ASPO Abstracts
The impact of diabetes on adherence to breast cancer screening guidelines and breast cancer detection
Category: Early Detection & Risk Prediction, Survivorship & Health Outcomes/Comparative Effectiveness Research
Conference Year: 2018
Abstract Body:
Background: Over 250,000 women were diagnosed with breast cancer (BC) in 2017, and 20% had Type II diabetes mellitus (DM). Patient with both conditions have poorer outcomes with a 52% increased mortality risk. There is limited information about whether and why outcomes may be worse in women with both BC and DM versus only BC. Early detection of BC through screening reduces morbidity and mortality, but the success of screening and early detection depends on determining whether or not women are screened at regular intervals. Objective: Assess whether BC patients with DM were less adherent to screening recommendations prior to BC diagnosis, leading to a higher probability of symptom- detected, later-stage tumors than women without DM. Methods: Retrospective cohort study of 2,054 women 52+ years diagnosed with stage I-IIIA BC during 1999-2014 and receiving care within a large health plan in Washington State with linkage to the SEER tumor registry. Women diagnosed with DM, as determined through the electronic health records on diagnoses, laboratory values, and pharmacy records, were compared to women without DM for: screening mammography or MRI in the 2 years prior to BC diagnosis, symptom-detected BC, and stage of BC. Modified Poisson regression with robust standard errors adjusting for age, year of BC diagnosis, race, body mass index, and comorbidity index was used to estimate relative risks (RR) and 95% confidence intervals (CI). . Results: Approximately 13% of women in the cohort had DM. Receipt of a screening mammogram in the two years prior to BC was similar between the two groups (79% of women with DM; 77% of women without DM) for a RR =1.05 (95% CI, 0.98 — 1.13). Women with DM were less likely to be symptom- vs screen-detected for BC than women without DM (45% vs. 50%); RR=0.93; 95% CI, 0.80-1.07). Diagnosis of stage IIIA vs. stage I-II was similar between the groups (6.8% both groups; RR=1.0; 95% CI, 0.59-1.59). Conclusion: This study does not support the hypothesis that differences in BC screening rates, symptom-detected cancers, and stage at diagnosis explain poorer outcomes among women with DM. The study was conducted in one health system and warrants replication in other setting and populations.
Keywords: Breast cancer Screening Comorbidity Diabetes Survivorship