P1-08-18: Aspirin Exposure and Nodal Status at Diagnosis in Women with Stage I-III Breast Cancer

Background: The recent Nurses’ Health Study reported an association between aspirin use and a reduction in breast cancer (BC) recurrence and BC-specific mortality. It has been suggested based on preclinical data that these effects may be due to the inhibition of tumor invasion and metastasis by aspirin. To test this hypothesis we examined the association between aspirin exposure prior to BC diagnosis and nodal involvement at diagnosis.

Methods: A retrospective analysis was conducted using linked pharmacy claims and cancer registry data from the National Cancer Registry Ireland. Women with an incident diagnosis of stage I-III BC between 2001–2006 and no prior invasive cancer were included. Women with a prescription for aspirin at any time in the year prior to diagnosis were defined as exposed. Multivariate logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for (a) N0 disease; (b) N1 disease (c) N1/2/3 disease at diagnosis in aspirin exposed (overall exposure & exposure quartiles by duration of use) versus unexposed women. All analyses were adjusted for age, tumor size/grade, ER, PR and HER2 receptor status. Analyses were repeated including women with stage IV BC at diagnosis. Survival analyses are ongoing.

Results: 4212 women with stage I-III BC at diagnosis were identified. 1086 (25.8%) had a supply of aspirin available to them in the year prior to diagnosis (median dose 75mg, interquartile range 75mg, 75mg). Women taking aspirin were older than those who did not (74.3 yrs/64.4 yrs p<0.05). There was no difference in tumor sizes, grade, ER, PR or HER2 receptor status between exposed and unexposed women. In the multivariate logistic regression analysis aspirin exposure was associated with significantly increased odds of an N0 tumor (Table 1; OR 1.27 95%CI 1.09, 1.48) and significantly decreased odds of an N1 or N1/2/3 tumor. Additionally, women taking aspirin for >95% of the year prior to diagnosis had the highest odds of an N0 tumor (Table1; OR 1.50 95%CI 1.14, 1.97). There was no difference in the odds of an N0 tumor for women taking aspirin for <40% of the prior year (OR 1.01 95%CI 0.78, 1.31). Inclusion of stage IV BC (n=789) in the analysis did not significantly alter these results.

Trends in COPD mortality and in-patient admissions in men & women: evidence of convergence

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality. Although more prevalent in men, it is anticipated that, due to the convergence in smoking rates, the prevalence rate in women will surpass that of men. There were 14,519 deaths attributable to COPD in the period 2000-2009. Although deaths decreased for both sexes, reduction in deaths was significantly higher among men (test for trend, p<0.01 for men vs. p=0.06 for women). Smoking rates decreased for both sexes from 1980-2009 with the percentage reduction in smoking significantly greater in men (11.5% vs. 7.0%, p<0.001). There has been a convergence in COPD deaths and COPD hospital in-patient discharges for men and women that mirrors the trend in the convergence of male and female smoking rates. This study provides evidence of the need for effective smoking cessation programmes that are targeted at women as well as men.

Irish Medicines Board safety warnings: do they affect prescribing rates in primary care?

PURPOSE

To examine the impact of safety warnings issued between 2005 and 2007 by the Irish Medicines Board (IMB) on the rate of prescribing of clopidogrel, co-amoxiclav, celecoxib and haloperidol by primary care physicians in the General Medical Services (GMS) scheme across Ireland.

METHODS

This study was performed using the Irish Health Service Executive-Primary Care Reimbursement Services national prescribing database. Rate of prescribing per 1000 GMS population was calculated for each of the 12 months before and after the IMB warnings were issued to physicians. A segmented regression analysis was used to examine the change in level and trend in prescribing rates before and after the IMB warnings. Regression coefficients are presented with SEs. Significance at p < 0.05 was assumed. SPSS 16 and SAS were used for statistical analysis.

RESULTS

Prescribing of clopidogrel continued to rise in both genders following the warning. This increase was slightly higher in male patients. The prescribing of co-amoxiclav showed seasonal variation with significant autocorrelation. The rate of prescribing of celecoxib declined approximately 4  months prior to the IMB warning. A significant decrease in the level and trend of the rate of prescribing of celecoxib was observed with evident discontinuity. The IMB warning had no significant effect on the level of trend in the prescribing of haloperidol, suggesting no discontinuity.

CONCLUSIONS

Results indicate that the IMB safety warnings had inconsistent effects on the rate of prescribing of drugs considered.

Increasing evidence-based treatments to reduce coronary heart disease mortality in Sweden: quantifying the potential gains

OBJECTIVES

Between 1986 and 2002, coronary heart disease (CHD) mortality in Sweden fell by more than 50%. Approximately one-third (4800 fewer deaths) of this decline in age-adjusted CHD mortality could be attributed to treatments in patients with CHD and primary prevention medications. High treatment levels were achieved in some cases, but in others, only 50-80% of eligible patients received appropriate therapy. We therefore examined to what extent increasing the use of specific treatments in eligible patients might have reduced CHD mortality rates in Sweden.

DESIGN AND METHODS

We used the previously validated IMPACT CHD model to combine data on CHD patient numbers, medical and surgical uptake levels and treatment effectiveness. We estimated the number of deaths prevented or postponed for 2002 (baseline scenario) and for an alternative scenario (if at least 60% of eligible patients were treated).

RESULTS

If treatments were increased to consistently cover at least 60% of eligible patients, approximately 8900 deaths could have been postponed or prevented, representing a potential gain of approximately 4100 fewer deaths than actually occurred in 2002. Approximately 45% of the 4100 gain would have come from primary prevention with statins, 23% from acute coronary syndrome treatments, 15% from secondary prevention therapies and 15% from treatments for heart failure.

CONCLUSION

Increasing the proportion of eligible patients with CHD who receive evidence-based treatment could have resulted in approximately 4100 fewer deaths in 2002, almost doubling the actual mortality reduction. These findings further emphasize the importance of aggressively identifying and treating patients with CHD and high-risk individuals.

HeartBeat--improving heart attack care

We aimed to save lives by assuring best practice in ST elevation myocardial infarction (STEMI) through initiating the Institute for Healthcare Improvement (IHI) methodology nationally. Following collection of a minimum dataset, annual change in indicators in the five initiating hospitals for the period Oct 2006 - Sept 2009 was assessed by analysing the percentage of patients receiving the eight components of evidenced based care on admission and discharge and in-hospital mortality rate. For 635 patients, performance on seven of the eight indicators of care exceeded 90% annually. Timely reperfusion therapy (thrombolysis, primary percutaneous coronary intervention (PPCI)) improved non-significantly from 68.2% (107 patients) in year 1 to 77.1% (118 patients) in year 3. In-hospital mortality declined significantly from 12.4% (24 deaths) in year 1 to 5% (9 deaths) in year 3. Evidence based STEMI care is followed to a high degree but timely reperfusion and PPCI provision remain a challenge nationally.

The increased mortality associated with a weekend emergency admission is due to increased illness severity and altered case-mix

BACKGROUND

A weekend emergency medical admission has been associated with a higher mortality. We have examined all weekend admissions to St James' Hospital, Dublin between 2002 and 2009.

METHODS

We divided admissions by weekday or weekend (Saturday or Sunday) presentation. We utilised a multivariate logistic model, to determine whether a weekend admission was independently predictive of 30 day outcome.

RESULTS

There were 49337 episodes recorded in 25883 patients; 30-day inhospital mortality at the weekend (9.9% vs. 9.0%) had an unadjusted Odds Ratio of 1.11 (95% CI 0.99, 1.23: p=0.057). In the full risk unlike the univariate) model, a weekend admission was not independently predictive (OR 1.05; 95% CI: 0.88, 1.24). The case-mix for a weekend admission differed; with more neurological diagnoses (22.8% vs 20.4% : p = 0.001) and less gastrointestinal disease (18.3% vs 21.1% : p = 0.001). A biochemistry only illness severity score predicted a higher mortality for weekend admissions.

CONCLUSION

Patients admitted at the weekend had an approximate 11% increased 30-day in-hospital mortality, compared with a weekday admission. However, admission at the weekend was not independently predictive in a risk model that included Illness Severity (age and biochemical markers) and co-morbidity. Sicker patients, with a worse outcome, are admitted over the weekend; these considerations should inform the allocation of healthcare resources.

Abstract P3-11-05: Association between Propanolol Use and Both Breast Cancer Incidence and Mortality

Background: The neurotransmitter epinephrine has been shown to promote breast cancer tumor cell migration, mediated through the ≥2 adrenergic pathway. In-vitro and in-vivo studies have demonstrated that the non-selective ≥1/≥2 adrenergic receptor antagonist propranolol inhibits the effects of epinephrine on breast cancer cell motility. Based on these studies we hypothesize that propranolol use prior to breast cancer diagnosis may result in a lower risk of locally advanced or metastatic disease at diagnosis and decrease the risk of breast cancer recurrence and mortality. Methods: To test these hypotheses we conducted a series of matched observational studies in a largely unscreened population, using pharmacy claims data linked to cancer registry data from the National Cancer Registry Ireland (NCRI, 2000-2007, n=5,949). Conditional logistic regression was used to estimate the odds ratio (OR) and 95% confidence intervals (CI) for stage at diagnosis. A Cox proportional hazard model was used to estimate the hazard ratio (HR) for breast cancer mortality. All analyses were repeated with atenolol, a selective ≥1 adrenergic receptor antagonist. Results: 71 patients taking propranolol in the year prior to breast cancer diagnosis were identified from the NCRI database (mean age 65; Stage-1 19.7%; Stage-2 57.8%; Stage-3 8.5%; Stage-4 8.5%; Unknown 5.6%). Patients taking propranolol in the year prior to breast cancer diagnosis were matched (1:2) using propensity scores to patients not taking a β-blocker by age, tumor grade, comorbidities, co-medications, demographics and socio-economic status. The odds of developing a T4 tumour for patients taking propranolol was OR 0.22, 95%CI 0.02, 0.98. (Atenolol: OR 1.29, 95%CI 0.83, 2.00). There was a twofold increase in the odds of developing a N0/M0 tumour (OR 2.02, 95%CI 1.03, 3.99) for patients taking propranolol in the year prior to breast cancer diagnosis compared to patients not taking a β-blocker after matching (1:2) for age, tumor size, tumor grade, and co-medications. (Atenolol OR 0.94, 95%CI 0.73, 1.19). Patients taking propranolol at the time of breast cancer diagnosis were matched to patients not taking a β-blocker (1:2) by age, tumor stage, tumor grade and comorbidities. At five years the cumulative probability of breast cancer death was 12.3% in patients taking propranolol and 33.3% in matched controls, HR 0.22, 95%CI 0.08, 0.61. (Atenolol HR 1.02, 95%CI 0.79, 1.31).

Discussion: The use of propranolol, a non-selective ≥1/≥2 adrenergic receptor antagonist, results in a statistically significant reduction in the risk of locally advanced or metastatic breast cancer. The use of propranolol was also associated with a significant reduction in breast cancer mortality. No effect was observed with the use of a selective ≥1 adrenergic receptor antagonist. This suggests that the effects of propranolol in breast cancer are mediated through the ≥2 adrenergic pathway, supporting preclinical observations. To our knowledge, this is the first epidemiological study to examine the effects of propranolol on breast cancer stage at presentation and survival. Our results provide rationale for further investigation of this agent in breast cancer patients.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-11-05.

An improved medical admissions risk system using multivariable fractional polynomial logistic regression modelling

AIM

To develop and validate an in-hospital mortality risk prediction tool for unselected acutely ill medical patients using routinely collected physiological and laboratory data.

DESIGN

Analysis of all emergency medical patients admitted to St James's Hospital (SJH), Dublin, between 1 January 2002 and 31 December 2007. Validation using a dataset of acute medical admissions from Nenagh Hospital 2000-04.

METHODS

Using routinely collected vital signs and laboratory findings, a composite 5-day in-hospital mortality risk score, designated medical admissions risk system (MARS), was developed using an iterative approach involving logistic regression and multivariable fractional polynomials. Results are presented as area under receiver operating characteristics curves (AUROC) as well as Hosmer and Lemeshow goodness-of-fit statistics.

RESULTS

A total of 10 712 and 3597 unique patients were admitted to SJH and Nenagh Hospital, respectively. The final score included nine variables [age, heart rate, mean arterial pressure, respiratory rate, temperature, urea, potassium (K), haematocrit and white cell count]. The AUROC for 5-day in-hospital mortality was 0.93 [95% confidence interval (CI) 0.92-0.94] for the SJH cohort (Hosmer and Lemeshow test, P = 0.32) and 0.92 (95% CI 0.90-0.94) for the external Nenagh hospital validation cohort (Hosmer and Lemeshow test, P = 0.28).

CONCLUSION

In-hospital mortality estimation using only routinely collected emergency department admission data is possible in unselected acute medical patients using the MARS system. Such a score applied to acute medical patients at the time of admission, could assist senior clinical decision makers in promptly and accurately focusing limited clinical resources. Further studies validating the impact of this model on clinical outcomes are warranted.

Immunosuppression and atypical infections in CML patients treated with dasatinib at 140 mg daily

BACKGROUND

The multikinase inhibitor dasatinib exerts growth-inhibitory effects in patients with imatinib-resistant chronic myeloid leukaemia (CML). In first clinical trials, side effects of dasatinib, 140 mg daily, were reported to be mild and tolerable.

PATIENTS AND METHODS

We examined the side effect profile in 16 patients with imatinib-resistant CML who received 140 mg dasatinib daily in our center.

RESULTS

Dasatinib produced substantial and sometimes severe or even life-threatening side effects with > or = 10% body weight loss (6/16 patients), pleural effusions grade II or higher (12/16) and infectious complications (12/16), including atypical infections not seen in imatinib-treated patients. One patient developed Epstein-Barr-Virus-positive mucosal leucoplakia, one died from pneumonia caused by pneumocystis carinii and three patients developed a skin-cancer. Most events were recorded within the first 2 years of therapy, only skin tumours developed after the second year. In ex vivo experiments performed in dasatinib-treated patients, transient suppression of IgE-dependent activation of blood basophils and TcR-dependent activation of T-lymphocytes was found. Moreover, in drug-binding studies, dasatinib was found to bind to several key kinase-targets of the immune system including Lyn and Btk, in mast cell, basophil, B-cell and T-cell lines.

CONCLUSION

Dasatinib acts not only anti-neoplastic in CML but may also act as an immunosuppressive agent when applied at 140 mg daily, and produces frequent pleural effusions and weight loss in advanced CML.