Adherence to oral endocrine treatments in women with breast cancer: can it be improved?

Abstract

There is a perception that women on oral endocrine treatments for oestrogen receptor-positive breast cancer will be adherent to these medicines, as they are facing a serious life-threatening disease, and the oral endocrine treatments are effective, easy to use and generally well tolerated. This is not in fact the case, and this is the basis of the first half of this review. The second half is of whether the changes/interventions to 'improve' adherence do actually increase adherence to the oral endocrine medicines. The review shows that better outcomes are achieved with good adherence to endocrine treatments in breast cancer. The rates of adherence to endocrine treatments range between 15 and 50%, and are influenced by a large number of factors (e.g. adverse effects, lack of belief in treatment, psychological problems and poor patient-health care provider relationship). Interventions to minimise the adverse effects have been used in an attempt to improve the adherence to the endocrine treatment therapies, but it is not known whether these do actually improve adherence. Similar, it has been assumed that interventions by health professionals (doctors, nurses and pharmacists) will improve the adherence, but this has not been tested. In conclusion, in women with breast cancer, we know there is a problem with adherence. There are also many approaches and suggestions about how to improve adherence to the oral endocrine treatments, but none of these approaches/suggestions have been scientifically tested, and they need to be.

Barriers and facilitators to endocrine therapy adherence among underserved hormone-receptor-positive breast cancer survivors: a qualitative study

“…The American Society of Clinical Oncology (ASCO) and National Comprehensive Cancer Network (NCCN) best practice guidelines recommend 5–10 years of adjuvant treatment with oral anti-hormonal medications (also known as hormonal or endocrine therapy) [4–6]. There are two main types of oral anti-hormonal medications: 1) Tamoxifen, a selective estrogen receptor modulator, recommended for both pre- and post-menopausal women; and 2) aromatase inhibitors (e.g., letrozole, anastrozole, exemestane), recommended for post-menopausal women only [7–9]. Regular anti-hormonal medication use is associated with decreased mortality related to cancer recurrence [4,5,10–12].…”

“…Side effects vary by medication and can include weight gain, joint pain, hot flashes, headaches, fatigue [19], decreased libido, mild arthritis, vaginal discharge, abdominal bloating, and bone density loss [15]. There is limited evidence regarding the efficacy of strategies for side effect management [9]. …”

“…Cost, however, may become less of a barrier as anti-hormonal medications become generic (as two of the medications are) and much less expensive [9,20]. Health system characteristics associated with decreased adherence or persistence include switching hormonal therapies and receiving follow-up care from a general practitioner rather than an oncologist [13].…”

Low Adherence to Upfront and Extended Adjuvant Letrozole Therapy among Early Breast Cancer Patients in a Clinical Practice Setting

“…Most studies assessing rates of adherence to AIs include a large proportion of patients on anastrozole [15,17,18]. In addition, a large cohort study demonstrated adherence to anastrozole in a routine clinical practice setting [12].…”

Psychological insulin resistance: scope of the problem

“…[7][8][9] Furthermore, among existing insulin users, adherence to the prescribed regimen is suboptimal in up to one third of patients. 10 Failure to initiate insulin therapy in a timely manner and to comply with the recommended injection doses and schedule are key factors that lead to low rates of glycaemic target attainment. Among participants of a multinational study that evaluated the quality of care of patients with diabetes in Asia, more than half of the enrolled patients did not reach the glycated haemoglobin (HbA1c) target of <7.0%, and the situation was worse in those with youngonset diabetes.…”