title: Effect of selective serotonin reuptake inhibitors use on endocrine therapy adherence and breast cancer mortality: a population-based study.
abstract: The purpose of the study was to investigate whether the concomitant use of selective serotonin reuptake inhibitors (SSRI) with tamoxifen influences the risk of death due to breast cancer, and we also investigated the association between SSRI use and adherence to oral endocrine therapy (ET). We analyzed data from BCBaSe Sweden, which is a database created by the data linkage of Registries from three different regions of Sweden. To investigate the association between ET adherence and SSRI use, we included all women who were diagnosed with non-distant metastatic ER-positive invasive breast cancer from July 2007 to July 2011 and had at least one dispensed prescription of oral tamoxifen or aromatase inhibitor. To investigate the role of concurrent administration of SSRI and tamoxifen on breast cancer prognosis, we performed a nested case-control study. In the adherence cohort, 9104 women were included in the analyses. Women who received SSRI, either before or after breast cancer diagnosis, were at higher risk for low adherence to ET. However, when the overlapping period between SSRI use and ET was >50 %, no excess risk for low adherence was observed. Non-adherence (<80 %) to ET was significantly associated with worse breast cancer survival (OR 4.07; 95 % CI 3.27-5.06). In the case-control study, 445 cases and 11125 controls were included. The concomitant administration of SSRI and tamoxifen did not influence breast cancer survival, neither in short-term (OR 1.41; 95 % CI 0.74-2.68) nor in long-term SSRI users (OR 0.85; 95 % CI 0.35-2.08). Concomitant SSRI and tamoxifen use does not seem to increase risk for death due to breast cancer. Given the positive association between continuing antidepressive pharmacotherapy for a longer period of time and adherence to ET, it is essential to capture and treat depression in breast cancer patients to secure adherence to ET.
authors: Centre for Clinical Research Sörmland, Uppsala University, 63188, Eskilstuna, Sweden. antonis.valachis@igp.uu.se.
authors: Antonis
authors: A
authors: Valachis
authors: Division of Cancer Studies, Cancer Epidemiology Unit, School of Medicine, King's College London, London, UK.
authors: Hans
authors: H
authors: Garmo
authors: Institute of Pharmaceutical Science, King's College London, London, SE1 9NH, UK.
authors: John
authors: J
authors: Weinman
authors: Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
authors: Irma
authors: I
authors: Fredriksson
authors: Department of Oncology, Faculty of Medicine and Health, University of Örebro, Örebro, Sweden.
authors: Johan
authors: J
authors: Ahlgren
authors: Department of Surgical and Perioperative Sciences, Umeå University, 901 85, Umeå, Sweden.
authors: Malin
authors: M
authors: Sund
authors: Division of Cancer Studies, Cancer Epidemiology Unit, School of Medicine, King's College London, London, UK.
authors: Lars
authors: L
authors: Holmberg
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000150:complications / Q000188:drug therapy / Q000401:mortality*; D016022:Case-Control Studies; D003863:Depression / Q000188:drug therapy* / Q000401:mortality; D005260:Female; D006801:Humans; D009864:Ontario; D017374:Paroxetine / Q000009:adverse effects* / Q000627:therapeutic use; D010349:Patient Compliance; D012189:Retrospective Studies; D017367:Selective Serotonin Reuptake Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D013629:Tamoxifen / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D018931:Antineoplastic Agents, Hormonal; D017374:Paroxetine; D017367:Selective Serotonin Reuptake Inhibitors; D013629:Tamoxifen
keywords: Adherence; Breast cancer; Endocrine therapy; Prognosis; SSRI; Tamoxifen