Influence of adherence to adjuvant endocrine therapy on disease-free and overall survival: a population-based study in Catalonia, Spain

Adherence to Adjuvant Endocrine Therapy in Patients With Nonmetastatic Estrogen Receptor-Positive Breast Cancer: A Comprehensive Brazilian Real-World Data Study

PURPOSE

Adjuvant endocrine therapy (ET) improves the prognosis of patients with nonmetastatic estrogen receptor-positive (ER+) breast carcinoma; however, adherence is crucial to ensure its efficacy. In Brazil, data regarding adherence to ET are limited. We aimed to evaluate the adherence to ET across Brazil and the characteristics associated with adherence.

METHODS

Women with nonmetastatic ER+ invasive breast carcinoma who underwent ET for at least 6 months were enrolled. Adherence was assessed using the Morisky Medication Adherence Scale-8 (MMAS-8) and defined as an MMAS-8 score of 8. The groups were compared using the chi-square or exact chi-square tests for qualitative variables and the nonparametric Mann-Whitney test for quantitative variables.

RESULTS

Between June 2021 and September 2023, 726 patients were included in this analysis. The adherence to ET was 58.7%. The median age of the adherent women was higher than that of the nonadherent women (58.3 years v 54.8 years; P = .009). Factors associated with adherence were nonuse of ovarian suppression (P = .004), use of anti-human epidermal growth factor receptor 2 therapy (P = .007), high European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire C30 scores on global health status (P = .0004), role functioning (P = .03), emotional functioning (P = .0007), cognitive functioning (P < .001), and social functioning (P = .0005), and EORTC BR23 scores on body image (P < .001) and future perspective domains (P = .0198).

CONCLUSION

More than one third of the patients evaluated were not adherent to ET. Although the study did not assess the impact of interventions to improve adherence to adjuvant ET, the 58.7% adherence rate shows that this study is of utmost importance.

Group-Based Trajectory Modeling to Identify Patterns and Predictors of Adherence to Oral Endocrine Therapies in Underserved Population of Greater Houston Area

Background

Poor adherence to oral endocrine therapy (OET) is a significant problem among patients with hormone receptor-positive breast cancer as it results in higher risk of recurrence and mortality. Non-adherence to OET is prevalent among underserved patients, often attributable to socioeconomic factors and limited healthcare access. We evaluated OET adherence patterns over time using group-based trajectory modeling (GBTM) and identified predictors of suboptimal adherence trajectory among patients seen at Harris Health System, serving underserved patients in Houston, Texas.

Methods

A single-center, retrospective study was conducted from October 2019 through December 2020. OET adherence was measured using proportion of days covered (PDC). A logistic GBTM was conducted using 2-5 adherence groups considering the Bayesian information criteria, clinical relevance, and a 5% minimum membership requirement. Multinomial logistic regression was used to assess the predictors of non-adherence trajectories.

Results

Among 496 patients, majority were Hispanic (62.50%) or African American (15.12%) and <65 years of age (82.66%). Four distinct adherence trajectories were identified: consistent high adherence (41.4%); constant PDC at ~0.6 (32.6%); rapid decline (14.6%); low adherence with gradual decline (11.5%). African Americans had higher likelihood of having low adherence with gradual decline [odds ratio (OR): 2.462 (confidence interval (CI): 1.1149-5.276), p=0.0205]. Patients with diabetes were more likely to have constant PDC at ~0.6 [OR: 1.714 (CI: 1.042-2.820), p=0.0338]. Longer time (4 or greater years) on therapy predicted low adherence with gradual decline [OR: 2.463 (CI: 1.266-4.793), p=0.008) and constant PDC at ~0.6 (OR: 1.966 (CI: 1.141-3.388), p=0.0149] trajectories.

Conclusion

The identified predictors, including comorbidities like diabetes, African American descent, and longer OET treatment are crucial considerations when developing patient-centered interventions to enhance OET adherence among underserved populations. These insights can guide the implementation of initiatives such as mobile health applications, community-based educational programs, and financial aid efforts.

Evaluating the Quality of Real-World Data on Adherence to Oral Endocrine Therapy in Breast Cancer Patients: How Real Is Real-World Data?

PURPOSE

The aim of this study was to compare estimates of adherence to oral endocrine therapy (OET) based on real-world data (RWD) and on clinical evaluation in people diagnosed with breast cancer in the public healthcare system in Catalonia (Spain).

METHODS

We conducted two retrospective cohort studies. Cohort 1 (RWD) consisted of women diagnosed with breast cancer in 2021 in the public healthcare system of Catalonia (Spain). Sources of RWD were the pharmacy billing register, hospital discharge records, and the Catalan health division's central insurance registry. Nonadherence was defined as below 80% adherence in the first year of treatment. Data for cohort 2 came from two population-based cancer registries in Girona and Tarragona (Catalonia), with diagnoses from 2007 to 2011. We evaluated the impact of variables missing from RWD, such as stage and hormonal status. Analyses were performed using a chi-square test and logistic regression, with results stratified by age group and drug type.

RESULTS

Nonadherence at one year was 10.9% in cohort 1 and 11.3% in cohort 2. When we reviewed the medical records of a selection of nonadherent women from cohort 1, we found only 59.4% had documented treatment interruptions. Reasons for interruptions in the patients from RWD cohort included adverse effects (48.8%), patient decision (40.0%), medical reasons (29.4%), and other clinical causes (14.7%). Women aged under 50 years and those receiving tamoxifen or a sequential regimen had lower adherence. Determinants associated with nonadherence were similar in both approaches used.

CONCLUSIONS

This study confirms the validity of estimating adherence with RWD from the Spanish national health system, although when combined with reviewing medical records, this may provide more reliable and higher-quality data. The RWD method provides valuable evidence to help oncologists discuss adherence with their patients.

A Preoperative Window-of-Opportunity Study of Oral SERD, Imlunestrant, in Newly Diagnosed ER-Positive, HER2-Negative Early Breast Cancer: Results from the EMBER-2 Study

PURPOSE

Imlunestrant is an oral selective estrogen receptor degrader with favorable safety and preliminary efficacy in patients with advanced breast cancer. Pharmacodynamic (PD) biomarker data can optimize drug dosing; in this study, we present PD data from the EMBER-2 study.

PATIENTS AND METHODS

Postmenopausal women with untreated, operable estrogen receptor (ER)-positive, HER2-negative early breast cancer were randomized to 400 versus 800 mg of imlunestrant daily for ∼2 weeks before surgery. A single arm study tested a daily dose of 200 mg. PD biomarker changes (ER, progesterone receptor, Ki-67 by IHC, and mRNA expression of ER-related genes) were evaluated in paired tumor samples (pre-/posttreatment). Safety and pharmacokinetics were also assessed.

RESULTS

Among evaluable paired samples (n = 75), PD profiles demonstrated consistent ER targeting between 400- and 800-mg doses, with less toxicity at the 400-mg dose. Although inducing the lowest rate of complete cell-cycle arrest, PD and pharmacokinetic results were similar for the 200-mg dose.

CONCLUSIONS

EMBER-2 combined with existing phase I data has identified 400 mg as the optimal imlunestrant dose.

Association between trajectories of adherence to endocrine therapy and risk of treated breast cancer recurrence among US nonmetastatic breast cancer survivors

BACKGROUND

Endocrine therapy is the mainstay treatment for breast cancer (BC) to reduce BC recurrence risk. During the first year of endocrine therapy use, nearly 30% of BC survivors are nonadherent, which may increase BC recurrence risk. This study is to examine the association between endocrine therapy adherence trajectories and BC recurrence risk in nonmetastatic BC survivors.

METHODS

This retrospective cohort study included Medicare beneficiaries in the United States (US) with incident nonmetastatic BC followed by endocrine therapy initiation in 2010-2019 US Surveillance, Epidemiology, and End Results linked Medicare data. We calculated monthly fill-based proportion of days covered in the first year of endocrine therapy. We applied group-based trajectory models to identify distinct endocrine therapy adherence patterns. After the end of the first-year endocrine therapy trajectory measurement period, we estimated the risk of time to first treated BC recurrence within 4 years using Cox proportional hazards models.

RESULTS

We identified 5 trajectories of adherence to endocrine therapy in BC Stages 0-I subgroup (n = 28,042) and in Stages II-III subgroup (n = 7781). A trajectory of discontinuation before 6 months accounted for 7.0% in Stages 0-I and 5.8% in Stages II-III subgroups, and this trajectory was associated with an increased treated BC recurrence risk compared to nearly perfect adherence (Stages 0-I: adjusted hazard [aHR] = 1.84, 95% CI = 1.46-2.33; Stages II-III: aHR = 1.38, 95% CI = 1.07-1.77).

CONCLUSIONS

Nearly 7% of BC survivors who discontinued before completing 6 months of treatment was associated with an increased treated BC recurrence risk compared to those with nearly perfect adherence among Medicare nonmetastatic BC survivors.

Digging in real-word electronic database for assessing CDK 4/6 inhibitors adherence in breast cancer patients from Romania

Introduction: It is imperative for patients to respect the prescribed treatments to achieve the anticipated clinical outcomes, including the outpatients receiving oral anti-cancer drugs such as selective cyclin-dependent kinase 4/6 inhibitors (CDK 4/6i). With the introduction of three CDK 4/6i drugs in the Romanian pharmaceutical market in 2018, our study aimed to evaluate medication adherence and the influencing factors among patients undergoing treatment with palbociclib, ribociclib, or abemaciclib for advanced or metastatic breast cancer. Methods: Medication adherence was assessed using the Proportion of Days Covered (PDC) method, and Spearman correlation analysis was conducted to explore the relationships between adherence, age, gender, and follow-up duration. Results: The study enrolled 330 breast cancer patients, with an average follow-up period of 14.6 ± 12.5 months for palbociclib, 10.6 ± 7.1 months for ribociclib, and 8.6 ± 6.4 months for abemaciclib-treated patients. A small proportion of patients demonstrated non-adherence: 12.8% for palbociclib, 14.6% for ribociclib, and 14.7% for abemaciclib. Among patients receiving palbociclib, there was no significant correlation between adherence, age (rho = 0.07, p = 0.35), or gender (rho = -0.144, p = 0.054). However, a significant correlation was found with the duration of follow-up (rho = -0.304, p < 0.0001). Similar results were observed for patients receiving ribociclib or abemaciclib. Most patients received combination therapy with letrozole (46%) and exemestane (13%) for palbociclib, letrozole (48%) and fulvestrant (19%) for ribociclib, and fulvestrant (39%) and letrozole (27%) for abemaciclib, Discussion: High adherence rates were observed among patients treated with CDK 4/6i drugs, with no significant differences noted among the three drugs in this class. However, the collected patient data was limited, lacking information on adverse reactions that could potentially lead to treatment discontinuation, as determined by the oncologist's decision not to prescribe. Consequently, a comprehensive understanding of all factors contributing to the low adherence levels is hindered.

The Impact of the COVID-19 Pandemic on Adherence to Endocrine Therapy for Breast Cancer in Catalonia (Spain)

Purpose. To assess the impact of the COVID-19 pandemic on adherence to oral endocrine therapy in patients diagnosed with breast cancer in the public healthcare system in Catalonia (Spain). Methods. Retrospective cohort study in patients starting endocrine therapy from 2017 to 2021. Adherence was measured during the first year of treatment, and the impact of the pandemic was calculated according to the calendar year and whether the first year of treatment included the peak period of the pandemic in our setting (March-September 2020). Analyses were performed using a chi-square test and multivariable logistic regression, with results stratified by year, age group, and drug type. Results. Mean overall adherence during the first year of treatment was 89.6% from 2017 to 2021. In contrast, the patients who started treatment in 2019 and 2020 and whose treatment included the peak pandemic period presented an adherence of 87.0% and 86.5%, respectively. Young age and tamoxifen or combination therapy were predictors of low adherence. An increase in neoadjuvant therapy was also observed in 2020. Conclusions. The COVID-19 pandemic had only a modest impact on adherence to endocrine therapy (≈3%), despite the enormous disruptions for patients, the healthcare system in general, and cancer care in particular that were occurring in that period.

Beliefs about medicines' association with endocrine therapy adherence in early breast cancer survivors in Croatia

This observational, cross-sectional study conducted at the University Hospital Centre Zagreb (UHC Zagreb) aimed to explore patients' beliefs about adjuvant endocrine therapy (AET) as well as their association with non-adherence and sociodemographic and clinical factors. Out of 420 early breast cancer (BC) patients included in the study, 79.5 % perceived AET necessary and important for their health, as measured by the Belief About Medicines Questionnaire (BMQ), with the mean necessity score (20.4 ± 3.68) significantly higher than the mean concerns score (13 ± 4.81) (p < 0.001). Based on the Medication Adherence Report Scale (MARS-5), 44.4 % (n = 182) of the participants were non-adherers, out of which 63.2 % (n = 115) were unintentional and 36.8 % (n = 67) intentional non-adherers. Significantly higher concern beliefs were found among patients that were younger (p < 0.001), employed (p < 0.001), intentionally non-adherent to AET (p = 0.006), had a lower body-mass index (p = 0.005) and a higher level of education (p < 0.001), were premenopausal at the time of diagnosis (p < 0.001), taking tamoxifen treatment (p = 0.05) and receiving ovarian suppression (p < 0.001). Younger patients should be recognized as being at risk of non-adherence as they hold greater concern beliefs about medicines.

Adherence to and persistence with adjuvant hormone therapy, healthcare utilization, and healthcare costs among older women with breast cancer: A population-based longitudinal cohort study

INTRODUCTION

To assess associations between adherence to and persistence with adjuvant hormone therapy, healthcare utilization, and healthcare costs among older women with breast cancer.

MATERIALS AND METHODS

This study was a population-based longitudinal cohort study using the Surveillance, Epidemiology, and End Results (SEER) registry linked with Medicare claims. This study included older women diagnosed with stage I-III hormone receptor-positive breast cancer from 2009 through 2017. Participants were considered adherent with a proportion of days covered (PDC) of 0.80 or more and persistent if they had no hormone therapy discontinuation, i.e., a break of at least 180 continuous days. Length of persistence was calculated as time from therapy initiation to discontinuation. All participants were followed for up to five years after hormone therapy initiation. Generalized linear mixed models with repeated measures or hurdle generalized linear mixed models in the event of excess zeroes were used to assess associations between adherence to and persistence with annual healthcare utilization and costs.

RESULTS

This study included 25,796 women. Being adherent was associated with lower annual healthcare utilization, i.e., hospitalizations, hospital days, emergency room visits, and hospital outpatient visits. Persistence was associated with fewer annual hospitalizations, hospital days, emergency room visits, and hospital outpatient visits. Adherent participants had lower annual inpatient costs, outpatient costs, medical costs, and total healthcare costs despite higher prescription drug costs. Both being persistent and longer persistence were associated with lower inpatient costs, outpatient costs, medical costs, and total healthcare costs despite higher prescription drug costs.

DISCUSSION

This study underscores the economic benefits associated with adherence to and persistence with adjuvant hormone therapy based on comprehensive measures for healthcare utilization and costs. To our best knowledge, this was the first study that reported total healthcare cost savings associated with adherence to and persistence with adjuvant hormone therapy.

Importance of endocrine treatment adherence and persistence in breast cancer survivorship: a systematic review

PURPOSE

Adjuvant endocrine treatment is essential for treating luminal subtypes of breast cancer, which constitute 75% of all breast malignancies. However, the detrimental side effects of treatment make it difficult for many patients to complete the guideline-required treatment. Such non-adherence may jeopardize the lifesaving ability of anti-estrogen therapy. In this systematic review, we aimed to assess the consequences of non-adherence and non-persistence from available studies meeting strict statistical and clinical criteria.

METHODS

A systematic literature search was performed using several databases, yielding identification of 2,026 studies. After strict selection, 14 studies were eligible for systematic review. The review included studies that examined endocrine treatment non-adherence (patients not taking treatment as prescribed) or non-persistence (patients stopping treatment prematurely), in terms of the effects on event-free survival or overall survival among women with non-metastatic breast cancer.

RESULTS

We identified 10 studies measuring the effects of endocrine treatment non-adherence and non-persistence on event-free survival. Of these studies, seven showed significantly poorer survival for the non-adherent or non-persistent patient groups, with hazard ratios (HRs) ranging from 1.39 (95% CI, 1.07 to 1.53) to 2.44 (95% CI, 1.89 to 3.14). We identified nine studies measuring the effects of endocrine treatment non-adherence and non-persistence on overall survival. Of these studies, seven demonstrated significantly reduced overall survival in the groups with non-adherence and non-persistence, with HRs ranging from 1.26 (95% CI, 1.11 to 1.43) to 2.18 (95% CI, 1.99 to 2.39).

CONCLUSION

The present systematic review demonstrates that non-adherence and non-persistence to endocrine treatment negatively affect event-free and overall survival. Improved follow-up, with focus on adherence and persistence, is vital for improving health outcomes among patients with non-metastatic breast cancer.

Persistence with tamoxifen and aromatase inhibitors in Germany: a retrospective cohort study with 284,383 patients

PURPOSE

The aim of this study was to analyze the persistence of women on tamoxifen (TAM) and aromatase inhibitors (AIs) in Germany, and to investigate possible determinants of non-persistence.

METHODS

The present retrospective cohort study was based on the IQVIA longitudinal prescription database (LRx). The study included women with an initial prescription of TAM or AIs (anastrozole, letrozole, and exemestane) between January 2016 and December 2020 (index date). Kaplan-Meier analyses were performed to show the persistence for TAM and AI, using a therapy gap of 90 or 180 days, respectively. A multivariable Cox proportional hazards regression model was further used to estimate the relationship between non-persistence and drug prescription (AI versus TAM), age, and the specialty of the physician initiating therapy (gynecologist, oncologist, or general practitioner).

RESULTS

Up to 5 years after the index date, only 35.1% of AI and 32.5% of TAM patients were continuing therapy when therapy discontinuation was defined as at least 90 days without therapy. Using a 180-day therapy gap, 51.9% of AI and 50.4% of TAM patients remained on therapy after 5 years. Cox regression models reveal that initial therapy with TAM (HR 1.06, 95% CI 1.04-1.07), therapy initiation by oncologists (HR 1.09, 95% CI 1.07-1.11), or general practitioners (HR 1.24, 95% CI 1.21-1.27) and age ≤ 50 (HR 1.08, 95% CI 1.06-1.10) were significantly associated with an increased risk of therapy discontinuation.

CONCLUSION

Overall, the present study indicates that persistence rates are low in all age groups for both TAM and AI treatment. We found several factors (e.g., physician specialty, younger age, and type of endocrine therapy) to be associated with an increased risk for non-persistence.

Survival benefits associated with being adherent and having longer persistence to adjuvant hormone therapy across up to five years among U.S. Medicare population with breast cancer

PURPOSE

To assess associations between adherence to and persistence with adjuvant hormone therapy and mortality among older women with breast cancer.

METHODS

The surveillance, epidemiology, and end results data linked with U.S. Medicare claims was used. This study included older women diagnosed with stage I-III hormone receptor-positive breast cancer from 2009 through 2017. Adherence was defined as having proportion of days covered (PDC) ≥ 0.80. Persistence was defined as having no discontinuation, i.e., no break of ≥ 180 continuous days. Length of persistence was calculated as time from therapy initiation to discontinuation. Cox models with time-dependent covariates were used to assess associations between adherence and persistence with mortality.

RESULTS

This study included 25,796 women. Adherence rates were 78.1 percent, 75.2 percent, 72.4 percent, 70.0 percent, and 61.5 percent from year 1 to year 5 after hormone therapy initiation. Persistence rates were 87.5 percent, 81.7 percent, 77.1 percent, 72.9 percent, and 68.9 percent through cumulative intervals of 1 year up to 5 years. Adherence was associated with all-cause mortality but not associated with breast cancer-specific mortality. Persistent women had lower risk of all-cause mortality and breast cancer-specific mortality. Each additional year of persistence had additional contributions to survival benefits (11% decreased risk of all-cause mortality and 37% decreased risk of breast cancer-specific mortality).

CONCLUSION

This study confirms the detrimental effect of nonadherence to adjuvant hormone therapy across up to 5 years on all-cause survival in older U.S. women. It also reveals the survival benefits associated with having longer persistence across up to 5 years.

Adherence to endocrine therapy in early breast cancer in relation to Cytochrome P450 2D6 genotype: a comparison between pharmacy dispensation data and medical records

PURPOSE

Suboptimal adherence to adjuvant endocrine treatment (AET) is an important clinical concern. A correlation between CYP2D6 activity and tamoxifen discontinuation has been described. The main aim of this study was to investigate the consistency between pharmacy dispensation data and medical records on adherence to AET.

METHODS

Adherence was calculated for patients with at least 4.5 years of follow up and was defined as Medical Possession Rate ≥ 80%. Subgroup analyses were performed based on menopausal status, recurrence risk and CYP2D6 activity.

RESULTS

In 86% of the 1235 included patients the consistency between the two sources of information was within 80-125%. Poor consistency, < 80%, was most frequent in the premenopausal/ high-risk group and CYP2D6 Poor Metabolizers (PMs). Among 899 patients with at least 4.5 years follow up, 72% were adherent to tamoxifen based on pharmacy dispensation data, compared with 77% as reported by medical records. When including patients who switched to aromatase inhibitors after tamoxifen, adherence increased to 82% and 88%, respectively. Adherence did not differ by menopausal status or risk for recurrence. CYP2D6 PMs had poorer adherence (54%) to tamoxifen compared to patients with the highest CYP2D6 activity (83%).

CONCLUSIONS

There was a good consistency between medical records and pharmacy dispensing data on the use of AET. Adherence to AET was adequate, especially when including switch to aromatase inhibitors. Surprisingly, CYP2D6 PMs had low adherence to tamoxifen, despite a likely reduced risk of side effects according to previous data.

Informing interventions to improve uptake of adjuvant endocrine therapy in women with breast cancer: a theoretical-based examination of modifiable influences on non-adherence

PURPOSE

To inform intervention development, we measured the modifiable determinants of endocrine therapy (ET) non-adherence in women with breast cancer, using the Theoretical Domains Framework (TDF) and examined inter-relationships between these determinants and non-adherence using the Perceptions and Practicalities Approach (PAPA).

METHODS

Women with stages I-III breast cancer prescribed ET were identified from the National Cancer Registry Ireland (N = 2423) and invited to complete a questionnaire. A theoretically based model of non-adherence was developed using PAPA to examine inter-relationships between the 14 TDF domains of behaviour change and self-reported non-adherence. Structural equation modelling (SEM) was used to test the model.

RESULTS

A total of 1606 women participated (response rate = 66%) of whom 395 (25%) were non-adherent. The final SEM with three mediating latent variables (LVs) (PAPA Perceptions: TDF domains, Beliefs about Capabilities, Beliefs about Consequences; PAPA Practicalities: TDF domain, Memory, Attention, Decision Processes and Environment) and four independent LVs (PAPA Perceptions: Illness intrusiveness; PAPA Practicalities: TDF domains, Knowledge, Behaviour Regulation; PAPA External Factors: TDF domain, Social Identity) explained 59% of the variance in non-adherence and had an acceptable fit (χ²(334) = 1002, p < 0.001; RMSEA = 0.03; CFI = 0.96 and SRMR = 0.07) Knowledge had a significant mediating effect on non-adherence through Beliefs about Consequences and Beliefs about Capabilities. Illness intrusiveness had a significant mediating effect on non-adherence through Beliefs about Consequences. Beliefs about Consequences had a significant mediating effect on non-adherence through Memory, Attention, Decision Processesg and Environment.

CONCLUSIONS

By underpinning future interventions, this model has the potential to improve ET adherence and, hence, reduce recurrence and improve survival in breast cancer.

Adherence to Adjuvant Endocrine Therapy and Survival Among Older Women with Early-Stage Hormone Receptor-Positive Breast Cancer

BACKGROUND AND OBJECTIVE

Although improving adherence to adjuvant endocrine therapies (AETs) is critical to ensure better patient outcomes, the evidence is still lacking on differences in 5-year AET adherence trajectories. This study aimed to estimate the time trend of adherence by the type of individual AET and the association of adherence to AETs with overall survival among older women with hormone receptor-positive breast cancer.

METHODS

This study used the Surveillance, Epidemiology, and End Results-Medicare database 2006-2016. We included women aged ≥ 65 years with newly diagnosed hormone receptor-positive breast cancer and who had initiated AET (anastrozole, letrozole, exemestane, or tamoxifen). Adherence to AETs was defined as the proportion of days covered that was calculated for the follow-up period (5 years). The overall survival time was defined as the time from the date of AET initiation to death. The linear mixed models with repeated measures were used to estimate the changes in adherence to AETs. The Cox proportional hazard model was used to assess the relationships (hazard ratio [HR] and 95% confidence interval [CI]) between adherence to AETs and death.

RESULTS

A total of 11,617 patients were included. Anastrozole was the most commonly used (n = 6,908), followed by letrozole (n = 2,586), tamoxifen (n = 1,750), and exemestane (n = 373). The mean (standard deviation) of proportion of days covered for 5 years was 57.4 (34.6), indicating the highest proportion of days covered in the anastrozole group [61.1 (34.1)] and the lowest proportion of days covered in the exemestane group [44.0 (35.1)]. Overall, adherence to AET decreased over the 5-year follow-up period in all AET groups, but the decrease in the tamoxifen group was steeper (42.3% decreased) compared with other AETs. Anastrozole, letrozole, and exemestane groups were associated with a lower risk of death compared with the tamoxifen group (HR = 0.80, 95% CI 0.71-0.89 for anastrozole; HR = 0.82, 95% CI 0.72-0.93 for letrozole; HR = 0.82, 95% CI 0.63-1.07 for exemestane).

CONCLUSIONS

Patients who initiated with tamoxifen had a steeper decrease in adherence over the 5 years compared with anastrozole, letrozole, and exemestane groups. Furthermore, higher adherence was associated with a decreased risk of mortality. Physicians should be cognizant of decreasing adherence over time and choose effective treatment options with minimal side-effect profiles to better support adherence by patients with breast cancer.

Predictors of adherence and the role of primary non-adherence in antihormonal treatment of breast cancer

BACKGROUND

Antihormonal treatment for hormone receptor (HR) positive breast cancer has highly beneficial effects on both recurrence rates and survival. We investigate adherence and persistence in this group of patients.

METHODS

The study population comprised 1192 patients with HR-positive breast cancer who were prescribed adjuvant antihormonal treatment from 2004 to 2013. Adherence was defined as a medical possession ratio (MPR) of ≥80.

RESULTS

Of the 1192 included patients, 903 (75.8%) were adherent and 289 (24.2%) were non-adherent. Primary non-adherence was seen in 101 (8.5%) patients. The extremes of age (< 40 and ≥ 80 years) were associated with poor adherence. Patients with metastasis to axillary lymph nodes and those who received radiotherapy and/or chemotherapy were more likely to be adherent. Better adherence was also shown for those who switched medication at 2 years after diagnosis. Primary non-adherence seems to be associated with cancers with a good prognosis.

CONCLUSION

Adherence to antihormonal therapy for breast cancer is suboptimal. Primary non-adherence occurs among patients with a relatively good prognosis. Non-adherent patients tend to terminate their antihormonal therapy in the initial part of the treatment period. Targeted interventions to improve adherence should be focused on the first part of the treatment period.

Systematic adaptation of the adherence improving self-management strategy to support breast cancer survivors' adherence to adjuvant endocrine therapy: An intervention mapping approach

OBJECTIVE

Non-adherence to adjuvant endocrine therapy (AET) for breast cancer leads to increased recurrence and mortality risk and healthcare costs. Evidence on feasible, effective AET adherence interventions is scarce. This paper describes the systematic adaptation of the cost-effective adherence improving self-management strategy (AIMS) for patients with HIV to AET for women after breast cancer treatment.

METHODS

We followed the intervention mapping protocol for adapting interventions by conducting a needs assessment, reviewing target behaviours and determinants, reassessing behaviour change methods and adapting programme content. Therefore, we performed a literature review, consulted behavioural theory and organised nine advisory board meetings with patients and healthcare professionals.

RESULTS

Non-adherence occurs frequently among AET users. Compared to HIV treatment, AET is less effective, and AET side effects are more burdensome. This drives AET treatment discontinuation. However, the key determinants of non-adherence are largely similar to HIV treatment (e.g. motivation, self-regulation and patient-provider relationship); therefore, most strategies in AIMS-HIV also seem suitable for AIMS-AET. Modifications were required, however, regarding supporting patients with coping with side effects and sustaining treatment motivation.

CONCLUSION

AIMS seems to be a suitable framework for adherence self-management across conditions and treatments. Intervention mapping offered a transparent, systematic approach to adapting AIMS-HIV to AET.

Patient experiences and views on pharmaceutical care during adjuvant endocrine therapy for breast cancer: A qualitative study

OBJECTIVE

The use of adjuvant endocrine therapy (AET) after primary treatment of hormone receptor-positive breast cancer reduces the risk of recurrence and mortality. However, non-adherence is still common. Limited consideration has been given to how users deal with AET and the role of pharmaceutical care. Therefore, this study aims to obtain insight into the needs and wishes of women using AET regarding pharmaceutical care and eHealth.

METHODS

This is a qualitative explorative study comprising semi-structured interviews (n = 16) and a focus group (n = 5) among women who use or used AET after primary early-stage breast cancer (EBC) treatment using a thematic analysis approach.

RESULTS

Three themes emerged from the interviews and focus group: (1) experiences with AET use, (2) experiences with provided information and (3) needs and wishes regarding pharmaceutical care. Most women were highly motivated to use AET and indicated to have received useful information on AET. However, many expressed a strong need for more elaborate tailored and timely provided information on AET. They acknowledged the accessibility of pharmacists but reported that currently, pharmacists are hardly involved in AET care. Several women considered eHealth useful to obtain counselling and reliable information.

CONCLUSION

Women need more comprehensive information and follow-up in primary setting after initial cancer treatments. A more elaborate role for the pharmacy and eHealth/mHealth, especially with regard to counselling on side effects and side effect management, could potentially improve pharmaceutical care.

Impact of Endocrine Therapy Adherence on Outcomes in Elderly Women with Early-Stage Breast Cancer Undergoing Lumpectomy Without Radiotherapy

BACKGROUND

National Comprehensive Center Network guidelines recommend radiotherapy (RT) omission in women age ≥ 70 years with estrogen receptor-positive (ER+), cN0, T1 tumors post-lumpectomy if they receive endocrine therapy (ET). However, little is known about the impact of poor adherence on locoregional recurrence (LRR) in elderly women forgoing RT.

METHODS

Women age ≥ 70 years with pT1-2 ER+ breast cancer undergoing lumpectomy without RT from 2004 to 2019 were identified from a prospectively maintained database. ET adherence, calculated as treatment duration over follow-up time up to 5 years, was determined by chart review. We compared clinicopathologic characteristics and rates of LRR between women with high adherence (≥ 80%), low adherence (< 80%), and no ET.

RESULTS

Of 968 women (27 bilateral cancers), adherence was high in 676 (70%) and low in 162 (17%); 130 (13%) took no ET. Younger age and use of aromatase inhibitor were associated with high adherence. On multivariable analysis, tumor size (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.03-2.68, p = 0.04) and high adherence (HR 0.13, 95% CI 0.07-0.26, p < 0.001) were significantly associated with LRR. At 53 months median follow-up, the 5-year rate of LRR was 3.1% (95% CI 2.4-3.9%) with high adherence, 14.7% (95% CI 11.7-17.7%) with low adherence, and 17.9% (95% CI 13.9-21.8%) with no ET (p < 0.01).

CONCLUSIONS

Although adherence to ET was high overall, in the 30% of women with low adherence or no ET, LRR rates were significantly increased. Counseling regarding the distinct toxicities of ET and RT can help patients choose the therapy to which they will likely adhere to.

Using population-based data to evaluate the impact of adherence to endocrine therapy on survival in breast cancer through the web-application BreCanSurvPred

We show how the use and interpretation of population-based cancer survival indicators can help oncologists talk with breast cancer (BC) patients about the relationship between their prognosis and their adherence to endocrine therapy (ET). The study population comprised a population-based cohort of estrogen receptor positive BC patients (N = 1268) diagnosed in Girona and Tarragona (Northeastern Spain) and classified according to HER2 status (+ / −), stage at diagnosis (I/II/III) and five-year cumulative adherence rate (adherent > 80%; non-adherent ≤ 80%). Cox regression analysis was performed to identify significant prognostic factors for overall survival, whereas relative survival (RS) was used to estimate the crude probability of death due to BC (P_BC). Stage and adherence to ET were the significant factors for predicting all-cause mortality. Compared to stage I, risk of death increased in stage II (hazard ratio [HR] 2.24, 95% confidence interval [CI]: 1.51–3.30) and stage III (HR 5.11, 95% CI 3.46–7.51), and it decreased with adherence to ET (HR 0.57, 95% CI 0.41–0.59). P_BC differences were higher in non-adherent patients compared to adherent ones and increased across stages: stage I: 6.61% (95% CI 0.05–13.20); stage II: 9.77% (95% CI 0.59–19.01), and stage III: 22.31% (95% CI 6.34–38.45). The age-adjusted survival curves derived from this modeling were implemented in the web application BreCanSurvPred (https://pdocomputation.snpstats.net/BreCanSurvPred). Web applications like BreCanSurvPred can help oncologists discuss the consequences of non-adherence to prescribed ET with patients.

Psychoeducation for breast cancer: A systematic review and meta-analysis

BACKGROUND

Psychoeducation has emerged as an intervention for women with breast cancer (BC). This meta-analysis evaluated the effectiveness of psychoeducation on adherence to diagnostic procedures and medical treatment, anxiety, depression, quality of life (QoL), and BC knowledge among patients with BC symptoms or diagnosis and BC survivors.

METHODS

A systematic literature search (in PubMed, Embase, PsycINFO and Cochrane) for randomised controlled trials (RCTs) comparing the effects of psychoeducation to control among patients with BC symptoms or diagnosis and BC survivors. Effects were expressed as relative risks (RRs) and standardized mean differences (SMDs) with their 95% confidence intervals.

RESULTS

Twenty-seven RCTs (7742 participants; 3880 psychoeducation and 3862 controls) were included. Compared with controls, psychoeducation had no significant effect on adherence to diagnostic procedures and medical treatment (RR 1.553; 95% CI 0.733 to 3.290, p = .16), but it significantly decreased anxiety (SMD -0.710, 95% CI -1.395 to -0.027, p = .04) and improved QoL with (SMD 0.509; 95% CI 0.096 to 0.923, p < .01). No effects were found for psychoeducation on depression (SMD -0.243, 95% CI -0.580 to 0.091, p = .14), or BC knowledge (SMD 0.718, 95% CI -0.800 to 2.236, p = .23).

CONCLUSION

We demonstrated that psychoeducation did not improve adherence to diagnostic procedures and treatment, depression and BC knowledge but was valuable for reducing anxiety and improving QoL. Future studies may explore the effectiveness of psychoeducation in promoting adherence across various types of cancer.

No Excess Mortality up to 10 Years in Early Stages of Breast Cancer in Women Adherent to Oral Endocrine Therapy: A Probabilistic Graphical Modeling Approach

Breast cancer (BC) is globally the most frequent cancer in women. Adherence to endocrine therapy (ET) in hormone-receptor-positive BC patients is active and voluntary for the first five years after diagnosis. This study examines the impact of adherence to ET on 10-year excess mortality (EM) in patients diagnosed with Stages I to III BC (N = 2297). Since sample size is an issue for estimating age- and stage-specific survival indicators, we developed a method, ComSynSurData, for generating a large synthetic dataset (SynD) through probabilistic graphical modeling of the original cohort. We derived population-based survival indicators using a Bayesian relative survival model fitted to the SynD. Our modeling showed that hormone-receptor-positive BC patients diagnosed beyond 49 years of age at Stage I or beyond 59 years at Stage II do not have 10-year EM if they follow the prescribed ET regimen. This result calls for developing interventions to promote adherence to ET in patients with hormone receptor-positive BC and in turn improving cancer survival. The presented methodology here demonstrates the potential use of probabilistic graphical modeling for generating reliable synthetic datasets for validating population-based survival indicators when sample size is an issue.

Prevalence and correlates of joint pain among Chinese breast cancer survivors receiving aromatase inhibitor treatment

BACKGROUND

Aromatase inhibitor (AI)-induced joint pain is a common toxicity of AI treatment. Although many studies have been conducted to examine the occurrence and severity of AI-induced joint pain in breast cancer survivors, none of the studies focused on the Chinese population with breast cancer. Given that the differences in cultural background and the genetic structure between Asians and Caucasians may contribute to different phenotypes of joint pain, this cross-sectional study was therefore conducted to examine the prevalence of AI-induced joint pain among Chinese breast cancer survivors receiving AI treatment and the correlates of pain.

METHODS

This cross-sectional study was conducted in a tertiary hospital in China. Breast cancer survivors undergoing AI treatment were recruited to complete the following questionnaires: a self-designed baseline data form, the Nordic Musculoskeletal Questionnaire (NMQ), the Brief Pain Inventory (BPI), the 36-Item Short Form Health Survey (SF-36), and the Functional Assessment of Cancer Therapy-Breast (FACT-B). Based on the assessment results of NMQ (if the participant indicated pain in specific body parts), participants were then invited to complete other questionnaires to specifically assess the joint symptoms, including the Oxford Knee Score (OKS), the Oxford Hip Score (OHS), the Michigan Hand Outcomes Questionnaire (MHQ), and the Manchester Foot Pain Disability Questionnaire (MFPDQ). Descriptive analysis was used to analyse participants' baseline data and the prevalence of pain. Stepwise multiple regression was used to identify the correlates of pain.

RESULTS

Four hundred and ten participants were analysed. According to the NMQ, 71.7% of the participants experienced joint symptoms in at least one joint, and the most frequently mentioned joint was knee (39.0%). The diagram in BPI indicated that 28.0% of the participants had the worst pain around knees. In patients with knee pain, the mean OKS score was 40.46 ± 6.19. The sub-scores of BPI for pain intensity and pain interference were 1.30 ± 1.63 and 1.24 ± 1.79, respectively. Patients' poorer physical well-being/functioning, previous use of AI treatment, presence of osteoarthritis, and receiving of physiotherapy were identified as four common correlates of greater severity of pain and pain interference (p < 0.05).

CONCLUSIONS

Chinese breast cancer survivors can experience joint pain at various locations, particularly knees. In addition to increasing the use of interventions for pain alleviation, a comprehensive assessment of survivors' conditions such as physical functioning, history of AI treatment, and presence of osteoarthritis should be emphasized to identify survivors who need more attention and tailored interventions.

Association between adherence to oral therapies in cancer patients and clinical outcome: A systematic review of the literature

AIMS

Adherence to therapy is a key factor in successful treatment. The aim of this systematic review is to assess the extent to which patients with better adherence to oral therapy have better clinical outcomes among cancer patients.

METHODS

All studies published in PubMed up to 20 October 2020, which considered the use of oral anticancer drugs for cancer patients and which correlated treatment adherence with a clinical outcome, were considered.

RESULTS

From the 42 studies considered in the systematic review, 14 were for oncological indications and 28 for haematological indications. There was considerable variance in calculation methods, outcomes considered, and in the definitions of adherence. However, it emerged that most studies reported a significant correlation between adherence to therapy and clinical outcome.

CONCLUSION

As adherence to therapy is a key factor in achieving a better clinical outcome, future studies with large samples, robust endpoints and the use of at least two methods of assessing adherence would be desirable in order to produce more robust evidence.

A Smartphone-Based App to Improve Adjuvant Treatment Adherence to Multidisciplinary Decisions in Patients With Early-Stage Breast Cancer: Observational Study

BACKGROUND

Multidisciplinary treatment (MDT) and adjuvant therapy are associated with improved survival rates in breast cancer. However, nonadherence to MDT decisions is common in patients. We developed a smartphone-based app that can facilitate the full-course management of patients after surgery.

OBJECTIVE

This study aims to investigate the influence factors of treatment nonadherence and to determine whether this smartphone-based app can improve the compliance rate with MDTs.

METHODS

Patients who had received a diagnosis of invasive breast cancer and had undergone MDT between March 2013 and May 2019 were included. Patients were classified into 3 groups: Pre-App cohort (November 2017, before the launch of the app); App nonused, cohort (after November 2017 but not using the app); and App used cohort (after November 2017 and using the app). Univariate and multivariate analyses were performed to identify the factors related to MDT adherence. Compliance with specific adjuvant treatments, including chemotherapy, radiotherapy, endocrine therapy, and targeted therapy, was also evaluated.

RESULTS

A total of 4475 patients were included, with Pre-App, App nonused, and App used cohorts comprising 2966 (66.28%), 861 (19.24%), and 648 (14.48%) patients, respectively. Overall, 15.53% (695/4475) patients did not receive MDT recommendations; the noncompliance rate ranged from 27.4% (75/273) in 2013 to 8.8% (44/500) in 2019. Multivariate analysis demonstrated that app use was independently associated with adherence to adjuvant treatment. Compared with the patients in the Pre-App cohort, patients in the App used cohort were less likely to deviate from MDT recommendations (odds ratio [OR] 0.61, 95% CI 0.43-0.87; P=.007); no significant difference was found in the App nonused cohort (P=.77). Moreover, app use decreased the noncompliance rate for adjuvant chemotherapy (OR 0.41, 95% CI 0.27-0.65; P<.001) and radiotherapy (OR 0.49, 95% CI 0.25-0.96; P=.04), but not for anti-HER2 therapy (P=.76) or endocrine therapy (P=.39).

CONCLUSIONS

This smartphone-based app can increase MDT adherence in patients undergoing adjuvant therapy; this was more obvious for adjuvant chemotherapy and radiotherapy.

Systematic review of real-world studies evaluating the impact of medication non-adherence to endocrine therapies on hard clinical endpoints in patients with non-metastatic breast cancer

Breast cancer, one of the most common malignancies, is associated with significant economic and health burden both at the patient and societal level. Although medication non-adherence to endocrine breast cancer therapies is common, so far only limited systematic evidence has been available on its quantitative consequences, as previous systematic reviews focused mainly on factors contributing to medication non-adherence. The objective of this review was to explore the implications of medication non-adherence to endocrine therapies on hard clinical outcomes in breast cancer based on real-world studies. A systematic literature review was conducted on PubMed; empirical evidence on hard clinical endpoints (i.e., survival, disease-free survival, metastasis and recurrence) were extracted from uni- or multivariate statistical analyses from retrospective or prospective cohort studies. Of the 2,360 identified records, 12 studies met the inclusion criteria. Two studies identified significant positive association between medication non-adherence and the risk of distant metastasis, three articles between medication non-adherence and the recurrence of breast cancer, two studies between medication non-adherence- and non-persistence and of worse disease-free survival and eight articles between medication non-adherence and mortality. There was only one study where the positive association between medication adherence and survival did not apply to all subgroups. The strong evidence on the negative health consequences of non-adherence to breast cancer treatments indicates the need for the regular monitoring of medication adherence. Furthermore, explicit inclusion of adherence enhancing interventions into health policy agenda would be warranted to improve medication adherence also at a system level.

A Cross-Sectional Survey on Medication Management Practices for Noncommunicable Diseases in Europe During the Second Wave of the COVID-19 Pandemic

Maintaining healthcare for noncommunicable diseases (NCDs) is particularly important during the COVID-19 pandemic; however, diversion of resources to acute care, and physical distancing restrictions markedly affected management of NCDs. We aimed to assess the medication management practices in place for NCDs during the second wave of the COVID-19 pandemic across European countries. In December 2020, the European Network to Advance Best practices & technoLogy on medication adherencE (ENABLE) conducted a cross-sectional, web-based survey in 38 European and one non-European countries. Besides descriptive statistics of responses, nonparametric tests and generalized linear models were used to evaluate the impact on available NCD services of the number of COVID-19 cases and deaths per 100,000 inhabitants, and gross domestic product (GDP) per capita. Fifty-three collaborators from 39 countries completed the survey. In 35 (90%) countries face-to-face primary-care, and out-patient consultations were reduced during the COVID-19 pandemic. The mean ± SD number of available forms of teleconsultation services in the public healthcare system was 3 ± 1.3. Electronic prescriptions were available in 36 (92%) countries. Online ordering and home delivery of prescription medication (avoiding pharmacy visits) were available in 18 (46%) and 26 (67%) countries, respectively. In 20 (51%) countries our respondents were unaware of any national guidelines regarding maintaining medication availability for NCDs, nor advice for patients on how to ensure access to medication and adherence during the pandemic. Our results point to an urgent need for a paradigm shift in NCD-related healthcare services to assure the maintenance of chronic pharmacological treatments during COVID-19 outbreaks, as well as possible future disasters.

Adherence to treatment with oral antineoplastic therapy in outpatients

BACKGROUND

Multiple factors have defined the success of treatment with oral antineoplastic, especially adherence to the therapeutic regimen. The aim of this study was to describe the profile of individuals in treatment with oral antineoplastic according to the sociodemographic and clinical epidemiology factors as well as to estimate the association with those to Non-adherence to the treatment with oral antineoplastic.

METHODS

A cross-sectional observational study was performed in the chemotherapy outpatient's department from December 2015 to March 2016 at a teaching hospital. The outcome Non-adherence was evaluated according to Morisky Green test. The variables which have reached statistical significance in the bivariate analysis were tested in the multivariate model to evaluate if they remained associated to "Non-adherence" according to the Poisson logistic regression and corrected by robust variance.

RESULTS

In total, 233 patients were analyzed and 60.9% were found in Non-adherence to the treatment with oral antineoplastic according Morisky Green test (MMAS8), in which forgetfulness were often and had driven to non-adherence outcome. Multivariate analysis found three final predictors for Non-adherence which were own income, carer, unease and had needed urgency services in the last year.

CONCLUSION

This study reveals several factors associated with nonadherence. Those outcomes show that the patient's journey during antineoplastic treatment must be discussed and addressed in a broad way together with measures in public health policies.

Adequacy of early-stage breast cancer systemic adjuvant treatment to Saint Gallen-2013 statement: the MCC-Spain study

The St Gallen Conference endorsed in 2013 a series of recommendations on early breast cancer treatment. The main purpose of this article is to ascertain the clinical factors associated with St Gallen-2013 recommendations accomplishment. A cohort of 1152 breast cancer cases diagnosed with pathological stage < 3 in Spain between 2008 and 2013 was begun and then followed-up until 2017/2018. Data on patient and tumour characteristics were obtained from medical records, as well as their first line treatment. First line treatments were classified in three categories, according on whether they included the main St Gallen-2013 recommendations, more than those recommended or less than those recommended. Multinomial logistic regression models were carried out to identify factors associated with this classification and Weibull regression models were used to find out the relationship between this classification and survival. About half of the patients were treated according to St Gallen recommendations; 21% were treated over what was recommended and 33% received less treatment than recommended. Factors associated with treatment over the recommendations were stage II (relative risk ratio [RRR] = 4.2, 2.9-5.9), cancer positive to either progesterone (RRR = 8.1, 4.4-14.9) or oestrogen receptors (RRR = 5.7, 3.0-11.0). Instead, factors associated with lower probability of treatment over the recommendations were age (RRR = 0.7 each 10 years, 0.6-0.8), poor differentiation (RRR = 0.09, 0.04-0.19), HER2 positive (RRR = 0.46, 0.26-0.81) and triple negative cancer (RRR = 0.03, 0.01-0.11). Patients treated less than what was recommended in St Gallen had cancers in stage 0 (RRR = 21.6, 7.2-64.5), poorly differentiated (RRR = 1.9, 1.2-2.9), HER2 positive (RRR = 3.4, 2.4-4.9) and luminal B-like subtype (RRR = 3.6, 2.6-5.1). Women over 65 years old had a higher probability of being treated less than what was recommended if they had luminal B-like, HER2 or triple negative cancer. Treatment over St Gallen was associated with younger women and less severe cancers, while treatment under St Gallen was associated with older women, more severe cancers and cancers expressing HER2 receptors.

Early Discontinuation of Endocrine Therapy and Recurrence of Breast Cancer among Premenopausal Women

PURPOSE

Premenopausal women diagnosed with estrogen receptor (ER)-positive breast cancer are prescribed 5-10 years of endocrine therapy to prevent or delay recurrence. In this study, we evaluated the association between early discontinuation of endocrine therapy and breast cancer recurrence in a cohort of premenopausal women.

EXPERIMENTAL DESIGN

We identified 4,503 patients with premenopausal ER-positive breast cancer who initiated adjuvant endocrine therapy and were registered in the Danish Breast Cancer Group clinical database (2002-2011). Women were excluded if they had a recurrence or were lost to follow-up less than 1.5 years after breast cancer surgery. Endocrine therapy was considered complete if the patient received at least 4.5 years of treatment or discontinued medication less than 6 months before recurrence. Exposure status was updated annually and modeled as a time-dependent variable. We accounted for baseline and time-varying confounders via time-varying weights, which we calculated from multivariable logistic regression models, and included in regression models to estimate HRs and 95% confidence intervals (CIs) associating early discontinuation with recurrence.

RESULTS

Over the study follow-up, 1,001 (22%) women discontinued endocrine therapy. We observed 202 (20%) recurrences among those who discontinued endocrine therapy, and 388 (11%) among those who completed the recommended treatment. The multivariable-adjusted estimated rate of recurrence was higher in women who discontinued endocrine therapy relative to those who completed their treatment (hazard ratio, 1.67; 95% CI, 1.25-2.14).

CONCLUSIONS

These results highlight the importance of clinical follow-up and behavioral interventions that support persistence of adjuvant endocrine therapy to prevent breast cancer recurrence.

Impact of non-adherence to radiotherapy on 1-year survival in cancer patients in Catalonia, Spain

BACKGROUND

This study aims to assess the effects of non-adherence to external beam radiation therapy in cancer patients receiving treatment with a curative.

METHODS

This retrospective cohort study collected health records data for all cancer patients treated with external beam radiotherapy with curative intent in 2016 in Catalonia, Spain. Adherence was defined as having received at least 90% of the total dose prescribed. A logistic regression model was used to assess factors related to non-adherence, and its association with one-year survival was evaluated using Cox regression.

RESULTS

The final sample included 8721 patients (mean age 63.6 years): breast cancer was the most common tumour site (38.1%), followed by prostate and colon/rectum. Treatment interruptions prolonged the total duration of therapy in 70.7% of the patients, and 1.0% were non-adherent. Non-adherence was associated with advanced age, female gender, and some localization of primary tumour (head and neck, urinary bladder, and haematological cancers). The risk of death in non-adherent patients was higher than in adherent patients (hazard ratio [HR] 1.63, 95% confidence interval 0.97-2.74), after adjusting for the potential confounding effect of age, gender, tumour site and comorbidity.

CONCLUSION

Non-adherence to radiotherapy, as measured by the received dose, is very low in our setting, and it may have an impact on one-year survival.

Endocrine treatment and incidence of relapse in women with oestrogen receptor-positive breast cancer in Europe: a population-based study

PURPOSE

Endocrine therapy (ET) is the mainstream adjuvant treatment for ER-positive breast cancer (BC). We analysed 9293 ER-positive BC patients diagnosed in nine European countries in 2009-2013 to investigate how comorbidities at diagnosis, age, stage and subtype affected ET use over time, and relapse.

METHODS

Adjusted odds ratios (ORs) and 95% confidence intervals (95%CIs) of receiving ET were estimated according to Charlson comorbidity, age, stage and subtype using logistic regression. The 2-year cumulative incidence and adjusted sub-hazard ratios (SHRs) of relapse were estimated using competing risk analysis, with all-cause death as the competing event. The z-test was used to assess differences in the proportion of patients receiving ET in 1996-1998 and 2009-2013.

RESULTS

Ninety percent of the patients started adjuvant ET, range 96% (Belgium, Estonia, Slovenia, Spain)-75% (Switzerland). ORs of starting ET were lower for women aged > 75 years, with severe comorbidities, or luminal B HER2-positive cancer. The factors independently increasing the risk of relapse were: not receiving ET (SHR 2.26, 95%CI 1.02-5.03); severe comorbidity (SHR 1.94, 95%CI 1.06-3.55); luminal B, either HER2 negative (SHR 3.06, 95%CI 1.61-5.79) or positive (SHR 3.10, 95%CI 1.36-7.07); stage II (SHR 3.20, 95%CI 1.56-6.57) or stage III (SHR 7.41, 95%CI 3.48-15.73). ET use increased significantly but differently across countries from 51-85% in 1996-1998 to 86-96% in 2009-2013.

CONCLUSIONS

ER-positive BC patients in Europe are increasingly prescribed ET but between-country disparities persist. Older women and women with severe comorbidity less frequently receive ET. ET omission and severe comorbidity independently predict early disease relapse.

Factors influencing adherence to adjuvant endocrine therapy in breast cancer-treated women: using real-world data to inform a switch from acute to chronic disease management

PURPOSE

Adjuvant endocrine therapy (AET) for ≥ 5 years is generally recommended for women with hormone receptor-positive breast cancer to reduce cancer recurrence/mortality; however, adherence can be suboptimal. We tested determinants of AET adherence using patient characteristics, treatment pathways, AET initiation timing, and multiple healthcare facility use. An underlying objective was to explore how oncological pathways mirror chronic disease management to monitor adherence and target improvement interventions using administrative datasets.

METHODS

Using patient-linked administrative health data from the Italian Lombardy Region, we identified 33.291 surviving patients starting AET in 2010-2016, with two (22.939 patients) or five years (8400 patients) follow-up, using a ≥ 80% prescription refill approach to measure adherence and logistic regression to test determinants of adherence.

RESULTS

AET crude adherence falls significantly during follow-up, from 94% at 1 Year to 58% at 5 Years. At 5 Years, patients who were older (>70), prescribed tamoxifen-only (OR 0.69; 95% CI 0.57-0.83; p = 0.0001) vs. aromatase inhibitors-only or therapy switches, treated for depression (OR 0.68; 95% CI 0.60-0.78; p < 0.0001), with surgery performed in high-volume hospitals (OR 0.85; 95% CI 0.75-0.97; p = 0.0116) showed lower adherence. Loyalty, or continued care in the surgical hospital (OR 1.73; 95% CI 1.51-2.00; p < 0.0001), undergoing chemotherapy before AET (OR 2.65; 95% CI 2.02-3.48; p < 0.0001), and earlier AET initiation, positively influenced adherence.

CONCLUSIONS

Chronic disease monitoring using administrative data can help oncologists focus efforts to ensure AET adherence. Results suggest addressing mental health, age, disease severity patient perceptions, timely AET initiation and therapy switches, and encouraging continued follow-up in the same hospital or better care coordination with outside follow-up specialists.