Systematic review of real‐world persistence and adherence in subcutaneous allergen immunotherapy

Abstract

Background Given that subcutaneous immunotherapy (SCIT) adherence in the literature is often studied in closely monitored trials, few studies report real‐world SCIT adherence. The purpose of this review is to assess SCIT adherence in real‐world settings. Methods A literature search of PubMed, Embase, Cochrane Library, Web of Science, and Scopus for real‐world studies examining SCIT adherence was performed. Paired investigators independently reviewed all articles. For this review, “persistence” was defined as continuing therapy and not being lost to follow‐up after initiating SCIT, and “adherence” defined as persistence in accordance with prescribed SCIT dose, dosing schedule, and duration. Article quality was first assessed using a modified Newcastle‐Ottawa scale and then converted to Agency for Healthcare Research and Quality standards (good, fair, and poor). Results The search yielded 1596 nonduplicate abstracts, from which 17 articles (n = 263,221 patients) met inclusion criteria. Fourteen (82%) studies reported persistence rates, ranging from 16.0% to 93.7%. Seven (41%) studies reported adherence rates, ranging from 15.1% to 99%. Five (29%) studies (n = 416 patients) collected original data on reasons for discontinuing SCIT, of which inconvenience was most cited. All studies were Oxford level of evidence 2b and of good (n = 10) to fair (n = 7) quality. Conclusion Real‐world SCIT persistence and adherence rates are poor, with the majority of included studies reporting rates <80%; however, they range widely, explained in part by inter‐study differences in measuring and reporting adherence‐related findings. Future studies on SCIT adherence may benefit from following concordant definitions of persistence and adherence in addition to standardized reporting metrics.

Sublingual immunotherapy persistence and adherence in real‐world settings: A systematic review

“…Most literature reviews of AIT adherence report wide‐ranging values and do not necessarily limit analysis to real‐world studies 8,50,51 . Similar to our prior review of SCIT adherence, 10 our systematic review of SLIT only includes adherence studies conducted in real‐world settings, outside of strictly controlled clinical trials which are not necessarily reflective of patient behavior in regular clinical care. Our systematic review also attempted to subclassify SLIT adherence‐related data as either persistence data or adherence data.…”

“…The purpose of this systematic review was to assess SLIT adherence in real‐world studies. In a prior systematic review, we assessed real‐world adherence to SCIT, which requires that treatment be administered by or under the supervision of a healthcare provider 10 . SLIT is known to be of similar efficacy to SCIT 11 ; however, SLIT is inherently different from SCIT in that it often requires more frequent maintenance doses (e.g., daily administration as opposed to monthly) and can be self‐administered from home.…”

Diagnosis and Management of Insect Allergy: Barriers and Facilitators in the United States

“…Five of the studies reviewed with a total of 416 patients cited "inconvenience" as the primary reason for discontinuation. 61 Kiel et al 62 studied levels and predictors of compliance and persistence of aeroallergen SCIT in the Netherlands from 1994 to 2009. Only 23% of patients completed the recommended minimum 3 years of maintenance aeroallergen SCIT in that period.…”

“…Five of the studies reviewed with a total of 416 patients cited “inconvenience” as the primary reason for discontinuation. 61 …”

“… 66 More recently, Park et al completed a military multi-site study of patients who underwent fire ant SCIT and postulated that lack of adherence could be due to this population’s high relocation rate and barriers associated with transition of care. 61 More active monitoring and system-level facilitation of venom immunotherapy may be needed.…”