Adherence to adjuvant hormone therapy (AHT) in early breast cancer (BC)

• Published in: Journal of clinical oncology Vol. 31; no. 15_suppl; p. e11522
• Main Authors: Lohmann, Ana, Al Barrak, Jasem, Peixoto, Renata D'Alpino, Chen, Leo, Cheung, Winson Y.
• Format: Journal Article
• Language: English
• Published: 20.05.2013
• ISSN: 0732-183X; 1527-7755
• DOI: 10.1200/jco.2013.31.15_suppl.e11522

Abstract only e11522 Background: Randomized controlled trials of early BC consistently demonstrate a survival benefit from AHT. Some studies show that adherence to AHT is suboptimal, but data are conflicting. There are concerns that poor adherence can negatively impact survival. We conducted a systematic review to evaluate adherence to AHT in early BC and clinical factors associated with non-adherence. Methods: Using search terms such as 'adherence', ‘adjuvant treatment’ and ‘breast cancer’, we identified a total of 843 articles published between 1990 and 2012 of which 43 met our eligibility criteria (7 prospective and 36 retrospective). Pooled estimates of adherence and non-adherence were derived by random effects models. Heterogeneity was assessed by the Cochran's Q and I-squared statistics. To detect for potential publication bias, Egger’s test was conducted. Results: The median rates of adherence, compliance, continuation and persistence to AHT were 77%, 79%, 69% and 81%, respectively. Compared to individuals aged <60 years, patients aged >/=60 years had a significantly higher likelihood of non-adherence (RR 1.59, 95% CI 1.27-2.00, p<0.001). Likewise, non-white patients were more likely to poorly adhere to AHT when compared to their white counterparts (RR 1.39, 95% CI 1.00-1.94, p=0.05). Additionally, prior or concurrent receipt of chemotherapy (RR 1.41, 95% CI 1.06-1.88, p=0.018) and radiation (RR 1.79, 95% CI 1.14-2.81, p=0.011) were independently associated with worse adherence. Interestingly, those with more than a moderate income level defined as >$30,000 per annum had a greater likelihood of poor adherence to AHT when compared to low income earners (RR 1.12, 95% CI 1.01-1.24, p<0.024). There was moderate to high heterogeneity across studies, but there was no evidence of publication bias. Conclusions: In this systematic review, adherence rates to AHT for early BC were suboptimal, underscoring the importance of increased vigilance and need for strategies that promote compliance with proven therapies. Poor adherence patterns were observed in specific patient subsets, but these were not limited to only marginalized populations. Prospective trials of adherence interventions that stratify by these patient subgroups are warranted.