Five-Year Adjuvant Endocrine Therapy Adherence Trajectories Among Women With Breast Cancer: A Nationwide French Study Using Administrative Data

• Published in: Clinical breast cancer Vol. 21; no. 4; pp. e415 - e426
• Main Authors: Lailler, Grégory, Memoli, Victoria, Le Bihan Benjamin, Christine, Ben Diane, Marc-Karim, Lauzier, Sophie, Mancini, Julien, Bousquet, Philippe Jean, Bouhnik, Anne-Déborah
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2021; Elsevier
• Subjects: Adult; Age Factors; Aged; Antineoplastic Agents, Hormonal; Antineoplastic Agents, Hormonal - therapeutic use; Breast cancer; Breast Neoplasms; Breast Neoplasms - drug therapy; Breast Neoplasms - psychology; Cancer Survivors; Cancer Survivors - psychology; Cancer Survivors - statistics & numerical data; Chemotherapy, Adjuvant; Cohort Studies; Epidemiology; Estrogen Antagonists; Estrogen Antagonists - therapeutic use; Female; France; Group-based trajectory modeling; Hormone therapy; Humanities and Social Sciences; Humans; Mastectomy; Medication Adherence; Medication Adherence - statistics & numerical data; Middle Aged; Pharmaco-epidemiology; Statistics; Tamoxifen; Tamoxifen - therapeutic use; France; Medication adherence; Pharmaco-epidemiology; Breast cancer; Group-based trajectory modeling; Hormone therapy; Epidemiology
• ISSN: 1526-8209; 1938-0666; 1938-0666
• DOI: 10.1016/j.clbc.2021.01.007

Adjuvant endocrine therapy (AET) improves long-term survival of breast cancer patients, yet many women are nonadherent or discontinue this treatment. In this study we aimed to describe AET adherence trajectories over 5 years after treatment initiation and to identify factors associated with these trajectories, in a nationwide French cohort of breast cancer survivors. Every woman diagnosed with a first nonmetastatic breast cancer in 2011 in France who initiated AET in the 12 months after surgery was included from the French cancer cohort. We identified all reimbursements for AET from national health administrative data sets and modeled AET adherence trajectories over 5 years, using group-based trajectory modeling on the basis of the monthly proportion of days covered by AET. Associated factors were identified using multinomial logistic regressions. We included 33,260 women. A 6-trajectory model was selected: 1, immediate discontinuation (6.6%); 2, continuous suboptimal adherence (4.3%); 3, progressive nonadherence then discontinuation (6.3%); 4, early nonadherence then discontinuation (5.7%); 5, continuous optimal adherence (68.8%); and 6, late nonadherence then discontinuation (8.3%). The main factors associated with nonadherence trajectories were extreme age (younger than 50 and older than 70 years) and switching AET. Approximately 70% of women had optimal adherence over all 5 years. The original nationwide approach enabled us to identify the “continuous suboptimal adherence trajectory” never previously described. •A large proportion of women are nonadherent to adjuvant endocrine therapy.•Seventy percent of women will have optimal adherence for 5 years.•Extreme age categories and switching adjuvant endocrine therapy were associated with nonadherence trajectories.•Four percent of women followed a “continuous suboptimal adherence trajectory,” previously unidentified in the literature. This study aimed to describe adjuvant endocrine therapy adherence trajectories over 5 years and to identify factors associated with these trajectories, in a nationwide French cohort of breast cancer survivors. Among the 33,260 women included, 23,202 (68.8%) had a continuous optimal adherence trajectory. The main factors associated with nonadherence trajectories were extreme age (younger than 50 and older than 70 years) and switching adjuvant endocrine therapy.