Incidence and Predictors of Diabetes Mellitus after a Diagnosis of Early-Stage Breast Cancer in the Elderly Using Real-World Data

Disparities in PI3K/mTOR inhibitor use, toxicities, and outcomes among patients with metastatic breast cancer

PURPOSE

Novel agents such as PI3K and mTOR inhibitors (PI3K/mTORi) have expanded treatment options in metastatic breast cancer (MBC). Nevertheless, mortality rates remain disproportionately high for Black patients and patients with lower socioeconomic status. Furthermore, clinical trials for these novel agents lacked diversity, so their toxicity profile in minority populations is uncertain.

METHODS

We conducted a retrospective analysis of EHR-derived data from the Flatiron Health Database for patients with HR+, HER2- MBC. Multivariable logistic regression was used to evaluate factors associated with PI3K/mTORi use and toxicity outcomes.

RESULTS

A total of 9169 patients with MBC were included in our analysis, of which 1780 (19.4%) received a PI3K/mTORi. We estimated the conditional total effect of insurance through Medicaid, and found lower odds of use of PI3K/mTORi among patients on Medicaid compared to those with commercial insurance (OR 0.73, 95% CI 0.54-0.99, p = 0.049). Odds of PI3K/mTORi use were higher for patients treated at an academic center (OR 1.28, CI 1.06-1.55, p = 0.01). Modeled as a controlled direct effect, Black/African American (Black/AA) race had no impact on odds of PI3K/mTOR use. Black/AA patients had twice the odds of developing hyperglycemia on PI3K/mTORi compared to White patients (OR 2.02, CI 1.24-3.39, p < 0.01).

CONCLUSION

This analysis of real-world data suggests that the use of PI3K/mTORi is influenced by socioeconomic factors. We also found racial disparities in toxicity outcomes, with Black/AA patients having twice the risk of hyperglycemia. Our findings call for greater efforts to ensure access to novel treatments and improve their tolerability in diverse populations.

Incident diabetes among older Asian, Native Hawaiian, and Pacific Islander women with breast cancer

BACKGROUND

The risk of diabetes among Asian, Native Hawaiian, and Pacific Islander (ANHPI) women after breast cancer is unclear. This study estimated the risk of incident type II diabetes in older ANHPI and older non-Hispanic White (NHW) women with breast cancer from the US National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Medicare linked claims.

METHODS

A matched cohort of 7122 older ANHPI and 21 365 older NHW women with breast cancer were identified from SEER-Medicare between 2000 and 2017. To assess the risk of incident type II diabetes after breast cancer, hazard ratios (HRs) and 95% confidence intervals (95% CI) were estimated using the Cox proportional-hazards regression model.

RESULTS

During the mean 8 years of follow-up, 9.3% of older women with breast cancer developed incident type II diabetes. In comparison with older NHW women, older ANHPI women without a known history of diabetes had an elevated risk of diabetes after breast cancer, with strong associations observed for Pacific Islander (HR = 3.09, 95% CI = 1.43 to 6.67), Vietnamese (HR = 2.12, 95% CI = 1.33 to 2.36), and Filipino (HR = 2.02, 95% CI = 1.57 to 2.59) women with breast cancer, adjusting for potential confounders. Among ANHPI women with breast cancer, more baseline comorbidities and obesity were risk factors for developing incident type II diabetes.

CONCLUSION

ANHPI women diagnosed with breast cancer had an elevated risk of type II diabetes compared with older NHW women with breast cancer. Routine monitoring and management of diabetes are warranted in older ANHPI women with breast cancer.

Breast cancer and incidence of type 2 diabetes mellitus: a systematic review and meta-analysis

PURPOSE

Breast cancer and its treatments may increase the risk of type 2 diabetes (T2D). We conducted a systematic review and meta-analysis to investigate the association between breast cancer and the incidence of T2D overall, and according to breast cancer treatments.

METHODS

We searched PubMed, Embase and references of relevant papers for studies on breast cancer, breast cancer treatment, and subsequent T2D risk. Using random-effects models, we calculated effect estimates and associated 95% confidence intervals of the association between breast cancer, adjuvant breast cancer treatments (i.e., endocrine therapy (tamoxifen, aromatase inhibitors, and combined) and chemotherapy), and subsequent T2D. We used funnel plots to assess publication bias.

RESULTS

Among 15 eligible studies, 10 reported on T2D risk after breast cancer, chemotherapy, or endocrine therapy; five studies investigated more than one association. Compared with patients without breast cancer, those with breast cancer and those who received any endocrine therapy had elevated risk of incident T2D (EE = 1.23, 95% CI = 1.13-1.33 and EE = 1.23, 95% CI = 1.16-1.32, respectively). Among breast cancer patients only, the risk of T2D was higher for those who received tamoxifen compared with those who did not receive tamoxifen (EE = 1.28, 95% CI = 1.18-1.38). Due to few studies, analyses investigating T2D risk after treatment with aromatase inhibitors or chemotherapy were inconclusive.

CONCLUSION

Our findings suggest an elevated risk of T2D in breast cancer survivors, particularly after tamoxifen therapy. Further research is needed to determine the impact of aromatase inhibitors, and chemotherapy on the incidence of T2D after breast cancer.

Non cancer causes of death after gallbladder cancer diagnosis: a population-based analysis

Mortality from non cancer causes in patients with gallbladder cancer (GBC) still unclear. This study evaluated the causes and risk factors of non cancer death during different follow-up periods after GBC diagnosis. Non cancer causes of death for GBC patients diagnosed between 2000 and 2017 in Surveillance, Epidemiology and End Results database were analyzed and standardized mortality rates (SMR) for each non cancer death were calculated. Predictors for non cancer death were identified through multivariate competing risk analysis. A total 11,927 GBC patients were identified for further analysis, 9393 died during follow up. The largest proportion of non cancer deaths occurred > 3 years after diagnosis (39.4%). Most common non cancer cause were cardiovascular disease (43.3%), followed by other cause of death (34.4%) and infectious diseases (8.6%). Compared with US general population, GBC patients has higher risk of death from disease of heart (SMR, 1.58; 95%CI, 1.41-1.75), septicemia (SMR,3.21; 95%CI, 2.27-4.40), diabetes mellitus (SMR,1.97; 95%CI, 1.43-2.63), alone with other causes. Non cancer causes accounted for a significant proportion of deaths during the follow-up period after GBC diagnosis. The risk of non cancer death is higher in GBC patients than in the general population. Our study provides comprehensive assessment of death from non cancer cause in GBC patients, which has important implications for health management in GBC patients.

Systemic Lupus Erythematosus and Mortality in Elderly Patients With Early Breast Cancer

OBJECTIVE

Patients with cancer and systemic lupus erythematosus (SLE) may have worse outcomes than those without SLE, given their comorbidities. We examined survival in elderly women with breast cancer (BC) and SLE and hypothesized that survival would be decreased compared with women with BC but without SLE.

METHODS

We identified patients with BC and SLE and patients with BC without SLE in the Texas Cancer Registry and Surveillance, Epidemiology, and End Results, linked to Medicare claims. Overall survival (OS) was estimated after matching (age and cancer stage) and in multivariable Cox proportional hazards models adjusting for other cancer characteristics, treatment, and comorbidities. Two additional cohorts of women without cancer with and without SLE were also studied.

RESULTS

We identified 494 BC SLE cases and 145,517 BC non-SLE cases, of whom we matched 9,708. Women with SLE were less likely to receive radiation, breast conserving surgery, or endocrine therapy. The 8-year OS estimate for women with early BC (stages 0-II) with and without SLE was 52% (95% confidence interval [95% CI] 45%-59%) and 74% (95% CI 73%-75%), respectively. In the Cox multivariable model, BC and SLE had increased risk of death (hazard ratio [HR] 1.65, 95% CI 1.38-1.98). Women with BC and SLE also had increased risk of death compared with women with SLE but without cancer (HR 1.42, 95% CI 1.05-1.92) after adjusting for SLE severity. Women with SLE and BC received less glucocorticoids, antimalarials, and immunosuppressants after cancer diagnosis than those without cancer.

CONCLUSION

Systemic lupus is a risk factor for increased mortality in women with early BC.

Higher Incidence of Diabetes in Cancer Patients Compared to Cancer-Free Population Controls: A Systematic Review and Meta-Analysis

Background: Diabetes increases the risk of certain types of cancer. However, the literature regarding the incidence of diabetes after cancer diagnosis is inconsistent. We aimed to assess whether there was a higher incidence of diabetes among cancer patients by performing a systematic review and meta-analysis of results from cohort studies. Methods: A systematic electronic literature search was carried out from cohort studies regarding the incidence of diabetes in cancer patients, using the databases PubMed (MEDLINE), Embase, Web of Science, and the Cochrane Library. Random-effects meta-analyses were conducted to pool the estimates. Results: A total of 34 articles involving 360,971 cancer patients and 1,819,451 cancer-free controls were included in the meta-analysis. An increased pooled relative risk (RR) of 1.42 (95% confidence interval (CI): 1.30−1.54, I2 = 95, τ2 = 0.0551, p < 0.01) for diabetes in cancer patients was found compared with the cancer-free population. The highest relative risk was observed in the first year after cancer diagnosis (RR = 2.06; 95% CI 1.63−2.60). Conclusions: New-onset diabetes is positively associated with cancer, but this association varies according to cancer type. More prospective studies with large sample sizes and longer follow-up times are advocated to further examine the association and the underlying mechanisms.

Relationships between peripheral reactive hyperemia index with coronary plaque burden and prognosis in patients with unstable angina pectoris complicated with type 2 diabetes mellitus

Background

Coronary plaque burden (CPB) is an important prognostic factor in patients with unstable angina pectoris (UAP). Our current study aims to investigate the relationships between peripheral reactive hyperemia index (RHI) with CPB and prognosis in patients with UAP complicated with type 2 diabetes mellitus (T2DM).

Methods

The clinical data of 187 UAP-T2DM patients who were treated in our center from June 2017 to January 2019 were retrospectively collected. RHI, CPB, and other clinical features were measured. The patients were followed up for 18 months and then divided into an adverse cardiovascular event (ACE) group (n=71, with ACEs) and a control group (n=116, without ACEs). The differences in RHI, CPB, and other clinical features between these two groups were compared, and the potential correlation between RHI and CPB was analyzed.

Results

Compared with the control group, the ACE group had significantly lower RHI (1.21±0.32 vs. 1.59±0.35, P=0.000) and left ventricular ejection fraction (LVEF) (42.92%±7.78% vs. 48.90%±6.76%, P=0.000) and a significantly higher left ventricular myocardial mass index (2.67±0.87 vs. 2.27±0.49 mg/g, P=0.000), carotid intima-media thickness (1.65±0.34 vs. 1.51±0.32 mm, P=0.000), number of coronary plaques (3.98±0.53 vs. 3.32±0.38, P=0.000), non-calcified plaque volume (32.89±12.56 vs. 22.58±9.97 mm³, P=0.000), calcified plaque volume (4.89±1.29 vs. 3.88±1.05 mm³, P=0.000), non-calcified plaque burden (5.70%±1.60% vs. 3.18%±1.08%, P=0.000), and calcified plaque burden (0.90%±0.22% vs. 0.65%±0.19%, P=0.000). Pearson linear correlation analysis showed that peripheral RHI was negatively correlated with plaque number, non-calcified plaque volume, calcified plaque volume, non-calcified plaque burden, and calcified plaque burden in patients with UAP complicated with T2DM (all P<0.05).

Conclusions

Decreased peripheral RHI is associated with ACEs and CPB in patients with UAP complicated with T2DM.