Adherence to adjuvant endocrine therapy in postmenopausal breast cancer patients: A 5-year prospective study

Kari Britt Hagen; Turid Aas; Jan Terje Kvaløy; Håvard Søiland; Ragna Lind

doi:10.1016/j.breast.2019.01.003

Adherence to adjuvant endocrine therapy in postmenopausal breast cancer patients: A 5-year prospective study

Breast. 2019 Apr:44:52-58. doi: 10.1016/j.breast.2019.01.003. Epub 2019 Jan 8.

Authors

Kari Britt Hagen¹, Turid Aas², Jan Terje Kvaløy³, Håvard Søiland⁴, Ragna Lind⁵

Affiliations

¹ Department of Breast and Endocrine Surgery, Haukeland University Hospital, Bergen, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway. Electronic address: kari.britt.hagen@helse-bergen.no.
² Department of Breast and Endocrine Surgery, Haukeland University Hospital, Bergen, Norway. Electronic address: turid.aas@helse-bergen.no.
³ Research Department, Stavanger University Hospital, Stavanger, Norway; Department of Mathematics and Physics, University of Stavanger, Stavanger, Norway. Electronic address: jan.t.kvaloy@uis.no.
⁴ Department for Breast and Endocrine Surgery, Stavanger University Hospital, Stavanger, Norway; Department of Clinical Science, University of Bergen, Bergen, Norway. Electronic address: hsoiland@gmail.com.
⁵ Department of Clinical Medicine, University of Bergen, Bergen, Norway; Department of Medicine, Haukeland University Hospital, Bergen, Norway. Electronic address: ragna.lind@helse-bergen.no.

PMID: 30641300
DOI: 10.1016/j.breast.2019.01.003

Abstract

Purpose: Adjuvant endocrine therapy (ET) in breast cancer reduces recurrence risk and increases overall survival. The aim of the study was to quantify non-adherence and discontinuation to ET in postmenopausal women with breast cancer, and identify possible clinical or social risk factors.

Methods: Women with hormone-receptor positive breast cancer (N = 138), mean age 58 (SD 9.3) years, filled in 4 questionnaires within 1-12, 24, 36 and 48-60 months after surgery; Subjective Health Complaints Inventory (SHC), Functional Assessment of Cancer Therapy-Social Support Subscale (FACT-ES), and Quality of Patient Information Questionnaire (QPI). Adherence to Tamoxifen (Tam) or Aromatase Inhibitors (AI) was examined using self-reported adherence and data from the Norwegian Prescription Database (NorPD) [corrected]. Kaplan-Meier curves and Cox proportional hazards regression models estimated adherence to ET.

Results: The estimate of discontinued ET within 60 months was 38%. Self-reported discontinuation was 7% compared with 25% from the NorPD. Being overweight or obese were significantly time dependent factors predictive for discontinuing ET, p = 0.025.

Conclusion: Closer follow-ups, tailor-made information about the proven benefits of ET, and keeping a normal body mass index (BMI) may improve adherence to ET in postmenopausal women with breast cancer.

Keywords: Adherence; Adjuvant endocrine therapy; Body mass index; Breast cancer; Self-reported health complaints.

MeSH terms

Antineoplastic Agents, Hormonal / therapeutic use*
Aromatase Inhibitors / therapeutic use*
Breast Neoplasms / drug therapy*
Chemotherapy, Adjuvant
Female
Humans
Medication Adherence / statistics & numerical data*
Middle Aged
Obesity / complications
Patient Compliance
Postmenopause
Prospective Studies
Receptors, Estrogen / analysis
Receptors, Progesterone / analysis

Substances

Antineoplastic Agents, Hormonal
Aromatase Inhibitors
Receptors, Estrogen
Receptors, Progesterone