis: Diagnosis and treatment. Am Fam Physician. 2020;101(10):590-598. https://www. ncbi.nlm.nih.gov/pubmed/32412211

2. Kolb L, Ferrer-Bruker SJ. Atopic Dermatitis. StatPearls Publishing; 2022. Accessed January 22, 2023. https://www.ncbi.nlm. nih.gov/books/NBK448071/

3. Yaghmaie P, Koudelka CW, Simpson EL. Mental health comorbidity in patients with atopic dermatitis. J Allergy Clin Immunol. 2013;131(2):428-433. doi:10.1016/j.jaci.2012.10.0414. Silverwood RJ, Forbes HJ, Abuabara K, et al. Severe and predominantly active atopic eczema in adulthood and long term risk of cardiovascular disease: population based cohort study. BMJ. 2018;361:k1786. doi:10.1136/bmj.k1786

5. Sandhu JK, Wu KK, Bui TL, Armstrong AW. Association between atopic dermatitis and suicidality: A systematic review and meta-analysis. JAMA Dermatol. 2019;155(2):178-187. doi:10.1001/jamadermatol.2018.4566

6. Eichenfield LF, Tom WL, Berger TG, et al. Guidelines of care for the management of atopic dermatitis: section 2. Management and treatment of atopic dermatitis with topical therapies. J Am Acad Dermatol. 2014;71(1):116-132. doi:10.1016/j.jaad.2014.03.023

7. Su JC, Kemp AS, Varigos GA, Nolan TM. Atopic eczema: its impact on the family and financial cost. Arch Dis Child. 1997;76(2):159-162. doi:10.1136/adc.76.2.159

8. Spielman SC, LeBovidge JS, Timmons KG, Schneider LC. A review of multidisciplinary interventions in atopic dermatitis. J Clin Med Res. 2015;4(5):1156-1170. doi:10.3390/jcm4051156

9. Cognitive Behavioral Therapy. Institute for Quality and Efficiency in Health Care (IQWiG); 2016. Accessed January 27, 2023. https://www.ncbi.nlm.nih.gov/books/NBK279297

10. Hedman-Lagerlöf E, Fust J, Axelsson E, et al. Internet-delivered cognitive behavior therapy for atopic dermatitis: A randomized clinical trial. JAMA Dermatol. 2021;157(7):796-804. doi:10.1001/jamadermatol.2021.1450

11. Jordan JM, Whitlock FA. Atopic dermatitis anxiety and conditioned scratch responses. J Psychosom Res. 1974;18(5):297-299. doi:10.1016/0022-3999(74)90047-6

12. Daunton A, Bridgett C, Goulding JMR. Habit reversal for refractory atopic dermatitis: a review. Br J Dermatol. 2016;174(3):657659. doi:10.1111/bjd.14176

13. Capec S, Petrek M, Capec G, Yaremkevych R, Andrashko Y. Psychologic interventions in patients with the chronic dermatologic itch in atopic dermatitis and psoriasis: A step forward with family constellations seminars. Front Med. 2022;9:965133. doi:10.3389/fmed.2022.965133

14. Allen KE, Eileen Allen K, Harris FR. Elimination of a child’s excessive scratching by training the mother in reinforcement procedures. Behav Res Ther. 1966;4(1-2):79-84. doi:10.1016/0005-7967(66)90046-5

15. Watson DL, Tharp RG, Krisberg J. Case study in self-modification: Suppression of inflammatory scratching while awake and asleep. J Behav Ther Exp Psychiatry. 1972;3(3):213-215. doi:10.1016/0005-7916(72)90077-8

16. Dobes RW. Amelioration of psychosomatic dermatosis by reinforced inhibition of scratching. J Behav Ther Exp Psychiatry. 1977;8(2):185-187. doi:10.1016/0005-7916(77)90045-3

17. Shah R, Bewley A. The importance of integrated psychological interventions and dedicated psychologists in dermatology. Clin Exp Dermatol. 2014;39(3):428-430. doi:10.1111/ced.12282

18. Azrin NH, Nunn RG. Habit-reversal: a method of eliminating nervous habits and tics. Behav Res Ther. 1973;11(4):619-628. doi:10.1016/0005-7967(73)90119-8

19. Rosenbaum MS, Ayllon T. The behavioral treatment of neurodermatitis through habit-reversal. Behav Res Ther. 1981;19(4):313-318. doi:10.1016/0005-7967(81)90052-8

20. Melin L, Frederiksen T, Noren P, Swebilius BG. Behavioural treatment of scratching in patients with atopic dermatitis. Br J Dermatol. 1986;115(4):467-474. doi:10.1111/j.1365-2133.1986.tb06241.x

21. Norén P. Habit reversal: a turning point in the treatment of atopic dermatitis. Clin Exp Dermatol. 1995;20(1):2-5. doi:10.1111/j.1365-2230.1995.tb01273.x

22. Ehlers A, Stangier U, Gieler U. Treatment of atopic dermatitis: a comparison of psychological and dermatological approaches to relapse prevention. J Consult Clin Psychol. 1995;63(4):624-635. doi:10.1037//0022-006x.63.4.624

23. Chida Y, Steptoe A, Hirakawa N, Sudo N, Kubo C. The effects of psychological intervention on atopic dermatitis. Int Arch Allergy Immunol. 2007;144(1):1-9. doi:10.1159/000101940

24. Lavda AC, Webb TL, Thompson AR. A meta-analysis of the effectiveness of psychological interventions for adults with skin conditions. Br J Dermatol. 2012;167(5):970-979. doi:10.1111/j.1365-2133.2012.11183.x

25. Staab D, Diepgen TL, Fartasch M, et al. Age-related, structured educational programmes for the management of atopic dermatitis in children and adolescents: multicentre, randomised controlled trial. BMJ. 2006;332(7547):933-938. doi:10.1136/ bmj.332.7547.933

26. van Os-Medendorp H, Ros WJG, Eland-de Kok PC, et al. Effectiveness of the nursing programme “Coping with itch”: a randomized controlled study in adults with chronic pruritic skin disease. Br J Dermatol. 2007;156(6):1235-1244. doi:10.1111/j.13652133.2007.07919.x

27. Evers AWM, Duller P, de Jong EMGJ, et al. Effectiveness of a multidisciplinary itch-coping training programme in adults with atopic dermatitis. Acta Derm Venereol. 2009;89(1):57-63. doi:10.2340/00015555-0556

28. Norén P, Hagströmer L, Alimohammadi M, Melin L. The positive effects of habit reversal treatment of scratching in children with atopic dermatitis: a randomized controlled study. Br J Dermatol. 2018;178(3):665-673. doi:10.1111/bjd.16009