An exercise trial targeting African-American women with metabolic syndrome and at high risk for breast cancer: Rationale, design, and methods

The Effect of a 6-Month Exercise Intervention Trial on Allostatic Load in Black Women at Increased Risk for Breast Cancer: the FIERCE Study

BACKGROUND

Allostatic load comprises cardiovascular, metabolic, and inflammatory markers, which is characterized by abdominal obesity, high blood glucose levels, impaired glucose tolerance, dyslipidemia, and hypertension and associated with an increased risk in breast cancer.

METHODS

The study was a 6-month, 3-arm randomized controlled trial of two moderate-intensity exercise interventions (compared with a control group) among obese, physically inactive, postmenopausal Black women aged 45 to 65 years, who were at increased risk for breast cancer based on the CARE model. Two hundred thirteen participants were randomly assigned to (1) supervised, facility-based aerobic exercise intervention (n = 73), (2) home-based exercise intervention (n = 69), or (3) a wait-listed control group (n = 71). The intervention effects of exercise on allostatic load were examined with intent-to-treat analyses using generalized linear models.

RESULTS

It was revealed that statistically significant decreases in allostatic load over the 6-month period for both exercise intervention groups (i.e., home-based and supervised arms) compared to the controls were observed among the total population, pc-h = 0.023 and pc-s = 0.035, as well as among women with a family history of breast cancer, pc-h = 0.006 and pc-s = 0.012.

CONCLUSIONS

Short-term aerobic activity improved allostatic load scores in metabolically unhealthy postmenopausal Black women at increased risk for cancer.

TRIAL REGISTRATION

Clinical trial registration number NCT02103140.

Dietary fiber intake and metabolic syndrome in postmenopausal African American women with obesity

Fiber intake may be associated with lower risk of metabolic syndrome (MetS) but data from metabolically unhealthy African American women is sparse. We examined the association of dietary fiber intake and MetS among postmenopausal African American women with obesity. Baseline cross-sectional data from the Focused Intervention on Exercise to Reduce CancEr (FIERCE) trial of 213 women (mean age 58.3 years) were used. Dietary intake was assessed by Food Frequency Questionnaires (FFQs). Multivariate linear and logistic regressions were performed to estimate associations of MetS with fiber intake and adherence to dietary fiber intake guidelines, respectively. Mean daily fiber intake was (10.33 g/1000kcal) in women with impaired metabolic health. We observed an inverse association of total fiber intake with MetS. One unit increase in energy-adjusted fiber intake was associated with a 0.10 unit decrease in the MetS z-score (p = 0.02). Similar results were obtained for both soluble and insoluble fiber. In multivariate-adjusted analyses, participants not adherent to fiber intake recommendations were more likely to have MetS as compared to those reporting intakes in the recommended range (adjusted odds ratio 4.24, 95% CI: 1.75, 10.30). Of the MetS components, high fasting glucose and high triglycerides were all associated with lower intake of fiber. Study participants who consumed a higher amount of fiber had a better overall metabolic profile and were less likely to have MetS in our cross-sectional analysis of postmenopausal African American women with obesity and unhealthy metabolic profiles.

Ethnicity and Metabolic Syndrome: Implications for Assessment, Management and Prevention

The metabolic syndrome (MetS) is a constellation of cardiometabolic risk factors that identifies people at increased risk for type 2 diabetes and cardiovascular disease. While the global prevalence is 20%–25% of the adult population, the prevalence varies across different racial/ethnic populations. In this narrative review, evidence is reviewed regarding the assessment, management and prevention of MetS among people of different racial/ethnic groups. The most popular definition of MetS considers race/ethnicity for assessing waist circumference given differences in visceral adipose tissue and cardiometabolic risk. However, defining race/ethnicity may pose challenges in the clinical setting. Despite 80% of the world’s population being of non-European descent, the majority of research on management and prevention has focused on European-derived populations. In these studies, lifestyle management has proven an effective therapy for reversal of MetS, and randomised studies are underway in specific racial/ethnic groups. Given the large number of people at risk for MetS, prevention efforts need to focus at community and population levels. Community-based interventions have begun to show promise, and efforts to improve lifestyle behaviours through alterations in the built environment may be another avenue. However, careful consideration needs to be given to take into account the unique cultural context of the target race/ethnic group.

The weight of obesity in breast cancer progression and metastasis: Clinical and molecular perspectives

The escalating epidemic of overweight and obesity is currently recognized as one of the most significant health and economic concern worldwide. At the present time, over 1.9 billion adults and more than 600 million people can be, respectively, classified as overweight or obese, and numbers will continue to increase in the coming decades. This alarming scenario implies important clinical implications since excessive adiposity can progressively cause and/or exacerbate a wide spectrum of co-morbidities, including type 2 diabetes mellitus, hypertension, cardiovascular disease, and even certain types of cancer, including breast cancer. Indeed, pathological remodelling of white adipose tissue and increased levels of fat-specific cytokines (mainly leptin), as a consequence of the obesity condition, have been associated with several hallmarks of breast cancer, such as sustained proliferative signaling, cellular energetics, inflammation, angiogenesis, activating invasion and metastasis. Different preclinical and clinical data have provided evidence indicating that obesity may worsen the incidence, the severity, and the mortality of breast cancer. In the present review, we will discuss the epidemiological connection between obesity and breast cancer progression and metastasis and we will highlight the candidate players involved in this dangerous relationship. Since the major cause of death from cancer is due to widespread metastases, understanding these complex mechanisms will provide insights for establishing new therapeutic interventions to prevent/blunt the effects of obesity and thwart breast tumor progression and metastatic growth.

Effect of exercise on metabolic syndrome in black women by family history and predicted risk of breast cancer: The FIERCE Study

BACKGROUND

This study examined the effects of supervised and home-based exercise interventions on changes in metabolic syndrome (MetS) according to breast cancer risk (high vs low) in black women enrolled in the Focused Intervention on Exercise to Reduce Cancer (FIERCE) trial.

METHODS

Postmenopausal, obese, metabolically unhealthy black women, 45 to 65 years old, were randomized to supervised aerobic exercise (73 women), home-based walking-based exercise (69 women), or a control arm (71 women). Participants in the exercise arms underwent a 6-month intervention with study assessments conducted at the baseline and 6 months. The primary outcome measure was MetS (fasting glucose, waist circumference, blood pressure, serum triglycerides, and high-density lipoprotein [HDL]). The intervention effects on MetS, stratified by breast cancer risk as measured by the family history of breast cancer and model-based projected breast cancer risk, were examined with intent-to-treat analyses using generalized estimating equation models.

RESULTS

Among women with a family history of breast cancer, the exercise arms had lower mean MetS z scores, which suggested an improvement in the metabolic profile, than controls at 6 months (controls, + 0.55; home-based arm, -0.97, P < .01; supervised arm, -0.89, P < .01). Stratified analyses by projected breast cancer risk suggested similar but statistically nonsignificant findings, with those at high risk having more favorable changes in the MetS z score in the exercise arms versus the control arm. These changes were primarily attributable to changes in blood pressure, triglycerides, and HDL.

CONCLUSIONS

Short-term aerobic activity regimens may improve the metabolic profile and thereby reduce breast cancer risk in obese, metabolically unhealthy black women at high risk for cancer. © 2018 American Cancer Society.

Predicting Physical Activity Behavior in African American Females: UsingMulti Theory Model

Background: Despite physical activity having several benefits, a considerable number of Americans donot engage in sufficient exercise. Among the high-risk groups are African American women. A recenttheory, multi theory model (MTM) for health behavior change can be used to develop effectiveinterventions. The objective of this research was to test MTM in its ability to predict physical activitybehavior in African American women.

Study design: A cross-sectional study.

Methods: African American women aged 18 yr and older were recruited at various locations (primarilychurches) of Jackson, a large city in Central Mississippi instead of southern Mississippi to participate inthis cross-sectional study in 2016. The valid and reliable survey was administered to a G*Power calculatedquota sample of 156 women either in person or via a Qualtrics link sent through an e-mail.

Results: The regression analysis revealed that 32.7% of the variance in initiating physical activity behaviorwas predicted by participatory dialogue, behavioral confidence, and changes in physical environment.Sustenance of physical activity behavior was predicted up to 38.8% by emotional transformation andchanges in social environment.

Conclusions: MTM appears to be a robust theory in its application for changing physical activity behaviorin African American women. This theory must be reified and empirically tested with this population.

The effect of a randomized controlled physical activity trial on health related quality of life in metabolically unhealthy African-American women: FIERCE STUDY

PURPOSE

African-American women (AAW) are more likely to be metabolically unhealthy than White women (WW). Metabolic syndrome (MetS) is associated with increased breast cancer risk and mortality from breast cancer is greater in AAW compared to WW. Data show MetS affects health-related quality of life (HRQoL). Exercise studies report improvements in MetS, however, no study to date has examined HRQoL in metabolically unhealthy AAW enrolled in an exercise trial.

METHODS

This report examined the effect of a 6-month, 3-arm (supervised exercise, home-based exercise, control) randomized exercise controlled trial on HRQoL among 213 obese, metabolically unhealthy, postmenopausal AAW at high risk for breast cancer.

RESULTS

Certain baseline participant characteristics were related to baseline HRQoL dimensions. The "exercise group" (supervised group combined with the home-based group) showed significantly greater improvement in health change scores (M = 13.6, SD = 3.1) compared to the control group (M = 0.7, SD = 4.4) (p = 0.02) over the 6-month study period. There were no significant differences in HRQoL change scores between the 3 study groups, however, although non-significant, data indicated most HRQoL change scores were more favorable in the supervised group.

CONCLUSION

While significant improvement occurred in health change scores in the combined supervised and home-based group compared to the control group, we did not observe any significant differences on HRQoL change scores between all three study groups. However, while non-significant, there was a trend for more favorable HRQoL change scores in the supervised group versus the home-based and control groups. Additional research is needed to further explore this topic.

MicroRNAs in cancer therapeutics: "from the bench to the bedside"

MicroRNAs (miRNAs) are non-coding RNA transcripts that regulate physiological processes by targeting proteins directly. Their involvement in research has been robust, and evidence of their regulative functions has granted them the title: master regulators of the human genome. In cancer, they are considered important therapeutic agents, due to the fact that their aberrant expression contributes to disease development, progression, metastasis, therapeutic response and patient overall survival. This has endeavored fields of biomedical sciences to invest in developing and exploiting miRNA-based therapeutics thoroughly. Herein we highlight relevant ongoing/open clinical trials involving miRNAs and cancer.