The severity of atopic dermatitis and quality of life can be improved comparably by sublingual and subcutaneous immunotherapy to aeroallergens, notably home dust mite.

The purpose of a systematic review and meta-analysis was to compile data on the advantages and disadvantages of allergen immunotherapy (AIT) for atopic dermatitis.

Databases such as Web of Science, Global Resource for Eczema Trials, LILACS, CINAHL, CENTRAL, EMBASE, and MEDLINE were searched for randomized controlled trials contrasting sublingual immunotherapy (SLIT), subcutaneous immunotherapy (SCIT), or/and no AIT (standard care or placebo) for the following patient-important outcomes as defined by the guideline panel: adverse events, atopic dermatitis severity, flares, atopic dermatitis-related quality of life (QoL), and itch.

Screening, extraction and assessment of risk of bias was done. The intervention effects were synthesized utilizing frequentist and Bayesian random-effects models. The evidence quality was evaluated utilizing GRADE approach.

A total of 23 randomized controlled studies incorporating 1957 pediatric and adult subjects exposed predominantly to home dust mites revealed that SLIT and SCIT as an adjunct had comparable absolute and relative effects and are likely to result in significant improvements in atopic dermatitis severity, determined by a 50% decline in SCORing Atopic Dermatitis (risk ratio 1.53; 26% vs. 40%, absolute difference 14%) and QoL, determined by an enhancement in the Dermatology Life Quality Index (DLQI) by ≥ 4 points (risk ratio 1.44; 39% vs 56%, absolute difference 17%; both outcomes were of moderate certainty).

Both AIT delivery routes raised the probability of adverse events (risk ratio 1.61; 66% with SCIT vs. 41% with placebo; 13% with SLIT vs. 8% with placebo; high certainty). The impact of AIT on eczema flares and sleep disturbances remained mostly unknown. Sensitivity and subgroup analysis supported the main outcomes.

Both SLIT and SCIT to aeroallergens, especially home dust mites, can significantly reduce atopic dermatitis severity and improve QoL of patients. Compared to SLIT, SCIT elicits more adverse events.