Use of health services among long-term breast cancer survivors in Spain: longitudinal study based on real-world data.

PURPOSE: This study aimed to evaluate health service utilization in Spain among long-term breast cancer survivors and to compare it with that among women with no history of breast cancer. METHODS: Study based on the SURBCAN cohort includes a sample of long-term breast cancer survivors and a sample of women without breast cancer from 5 Spanish regions. Healthcare utilization was assessed through primary care, hospital visits, and tests during the follow-up period (2012 to 2016) by using electronic health records. Annual contact rates to healthcare services were calculated, and crude and multivariate count models were fitted to estimate the adjusted relative risk of healthcare services use. RESULTS: Data were obtained from 19,328 women, including 6512 long-term breast cancer survivors. Healthcare use was higher among breast cancer survivors (20.9 vs 16.6; p < 0.0001) and decreased from >10 years of survival. Breast cancer survivors who underwent a mastectomy were more likely to have a primary care visit (RR = 3.10 95% CI 3.08-3.11). Five to ten years survivors were more likely to have hospital inpatient visits and imaging test compared to women without breast cancer (RRa = 1.35 95% CI 1.30-1.39 and RRa = 1.27 95% CI 1.25-1.29 respectively). CONCLUSION: This study shows higher use of health services in long-term breast cancer survivors than in women without breast cancer regardless of survival time. IMPLICATIONS FOR CANCER SURVIVORS: These results help to estimate the health resources needed for the growing group of breast cancer survivors and to identify risk factors that drive higher use of health services.

Multimorbidity clusters among long-term breast cancer survivors in Spain: Results of the SURBCAN study.

The disease management of long-term breast cancer survivors (BCS) is hampered by the scarce knowledge of multimorbidity patterns. The aim of our study was to identify multimorbidity clusters among long-term BCS and assess their impact on mortality and health services use. We conducted a retrospective study using electronic health records of 6512 BCS from Spain surviving at least 5 years. Hierarchical cluster analysis was used to identify groups of similar patients based on their chronic diagnoses, which were assessed using the Clinical Classifications Software. As a result, multimorbidity clusters were obtained, clinically defined and named according to the comorbidities with higher observed/expected prevalence ratios. Multivariable Cox and negative binomial regression models were fitted to estimate overall mortality risk and probability of contacting health services according to the clusters identified. 83.7% of BCS presented multimorbidity, essential hypertension (34.5%) and obesity and other metabolic disorders (27.4%) being the most prevalent chronic diseases at the beginning of follow-up. Five multimorbidity clusters were identified: C1-unspecific (29.9%), C2-metabolic and neurodegenerative (28.3%), C3-anxiety and fractures (9.7%), C4-musculoskeletal and cardiovascular (9.6%) and C5-thyroid disorders (5.3%). All clusters except C5-thyroid disorders were associated with higher mortality compared to BCS without comorbidities. The risk of mortality in C4 was increased by 64% (adjusted hazard ratio 1.64, 95% confidence interval 1.52-2.07). Stratified analysis showed an increased risk of death among BCS with 5 to 10 years of survival in all clusters. These results help to identify subgroups of long-term BCS with specific needs and mortality risks and to guide BCS clinical practice regarding multimorbidity.

Use of real-world data to study health services utilisation and comorbidities in long-term breast cancer survivors (the SURBCAN study): study protocol for a longitudinal population-based cohort study.

INTRODUCTION: Breast cancer has become a chronic disease due to survival improvement and the need to monitor the side effects of treatment and the disease itself. The aim of the SURBCAN study is to describe comorbidity, healthcare services use and adherence to preventive recommendations in long-term breast cancer survivors and to compare them with those in women without this diagnosis in order to improve and adapt the care response to this group of survivors. METHODS AND ANALYSIS: Population-based retrospective cohort study using real-world data from cancer registries and linked electronic medical records in five Spanish regions. Long-term breast cancer survivors diagnosed between 2000 and 2006 will be identified and matched by age and administrative health area with women without this diagnosis. Sociodemographic and clinical variables including comorbidities and variables on the use of health services between 2012 and 2016 will be obtained from databases in primary and hospital care. Health services use will be assessed through the annual number of visits to primary care professionals and to specialists and through annual imaging and laboratory tests. Factors associated with healthcare utilisation and comorbidities will be analysed using multilevel logistic regression models. Recruitment started in December 2018. ETHICS AND DISSEMINATION: This study was approved by the Ethics Committee of Parc de Salut Mar. The results of the study will be published in a peer-reviewed journal and will be presented at national and international scientific conferences and at patient associations. TRIAL REGISTRATION NUMBER: This protocol is registered in Clinical Trials.gov (identifier: NCT03846999).