Various factors, including extent of disease and nail involvement, predict worse therapeutic outcomes in patients with alopecia areata (AA) undergoing contact immunotherapy with diphenylcyclopropenone or squaric acid dibutyl ester. Results of the systematic review and meta-analysis were published in JAMA Dermatology.
The investigators sought to summarize the clinical outcomes associated with the use of contact immunotherapy for AA based on standardized criteria for hair regrowth and several prognostic factors, with defined criteria for therapeutic hair regrowth and regrowth rate having been highly heterogeneous across studies in the past.
Clinical trials or observational studies that explored the use of contact immunotherapy for AA, subgrouped the disorder into patchy alopecia or alopecia totalis/universalis, and reported hair regrowth rates were included in the analysis. The main outcome was hair regrowth rate, based on the 4-grade criteria for therapeutic regrowth. Secondary outcomes were incidence of treatment-related adverse effects and recurrence rates.
Overall, a total of 45 studies that included 2227 patients were evaluated. The overall rate of any hair regrowth was 65.5% among those with AA, with rates of 74.6% in those with patchy alopecia and 54.5% in those with alopecia totalis/universalis. The complete regrowth rate was 32.3%; 24.9% in patients with patchy alopecia, and 32.3% in patients with alopecia totalis/universalis.
Disease extent of ≥50%, according to the Severity of Alopecia Tool (odds ratio [OR] 3.05; 95% CI, 2.26-4.11), atopic history (OR 1.61; 95% CI, 1.03-2.50), and nail involvement (OR 2.06; 95% CI, 1.26-3.36) were all linked with poorer therapeutic outcomes. The rate of recurrence was 38.3% in patients who received maintenance therapy vs 49.0% in those not receiving any maintenance therapy.
The investigators concluded that because many factors are associated with hair regrowth outcomes after the use of contact immunotherapy, quantitative summarization may help improve patient education, thus leading to enhanced therapeutic adherence and hair regrowth outcomes. Patients with AA need to receive accurate information based on personal prognostic factors and level of anticipated therapeutic outcomes.
Lee S, Kim BJ, Lee YB, Lee W-S. Hair regrowth outcomes of contact immunotherapy for patients with alopecia areata: a systematic review and meta-analysis. JAMA Dermatol. 2018;154(10):1145-1151.