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Christy G Woolcott,
Kerry S Courneya,
Norman F Boyd,
Martin J Yaffe,
Anne McTiernan,
Rollin Brant, Charlotte A Jones,
Frank Z Stanczyk,
Tim Terry,
Linda S Cook,
Qinggang Wang,
Christine M Friedenreich
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ABSTRACT: The biological mechanisms underlying the relationship between mammographic density and breast cancer risk are unknown. Our objective was to examine the association between mammographic density and circulating factors that are putative breast cancer intermediate endpoints. Biologic data from a year-long aerobic exercise intervention trial conducted in 302 postmenopausal women aged 50-74 years were analyzed. Sex hormones, markers of glucose homeostasis, inflammatory markers, and adipokines were assayed in fasting blood drawn at baseline and after 1 year. Area and volumetric measurements of mammographic dense fibroglandular and nondense fatty tissue were made. Multiple linear regression was used to examine the association between the circulating factors and mammographic measures and partial correlations were estimated. Mammographic nondense volume was positively correlated with concentrations of estradiol (r = 0.28), estrone (r = 0.13), insulin (r = 0.41), glucose (r = 0.15), leptin (r = 0.49), and C-reactive protein (r = 0.22), and negatively correlated with sex hormone binding globulin (r = -0.30) and adiponectin (r = -0.12) but correlations became null after adjustment for overall body adiposity as represented by body mass index and waist circumference. With adjustment for overall adiposity, mammographic dense volume, a measure that represents fibroglandular tissue, was negatively correlated with leptin (r = -0.19) and C-reactive protein (r = -0.19). As expected, circulating factors originating from or correlated with adipose tissue were also correlated with mammographic measures of breast adipose tissue, but not after adjustment for overall body adiposity. Interpreting correlations between adiposity-derived factors and mammographic measures whose validity may be affected by adiposity is problematic. To rectify this problem, future studies with very good measures of the volume of fibroglandular tissue in the breast will be necessary.
Breast Cancer Research and Treatment 04/2013; · 4.43 Impact Factor
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ABSTRACT: BACKGROUND: South Asian Canadians experience disproportionately high rates of cardiovascular disease (CVD). The goal of this qualitative study was to determine the feasibility of implementing a sustainable, culturally adapted, community-based CVD risk factor screening program for this population. METHODS: South Asians (>= 45 years) in Calgary, Alberta underwent opportunistic cardiovascular risk factor screening by lay trained volunteers at local religious facilities. Those with elevated blood pressure (BP) or >= 1 risk factor underwent point of care cholesterol testing, 10-year CVD risk calculation, counseling, and referral to family physicians and local culturally tailored chronic disease management (CDM) programs. Participants were invited for re-screening and were surveyed about health system follow-up, satisfaction with the program and suggestions for improvement. Changes in risk factors from baseline were estimated using McNemar's test (proportions) and paired t-tests (continuous measures). RESULTS: Baseline assessment was completed for 238 participants (median age 64 years, 51% female). Mean TC, HDL and TC/HDL were 5.41 mmol/L, 1.12 mmol/L and 4.7, respectively. Mean systolic and diastolic blood pressures (mmHg) were 129 and 75 respectively. Blood pressure and TC/HDL ratios exceeded recommended targets in 36% and 58%, respectively, and 76% were at high risk for CVD. Ninety-nine participants (47% female) attended re-screening. 82% had accessed health care providers, 22% reported medication changes and 3.5% had attended the CDM programs. While BP remained unchanged, TC and TC/HDL decreased and HDL increased significantly (mean differences: -0.52 mmol/L, -1.04 and +0.07 mmol/L, respectively). Participants were very satisfied (80%) or satisfied (20%) with the project. Participants suggested screening sessions and CDM programs be more accessible by: delivering evening or weekends programs at more sites, providing transportation, offering multilingual programs/translation assistance, reducing screening wait times and increasing numbers of project staff. CONCLUSIONS: SA-CHAMP demonstrated the feasibility and value of implementing a lay volunteer--led, culturally adapted, sustainable community-based CVD risk factor screening program in South Asian places of worship in Calgary, Alberta, Canada. Subsequent screening and CDM programs were refined based on the learnings from this study. Further research is needed to determine physician and patient factors associated with uptake of and adherence to risk reduction strategies.
BMC Public Health 02/2013; 13(1):160. · 2.00 Impact Factor
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ABSTRACT: Chronic low-grade inflammation is a possible risk factor for cancer that may be modifiable with long-term exercise. Very few randomized controlled trials (RCT) have studied the isolated effects of exercise on low-grade inflammation exclusively in postmenopausal women. The Alberta Physical Activity and Breast Cancer Prevention Trial, a 2-armed RCT in healthy postmenopausal women, examined how 1 year of moderate to vigorous aerobic exercise, compared with usual inactivity, influenced circulating inflammatory markers. Baseline, 6-month, and 12-month serum was analyzed by direct chemiluminescent immunoassays to measure high sensitivity C-reactive protein (CRP) and ELISAs to measure interleukin 6 (IL-6) and TNF-α. Intention to treat analyses were conducted with linear mixed models. Statistically significant differences in CRP were observed over 12 months for exercisers versus controls (treatment effect ratio = 0.87, 95% CI = 0.79-0.96, P = 0.005), but not in IL-6 or TNF-α. A statistically significant trend (P(trend) = 0.021) of decreasing CRP with increasing exercise adherence and stronger intervention effects on CRP in women with higher baseline physical fitness (P(heterogeneity) = 0.040) was found. The intervention effect on CRP became statistically nonsignificant with adjustment for dietary fiber intake change and seemed to be mediated by fat loss. Low-grade inflammation may be lowered with exercise, but confounding by dietary intake occurred and should be considered in future studies. Further trials are needed to corroborate our findings about the optimal dose of exercise required to lower CRP levels and effect modification of CRP changes by levels of body fatness and fitness.
Cancer Prevention Research 01/2012; 5(1):98-108. · 4.91 Impact Factor
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ABSTRACT: Indo-Asians in Canada are at increased risk for cardiovascular diseases. There is a need for cultural and language specific educational materials relating to this risk. During this project we developed and field tested the acceptability of a hypertension public education pamphlet tailored to fit the needs of an at risk local Indo-Asian population, in Calgary, Alberta, Canada.
A community health board representing Calgary's Indo-Asian communities identified the culturally specific educational needs and language preferences of the local population. An adaptation of an existing English language Canadian Public Hypertension Recommendations pamphlet was created considering the literacy and translation challenges. The adapted pamphlet was translated into four Indo-Asian languages. The adapted pamphlets were disseminated as part of the initial educational component of a community-based culturally and language-sensitive cardiovascular risk factor screening and management program. Field testing of the materials was undertaken when participants returned for program follow-up seven to 12 months later.
Fifty-nine English-speaking participants evaluated and confirmed the concept validity of the English adapted version. 28 non-English speaking participants evaluated the Gujarati (N = 13) and Punjabi (N = 15) translated versions of the adapted pamphlets. All participants found the pamphlets acceptable and felt they had improved their understanding of hypertension.
Involving the target community to identify health issues as well as help to create culturally, language and literacy sensitive health education materials ensures resources are highly acceptable to that community. Minor changes to the materials will be needed prior to formal testing of hypertension knowledge and health decision-making on a larger scale within this at risk community.
BMC Public Health 01/2011; 11:24. · 2.00 Impact Factor
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Christine M Friedenreich,
Heather K Neilson,
Christy G Woolcott,
Anne McTiernan,
Qinggang Wang,
Rachel Ballard-Barbash, Charlotte A Jones,
Frank Z Stanczyk,
Rollin F Brant,
Yutaka Yasui,
Melinda L Irwin,
Kristin L Campbell,
Margaret L McNeely,
Kristina H Karvinen,
Kerry S Courneya
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ABSTRACT: Physical activity is a known modifiable lifestyle means for reducing postmenopausal breast cancer risk, but the biologic mechanisms are not well understood. Metabolic factors may be involved. In this study, we aimed to determine the effects of exercise on insulin resistance (IR) indicators, IGF1, and adipokines in postmenopausal women. The Alberta Physical Activity and Breast Cancer Prevention Trial was a two-armed randomized controlled trial in postmenopausal, inactive, cancer-free women. A year-long aerobic exercise intervention of 225 min/week (n=160) was compared with a control group asked to maintain usual activity levels (n=160). Baseline, 6- and 12-month serum levels of insulin, glucose, IGF1, IGF-binding protein 3 (IGFBP3), adiponectin, and leptin were assayed, and after data collection, homeostasis model assessment of IR (HOMA-IR) scores were calculated. Intention-to-treat analyses were performed using linear mixed models. The treatment effect ratio (TER) of exercisers to controls was calculated. Data were available on 308 (96.3%) women at 6 months and 310 (96.9%) women at 12 months. Across the study period, statistically significant reductions in insulin (TER=0.87, 95% confidence interval (95% CI)=0.81-0.93), HOMA-IR (TER=0.86, 95% CI=0.80-0.93), and leptin (TER=0.82, 95% CI=0.78-0.87), and an increase in the adiponectin/leptin ratio (TER=1.21, 95% CI=1.13-1.28) were observed in the exercise group compared with the control group. No significant differences were observed for glucose, IGF1, IGFBP3, adiponectin or the IGF1/IGFBP3 ratio. Previously inactive postmenopausal women who engaged in a moderate-to-vigorous intensity exercise program experienced changes in insulin, HOMA-IR, leptin, and adiponectin/leptin that might decrease the risk for postmenopausal breast cancer.
Endocrine Related Cancer 01/2011; 18(3):357-69. · 4.36 Impact Factor
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ABSTRACT: Although high mammographic density is a risk factor for postmenopausal breast cancer, its etiology remains unclear. We examined whether serum and dietary cholesterol, which increase breast cancer risk and are involved in endogenous estrogen formation, were associated with increased mammographic density. We conducted a cross-sectional analysis of 302 healthy, sedentary postmenopausal women, aged 50-74 years, enrolled in the Alberta Physical Activity and Breast Cancer Prevention Trial between 2003 and 2006. In multiple linear regression models, no significant associations were observed between serum lipids and percent density or dense tissue area (Percent density: b (change in square root percent density per unit change in cholesterol level) = -0.06 (95%CI = -0.26 to 0.13); b = 0.06 (95%CI = -0.48 to 0.61); and b = -0.11 (95%CI = -0.33 to 0.10) for total cholesterol, high-, and low-density lipoprotein, respectively; similar results found for dense area). Alcohol consumption modified the association between triglycerides and percent density (>1 drink/day: b = -0.94 (95%CI = -1.79 to -0.10); ≤ 1 drink/day: b = 0.19 (95%CI = -0.12 to 0.50); and no alcohol consumption: b = 0.15 (95%CI = -0.44 to 0.73). We found no evidence indicating any association between dietary and serum cholesterol levels and mammographic density.
Breast Cancer Research and Treatment 05/2010; 125(1):181-9. · 4.43 Impact Factor
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Christy G Woolcott,
Kerry S Courneya,
Norman F Boyd,
Martin J Yaffe,
Tim Terry,
Anne McTiernan,
Rollin Brant,
Rachel Ballard-Barbash,
Melinda L Irwin, Charlotte A Jones,
Sony Brar,
Kristin L Campbell,
Margaret L McNeely,
Kristina H Karvinen,
Christine M Friedenreich
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ABSTRACT: The Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial examined the influence of aerobic exercise on biological factors that are associated with breast cancer risk. Mammographic density, a secondary outcome, is reported here.
The ALPHA Trial was a parallel group randomized controlled trial conducted between May 2003 and July 2007. Postmenopausal, sedentary women ages 50 to 74 years (n = 320) were evenly randomized to aerobic exercise (45 minutes, 5 days per week) or control (usual life-style) for 1 year. Dense fibroglandular tissue and nondense fatty tissue were measured from mammograms at baseline and 1 year using computer-assisted thresholding software for area measurements and a new technique that relies on the calibration of mammography units with a tissue-equivalent phantom for volumetric measurements.
Nondense volume decreased in the exercise group relative to the control group (difference between groups = -38.5 cm(3); 95% confidence interval, -61.6 to 15.4; P = 0.001). Changes in total body fat accounted for this decrease. Changes in dense area and dense volume, measures that have previously been associated with breast cancer risk, were not significantly different between the groups (P > or = 0.26).
Achieving changes in mammographic measures may require more exercise or a study population with higher baseline levels of sex hormones or a wider range of mammographic density. The data from this study, however, suggest that the protective effect of exercise on breast cancer risk may operate through a mechanism other than mammographic density.
Cancer Epidemiology Biomarkers & Prevention 03/2010; 19(4):1112-21. · 4.12 Impact Factor
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Christine M Friedenreich,
Christy G Woolcott,
Anne McTiernan,
Rachel Ballard-Barbash,
Rollin F Brant,
Frank Z Stanczyk,
Tim Terry,
Norman F Boyd,
Martin J Yaffe,
Melinda L Irwin, Charlotte A Jones,
Yutaka Yasui,
Kristin L Campbell,
Margaret L McNeely,
Kristina H Karvinen,
Qinggang Wang,
Kerry S Courneya
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ABSTRACT: We examined how an aerobic exercise intervention influenced circulating estradiol, estrone, sex hormone-binding globulin (SHBG), androstenedione, and testosterone levels, which may be involved in the association between physical activity and breast cancer risk.
A two-center, two-arm randomized controlled trial of exercise was conducted in 320 postmenopausal, sedentary women age 50 to 74 years. Participants were randomly assigned to a 1-year aerobic exercise intervention of 225 min/wk (n = 160) or to a control group who maintained their usual level of activity (n = 160). Baseline, 6-month, and 12-month assessments of estrone, estradiol, androstenedione, and testosterone were quantified by radioimmunoassay after extraction, and SHBG was quantified by an immunometric assay. Intent-to-treat analyses were performed using linear mixed models.
Blood data were available on 309 women (96.6%) at 12 months. Women in the intervention group exercised an average of 3.6 d/wk for 178 min/wk. At 12 months, statistically significant reductions in estradiol (treatment effect ratio [TER] = 0.93; 95% CI, 0.88 to 0.98) and free estradiol (TER = 0.91; 95% CI, 0.87 to 0.96) and increases in SHBG (TER = 1.04; 95% CI, 1.02 to 1.07) were observed in the exercise group compared with the control group. No significant differences in estrone, androstenedione, and testosterone levels were observed between exercisers and controls at 12 months.
This trial found that previously sedentary postmenopausal women can adhere to a moderate- to vigorous-intensity exercise program that results in changes in estradiol and SHBG concentrations that are consistent with a lower risk for postmenopausal breast cancer.
Journal of Clinical Oncology 02/2010; 28(9):1458-66. · 18.37 Impact Factor
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ABSTRACT: Homelessness [and poverty] is rapidly escalating across North America and is associated with dire implications for public health and our health care systems. Both are compelling states of existence affecting all ages, ethnicities and both genders. Homelessness frequently evolves through a complex interaction of factors that are both internal and external to the individual themselves. Once homeless, equitable access to both preventative and remedial health care is lacking and is associated with a higher than average burden of cardiovascular disease [CVD] risk factors, morbidity and mortality and is accompanied by disproportionately high health care costs. The emergence of limited, small scale programs aimed at addressing the unique health and social needs of the homeless is encouraging. However, there has been inadequate commitment at the National, State or Provincial and local levels to implement policies and dedicate funding and resources to the expansion of such "individual level" interventions into comprehensive programs that deliver sustainable, integrated prevention and services, especially with regard to CVD. The long-term solutions that address the links between homelessness and CVD lie in preventing homelessness and reversing the trends in our health care system that create disparities for lower socioeconomic status [SES] and homeless individuals.
Current Cardiology Reviews 01/2009; 5(1):69-77.
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ABSTRACT: Blood pressure (BP) control in patients with diabetes mellitus is difficult to achieve and current patterns are suboptimal. Given increasing problems with access to primary care physicians, community pharmacists and nurses are well positioned to identify and observe these patients. This study aimed to determine the efficacy of a community-based multidisciplinary intervention on BP control in patients with diabetes mellitus.
We performed a randomized controlled trial in 14 community pharmacies in Edmonton, Alberta, Canada, of patients with diabetes who had BPs higher than 130/80 mm Hg on 2 consecutive visits 2 weeks apart. Care from a pharmacist and nurse team included a wallet card with recorded BP measures, cardiovascular risk reduction education and counseling, a hypertension education pamphlet, referral to the patient's primary care physician for further assessment or management, a 1-page local opinion leader-endorsed evidence summary sent to the physician reinforcing the guideline recommendations for the treatment of hypertension and diabetes, and 4 follow-up visits throughout 6 months. Control-arm patients received a BP wallet card, a pamphlet on diabetes, general diabetes advice, and usual care by their physician. The primary outcome measure was the difference in change in systolic BP between the 2 groups at 6 months.
A total of 227 eligible patients were randomized to intervention and control arms between May 5, 2005, and September 1, 2006. The mean (SD) patient age was 64.9 (12.1) years, 59.9% were male, and the mean (SD) baseline systolic/diastolic BP was 141.2 (13.9)/77.3 (8.9) mm Hg at baseline. The intervention group had an adjusted mean (SE) greater reduction in systolic BP at 6 months of 5.6 (2.1) mm Hg compared with controls (P = .008). In the subgroup of patients with a systolic BP greater than 160 mm Hg at baseline, BP was reduced by an adjusted mean (SE) of 24.1 (1.9) mm Hg more in intervention patients than in controls (P < .001).
Even in patients who have diabetes and hypertension that are relatively well controlled, a pharmacist and nurse team-based intervention resulted in a clinically important improvement in BP. Trial Registration clinicaltrials.gov Identifier: NCT00374270.
Archives of internal medicine 12/2008; 168(21):2355-61. · 11.46 Impact Factor
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ABSTRACT: To describe the proportion of women who anticipate having breast-conserving surgery (BCS) versus modified radical mastectomy (MRM), the factors they considered when making treatment choices, the degree to which they perceived they had participated in and had control of the treatment decision, and to explore factors associated with type of planned surgery.
Prospective cohort study conducted among patients attending a tertiary care hospital in Alberta, Canada from 1992 to 1995. Participants had a first diagnosis of localized unilateral breast cancer, and were, in the opinions of their surgeons, candidates for either BCS or MRM.
Of 157 participants, 71.3% anticipated having BCS and 28.7% anticipated MRM. Referents perceived to play an important role in decision making included self, doctor, and significant other. The two top-ranked items perceived to have influenced treatment choice were doctor's advice and possibility of complete cure. Most women (60%) participated in treatment choice to the degree that they preferred, but only 13.6% received their preferred amount of information. The type of planned surgery was predicted by surgeon, contribution of doctor to choice of treatment, importance of breasts to sexuality, self-efficacy, and concerns about cancer recurrence from a multivariable logistic regression model.
Both patient and surgeon factors are important predictors of type of planned surgery. There is a gap between women's preferences and actual experiences with regard to information provided and patient participation in treatment choices, with women's desire for more information about their treatment being most prevalent.
Journal of Clinical Oncology 08/2006; 24(21):3367-73. · 18.37 Impact Factor
