Causes of death in men undergoing androgen suppression therapy for newly diagnosed localized or recurrent prostate cancer

Protocol for a phase III RCT and economic analysis of two exercise delivery methods in men with PC on ADT

BACKGROUND

Androgen deprivation therapy (ADT) is commonly used to treat prostate cancer. However, side effects of ADT often lead to reduced quality of life and physical function. Existing evidence demonstrates that exercise can ameliorate multiple treatment-related side effects for men on ADT, yet adherence rates are often low. The method of exercise delivery (e.g., supervised group in-centre vs. individual home-based) may be important from clinical and economic perspectives; however, few studies have compared different delivery models. Additionally, long-term exercise adherence and an understanding of predictors of adherence are critical to achieving sustained benefits, but such data are lacking. The primary aim of this multi-centre phase III non-inferiority randomized controlled trial is to determine whether a home-based delivery model is non-inferior to a group-based delivery model in terms of benefits in fatigue and fitness in this population. Two other key aims include examining cost-effectiveness and long-term adherence.

METHODS

Men diagnosed with prostate cancer of any stage, starting or continuing on ADT for at least 6 months, fluent in English, and living close to a study centre are eligible. Participants complete five assessments over 12 months (baseline and every 3 months during the 6-month intervention and 6-month follow-up phases), including a fitness assessment and self-report questionnaires. Biological outcomes are collected at baseline, 6, and 12 months. A total of 200 participants will be randomized in a 1:1 fashion to supervised group training or home-based training supported by smartphones, health coaches, and Fitbit technology. Participants are asked to complete 4 to 5 exercise sessions per week, incorporating aerobic, resistance and flexibility training. Outcomes include fatigue, quality of life, fitness measures, body composition, biological outcomes, and program adherence. Cost information will be obtained using patient diary-based self-report and utilities via the EQ-5D.

DISCUSSION

To disseminate publicly funded exercise programs widely, clinical efficacy and cost-effectiveness have to be demonstrated. The goals of this trial are to provide these data along with an increased understanding of adherence to exercise among men with prostate cancer receiving ADT.

TRIAL REGISTRATION

The trial has been registered at clinicaltrials.gov (Registration # NCT02834416 ). Registration date was June 2, 2016.

Approach to Androgen Deprivation in the Prostate Cancer Patient with Pre-existing Cardiovascular Disease

PURPOSE OF REVIEW

Androgen deprivation therapy (ADT) is a mainstay of treatment for advanced prostate cancer. Several studies have reported an association between ADT and an increase in cardiovascular events, especially in those receiving gonadotropin-releasing hormone (GnRH) agonists compared to GnRH antagonists. We review the body of literature reporting the association of ADT and cardiovascular morbidity, and discuss the proposed mechanism of cardiovascular disease due to ADT including metabolic changes that may promote atherosclerosis and local hormonal effects that may increase plaque rupture and thrombosis.

RECENT FINDINGS

GnRH agonists appear to increase the risk of cardiovascular morbidity by 20-25% in men on these agents compared those who do not receive ADT. GnRH antagonists may appear to have halve this risk while improving PSA progression-free survival. GnRH antagonists may be superior to GnRH agonists for patients with significant cardiovascular disease, significant metastatic disease burden, or severe lower urinary tract symptoms.

A meta-analysis of cardiovascular events in intermittent androgen-deprivation therapy versus continuous androgen-deprivation therapy for prostate cancer patients

BACKGROUND

Androgen-deprivation therapy (ADT) is the standard treatment for advanced and recurrent prostate cancer but it has been shown to cause adverse effects on the cardiovascular system. Intermittent androgen deprivation has been studied as an alternative therapy. To conduct a meta-analysis comparing the incidence of cardiovascular events in patients with prostate cancer receiving intermittent (IADT) versus continuous ADT (CADT).

METHODS

We searched Cochrane CENTRAL, PubMed/Medline, Embase, Web of Science, The National Cancer Institute Clinical Trials and The Clinical Trials Register of Trials Central, and Google Scholar from inception of each database through February 2016. References from published guidelines, reviews and other relevant articles were also considered. We selected randomized clinical trials comparing IADT versus CADT in patients with prostate cancer that reported data on cardiovascular events. Two reviewers performed the study selection, data abstraction and risk of bias assessment. We calculated risk ratios with the Mantel-Haenszel method, using random effect models. We assessed heterogeneity using I² index. The primary outcome was incidence of cardiovascular events. Secondary outcomes were thromboembolic events and cardiovascular-related mortality.

RESULTS

Out of 106 references, we included seven articles from six trials (4810 patients) published between 2009 and 2015. We observed no significant difference between intermittent versus continuous androgen deprivation with respect to cardiovascular events (risk ratio (RR): 0.95; confidence interval (CI) 95%=0.83-1.08; seven trials, 4810 patients) and thromboembolic events (RR: 1.05; CI 95%=0.85-1.30; three trials, 1816 patients). There was marginally significant difference with respect to cardiovascular-related mortality (RR: 0.85; CI 95%=0.71-1.00; five trials, 4170 patients).

CONCLUSIONS

Compared with CADT, IADT shows no difference in terms of cardiovascular events and thromboembolic events. However, there was an association between lower cardiovascular-related mortality and intermittent androgen deprivation.

Roles of Testosterone Replacement in Cardiac Ischemia-Reperfusion Injury

Testosterone is an anabolic steroid hormone, which is the major circulating androgen hormone in males. Testosterone levels decreasing below the normal physiological levels lead to a status known as androgen deficiency. Androgen deficiency has been shown to be a major risk factor in the development of several disorders, including obesity, metabolic syndrome, and ischemic heart disease. In the past decades, although several studies from animal models as well as clinical studies demonstrated that testosterone exerted cardioprotection, particularly during ischemia-reperfusion (I/R) injury, other preclinical and clinical studies have shown an inverse relationship between testosterone levels and cardioprotective effects. As a result, the effects of testosterone replacement on the heart remain controversial. In this review, reports regarding the roles of testosterone replacement in the heart following I/R injury are comprehensively summarized and discussed. At present, it may be concluded that chronic testosterone replacement at a physiological dose demonstrated cardioprotective effects, whereas acute testosterone replacement can cause adverse effects in the I/R heart.

Evolution of sexually dimorphic longevity in humans

Why do humans live longer than other higher primates? Why do women live longer than men? What is the significance of the menopause? Answers to these questions may be sought by reference to the mechanisms by which human aging might have evolved. Here, an evolutionary hypothesis is presented that could answer all three questions, based on the following suppositions. First, that the evolution of increased human longevity was driven by increased late-life reproduction by men in polygynous primordial societies. Second, that the lack of a corresponding increase in female reproductive lifespan reflects evolutionary constraint on late-life oocyte production. Third, that antagonistic pleiotropy acting on androgen-generated secondary sexual characteristics in men increased reproductive success earlier in life, but shortened lifespan. That the gender gap in aging is attributable to androgens appears more likely given a recent report of exceptional longevity in eunuchs. Yet androgen depletion therapy, now used to treat prostatic hyperplasia, appears to accelerate other aspects of aging (e.g. cardiovascular disease). One possibility is that low levels of androgens throughout life reduces aging rate, but late-life androgen depletion does not.

Cardiovascular events associated with androgen deprivation therapy in patients with prostate cancer: a systematic review and meta-analysis

CONTEXT

A recently published meta-analysis of randomized clinical trials (RCT) showed that androgen deprivation therapy (ADT) did not significantly increase cardiovascular mortality in prostate cancer patients. However, cardiovascular morbidity, which can impact quality of life, was not evaluated.

OBJECTIVE

To evaluate the risk of cardiovascular morbidity associated with ADT in patients with prostate cancer.

METHODS

We conducted a literature search from January 1960 to June 2012. RCT and large cohort studies that evaluated first-line endocrine therapy and ADT longer than 6 months were screened for inclusion.

RESULTS

In total, 126,898 patients were included in four cohort studies, and 10,760 patients were included in nine RCTs. Analysis of the RCTs showed no differences in the development of acute myocardial infarction (AMI) (OR 1.23; 95 % CI 0.92-1.64; I (2): 0 %) among the patients receiving ADT or not. The analysis of randomized studies that reported other nonfatal cardiovascular events demonstrated a significant increase in such events in the group receiving ADT (OR 1.55; 95 % CI 1.09-2.20; I (2): 0 %). When the large cohort studies were included in the analysis, an increased risk of AMI among men with ADT was found (OR 2.01, 95 % CI 1.90-2.13; I (2): 91,3 %).

CONCLUSION

The use of ADT in prostate cancer patients corresponded with a significant increase in cardiovascular morbidity associated with AMI and with nonfatal events. Therefore, ADT is linked to a significant negative impact on quality of life. Periodic cardiovascular evaluation is required for these patients.

[Observational survey of the French Urological Association evaluating intermittent hormonal modalities treatment in prostate cancer in France]

OBJECTIVE

To assess clinical practice of intermittent hormone therapy (IHT) among urologists members of the French Association of Urology.

METHODS

Internet-based observational survey evaluating IHT modalities in prostate cancer using questionnaire sent to 941 urologists.

RESULTS

Two hundred and sixty nine urologists participated in the survey (response rate 28.6 %) including 90.3 % prescribing IHT. The main reasons for IHT were improvement of quality of life in 94.2 %, clinical tolerance in 73.7 %, decreased costs and oncological equivalence in 44 %. The indications were localized prostate cancer (low risk 22.6 %, intermediate 19.8 %, high 14 %), locally advanced (59.7 %), metastatic (63.4 %), biochemical recurrence after local treatment (prostatectomy 62.1 %, radiotherapy 73.7 %). A PSA <2 ng/mL was considered as the threshold for androgen deprivation therapy break in 70 % of cases regardless of the IHT indication. The PSA threshold selected for the re-initiation of treatment was 4 ng/mL in 37.9 % and 10 ng/mL in 36.6 % of cases. The cycle of IHT was 6 months in 60 % of cases.

CONCLUSION

This survey provided a snapshot of the practice of IHT in France. Even in the absence of level of evidence 1 trials in the literature, most urologists used IHT in their clinical practice, for many indications, especially in case of biochemical recurrence after local treatment.

LEVEL OF PROOF

3.

Testosterone deficiency syndrome and cardiovascular health: An assessment of beliefs, knowledge and practice patterns of general practitioners and cardiologists in Victoria, BC

INTRODUCTION

Testosterone deficiency syndrome (TDS) has been shown to be an independent cardiovascular risk factor and a predisposing factor for metabolic syndrome. As general practitioners and cardiologists primarily care for these patients, we sought to assess their knowledge, beliefs and practice patterns with respect to TDS and cardiac health.

METHODS

We distributed a questionnaire to all 20 cardiologists and a cohort of 128 family practitioners in Victoria, British Columbia. Of the 13 questions, 10 assessed knowledge and beliefs on TDS and 3 assessed current practice patterns.

RESULTS

Most respondents believed that TDS is a medical condition (66.7%) and could negatively affect body composition (62%), but a similar majority was unsure whether it was a cardiac risk factor (66.7%). While most believed that testosterone replacement therapy (TRT) could improve exercise tolerance (62%), most were unsure if it was beneficial in cardiac patients. Cardiologists were significantly less likely to believe that TRT was beneficial in preventing recurrent myocardial infarction and improving myocardial perfusion (p = 0.0133, 0.00186, respectively). The vast majority (88%) did not screen cardiac patients for TDS. If a patient was identified as having TDS, only10% of those surveyed would refer these patients to a urologist.

CONCLUSION

Despite its prevalence in cardiac patients, TDS is not well-understood by general practitioners and cardiologists; they lack knowledge on its deleterious cardiovascular effects. In their role as men's health advocates, urologists should educate our colleagues regarding the correlation between TDS and cardiovascular mortality and risk factors. Limitations of this study include small sample size and restricted geographic scope.

Evaluation of primary androgen deprivation therapy in prostate cancer patients using the J-CAPRA risk score

Purpose:

To determine the influence of maximal androgen blockade (MAB) and non-MAB hormonal therapy with an luteinizing hormone releasing hormone (LHRH) analog on overall survival of prostate cancer patients in the Japan Study Group of Prostate Cancer (J-CaP) registry according to risk, as assessed using the novel J-CAPRA risk instrument. To undertake a multivariate analysis combining J-CAPRA risk score, type of hormonal therapy and comorbidities, in order to assess their impact on overall survival.

Methods:

The J-CaP database includes men in Japan diagnosed with any stage of prostate cancer between 2001 and 2003 and treated with primary androgen deprivation therapy (PADT), as monotherapy or in combination. A total of 26,272 men were enrolled and of these 19,265 were treated with PADT. This analysis was undertaken using the latest data set (30 April, 2010) including a total of 15,727 patients who received PADT and had follow-up data for periods ranging from 0 to 9.2 years.

Results:

MAB for prostate cancer patients with intermediate- or high-risk disease has a significant benefit in terms of overall survival compared with LHRH analog monotherapy or surgical castration alone. Better results may be achieved in older (≥75 years) patients. Patient comorbidities are an important factor in determining overall survival, notably in older patients, and should be considered when selecting therapy.

Conclusions:

Based on large-scale registry data, this report is the first to analyze the outcomes of MAB therapy in patients with prostate cancer at a wide range of disease stages. MAB therapy may provide significant survival benefits in intermediate- and high-risk patients.

Androgens and cardiovascular disease: Gender-related differences

Androgens are known to play a pivotal role in cardiovascular function. However, a definitive explanation as to how their impact differs between genders is yet to be provided. In this review, the existing studies on the link between androgens and cardiovascular disease have been analysed, with a particular focus on the gender-specific differences. Several studies agree that both direct and indirect effects of testosterone on cardiovascular function show a gender-related dimorphism. Consistently, men and women display different responses to androgen supplementation treatment. Post-menopausal women may particularly benefit from testosterone supplementation therapy. Future studies should further clarify the optimal dose and route of administration of testosterone, and more women should be included in clinical trials, in order to identify novel gender-specific targets, and finally to develop therapeutic strategies.

Triptorelin in the management of prostate cancer

Among the therapies to achieve medical castration, gonadotropin-releasing hormone (GnRH) agonists have better safety profiles than estrogens and anti-androgens. In addition, slow-release formulations of GnRH agonists offer patients flexibility, improve quality of life and eventually reduce cost. To illustrate the role of medical castration in prostate cancer, this paper reviews data on the GnRH agonist triptorelin long-duration and shorter-duration formulations. A similar proportion of patients achieved and maintained castration levels of serum testosterone (≤50 ng/dl) with all triptorelin formulations. Moreover, using a stricter definition of medical castration (serum testosterone <20 ng/dl), castration was maintained in >90% of patients with the 6-month triptorelin formulation. The new formulation was also well-tolerated, whilst being more convenient for patients. This short review assesses the role of this GnRH agonist in the treatment of prostate cancer.

Timing of androgen deprivation therapy use and fracture risk among elderly men with prostate cancer in the United States

PURPOSE

Fractures are a recognized consequence of androgen deprivation therapy (ADT); however, less is known about the incidence of fracture in relation to the timing of ADT use or the impact of fracture on mortality in men with prostate cancer.

METHODS

Using data from the Surveillance, Epidemiology, and End Results-Medicare linked database, we estimated adjusted hazard ratios (aHRs) using time-dependent Cox regression for fracture incidence related to the recency of exposure and dose among prostate cancer patients on gonadotropin-releasing hormone (GnRH) agonists, as well as mortality associated with fractures.

RESULTS

In our cohort of 80 844 patients, ADT was associated with an increased rate of fracture in both non-metastatic patients (aHR = 1.34; 95% confidence interval [CI] = 1.29-1.39) and metastatic patients (aHR = 1.51; 95%CI = 1.36-1.67). Fracture rates increased with increasing cumulative GnRH dose but decreased with increasing number of months since last use in each dose category. The mortality rate doubled for men experiencing a fracture after their diagnosis compared with that for men who did not experience a fracture (aHR = 2.05; 95%CI = 1.98-2.12).

CONCLUSIONS

ADT in elderly men with prostate cancer increased the incidence of fractures, and the effect appears to diminish with increasing time since the last dose of a GnRH agonist. Experiencing a fracture after the diagnosis of prostate cancer was associated with decreased survival.

Hypogonadism as a risk factor for cardiovascular mortality in men: a meta-analytic study

OBJECTIVE

To verify whether hypogonadism represents a risk factor for cardiovascular (CV) morbidity and mortality and to verify whether testosterone replacement therapy (TRT) improves CV parameters in subjects with known CV diseases (CVDs).

DESIGN

Meta-analysis.

METHODS

An extensive Medline search was performed using the following words 'testosterone, CVD, and males'. The search was restricted to data from January 1, 1969, up to January 1, 2011.

RESULTS

Of the 1178 retrieved articles, 70 were included in the study. Among cross-sectional studies, patients with CVD have significantly lower testosterone and higher 17-β estradiol (E(2)) levels. Conversely, no difference was observed for DHEAS. The association between low testosterone and high E(2) levels with CVD was confirmed in a logistic regression model, after adjusting for age and body mass index (hazard ratio (HR)=0.763 (0.744-0.783) and HR=1.015 (1.014-1.017), respectively, for each increment of total testosterone and E(2) levels; both P<0.0001). Longitudinal studies showed that baseline testosterone level was significantly lower among patients with incident overall- and CV-related mortality, in comparison with controls. Conversely, we did not observe any difference in the baseline testosterone and E(2) levels between case and controls for incident CVD. Finally, TRT was positively associated with a significant increase in treadmill test duration and time to 1 mm ST segment depression.

CONCLUSIONS

Lower testosterone and higher E(2) levels correlate with increased risk of CVD and CV mortality. TRT in hypogonadism moderates metabolic components associated with CV risk. Whether low testosterone is just an association with CV risk, or an actual cause-effect relationship, awaits further studies.

Gonadotropin-releasing hormone blockers and cardiovascular disease risk: analysis of prospective clinical trials of degarelix

PURPOSE

We investigated associations of baseline cardiovascular disease risk profile, dosing regimen and treatment duration with incident cardiovascular disease events during androgen deprivation therapy with degarelix in patients with prostate cancer.

MATERIALS AND METHODS

Data on 1,704 men who participated in a total of 9 clinical trials were pooled for analysis. Patients received treatment with 1-month (20 to 240 mg) or 3-month (240 to 480 mg) doses of degarelix for an average of 22 months. End points were ischemic heart disease, cerebrovascular disorders, arterial thrombotic/embolic events and intermittent claudication.

RESULTS

First time cardiovascular disease events were reported in 92 men in the year before study entry and in 168 after degarelix treatment. Event rates were similar before and after degarelix treatment in the total population (5.5 vs 6.1/100 person-years, p = 0.45) and in men without cardiovascular disease (5.6 vs 4.3/100 person-years, p = 0.11). In contrast, event rates appeared higher after degarelix treatment in men with cardiovascular disease at baseline (5.3 to 10.5 events per 100 person-years, p = 0.0013). On multivariate analysis cardiovascular disease at baseline was the strongest independent predictor of events, followed by older age, alcohol abstinence and obesity (each p <0.05). Degarelix dose and schedule were not independently associated with cardiovascular disease events.

CONCLUSIONS

In men with prostate cancer observed rates of cardiovascular disease events were similar before and after degarelix treatment. Events were largely confined to men with preexisting cardiovascular disease and further modulated by age and modifiable risk factors. Randomized, controlled trials and longer followup are key to fully clarify the comparative safety of gonadotropin-releasing hormone antagonists vs agonists.

Gender differences in artery wall biomechanical properties throughout life

Elevated large artery stiffness and pulse pressure have emerged as important risk factors for cardiovascular disease. The genders differ in large artery biomechanical properties throughout the lifespan with females displaying higher stiffness than males during the prepubertal years and a dramatic increase after menopause. Males on the other hand experience an increase in arterial stiffness postpuberty and a linear increase thereafter, suggesting that females have intrinsically stiffer large arteries than males, but that such effects are mitigated by sex steroids during the reproductive years. This review discusses anthropometric and sex steroid influences on gender differences in large artery stiffness and pressure dynamics from childhood to senescence. In particular, the sex-specific effects of estrogen, progesterone and testosterone on vascular structure and function and how these influence arterial stiffness are explored. These factors may contribute in part to the observed gender differences in the pathophysiology and clinical manifestations of cardiovascular disease.

Cardiac and cognitive effects of androgen deprivation therapy: are they real?

With androgen deprivation therapy being used ever earlier and longer in the course of prostate cancer, concerns have emerged about a variety of adverse effects, including cardiovascular disease and cognitive dysfunction. Conflicting data in both areas have led to controversy and confusion. Here, we review published data in an attempt to clarify those issues.

Androgen-suppression therapy for prostate cancer and the risk of death in men with a history of myocardial infarction or stroke

OBJECTIVE

To examine the effect of short-course androgen-suppression therapy (AST) before brachytherapy on all-cause mortality (ACM) rates, stratified by the presence or absence of a history of myocardial infarction (MI) or stroke. AST is used to reduce prostate size to enable men with favourable-risk prostate cancer to undergo brachytherapy, but no disease-specific benefit has been reported for this practice, and AST use has been associated with an increased risk of ACM in some men with pre-existing cardiovascular disease.

PATIENTS AND METHODS

The study comprised 12792 men with favourable-risk disease, i.e. a prostate-specific antigen (PSA) level of <20 ng/mL, Gleason score ≤7 and clinical category ≤T2c, treated between 1991 and 2007 at community-based medical centres with brachytherapy ± neoadjuvant AST. Multivariable Cox regression analysis was used to assess whether there were significant associations between AST use in men with a history of MI or stroke and the risk of ACM, adjusting for age, treatment year, and known prognostic factors of prostate cancer.

RESULTS

After a median (interquartile range) follow-up of 3.8 (2.0-5.9) years there were 1557 deaths. The risk of ACM was lower in men with no history of MI or stroke than in those with this history, whether AST was used (adjusted hazard ratio 0.79, 95% confidence interval 0.67-0.92; P= 0.003) or not (0.74, 0.65-0.85; P < 0.001). However, men with a history of MI or stroke treated with AST had a greater risk of ACM than those not treated with AST (1.2, 1.05-1.38; P= 0.008).

CONCLUSION

The use of short-course AST in men with a history of MI or stroke is associated with a greater risk of ACM in men with favourable-risk prostate cancer.

Gender differences in the cardiovascular effect of sex hormones

The higher incidence of cardiovascular disease in men than in women of similar age, and the menopause-associated increase in cardiovascular disease in women, has led to speculation that gender-related differences in sex hormones have a key role in the development and evolution of cardiovascular disease. Compelling data have indicated that sex differences in vascular biology are determined not only by gender-related differences in sex steroid levels, but also by gender-specific tissue and cellular differences that mediate sex-specific responses. In this Review, we describe the sex-specific effects of estrogen and testosterone on cardiovascular risk, direct vascular effects of these sex hormones, and how these effects influence development of atherosclerosis. Cardiovascular effects of exogenous hormone administration are also discussed. Importantly, evidence has indicated that estrogens alone or in combination with progestins in postmenopausal women increase cardiovascular risk if started late after menopause, but that it possibly has beneficial cardiovascular effects in younger postmenopausal women, although data on long-term testosterone therapy are lacking. Hormone therapy should not be considered solely for primary prevention or treatment of cardiovascular disease at this time.