Melinda L Irwin

Yale-New Haven Hospital, New Haven, Connecticut, United States

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Publications (113)555.46 Total impact

  • Melinda L Irwin
    Journal of clinical oncology : official journal of the American Society of Clinical Oncology. 06/2014;
  • Article: Response.
    CancerSpectrum Knowledge Environment 01/2014; · 14.07 Impact Factor
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    ABSTRACT: Background Ovarian cancer is often diagnosed at late stages and consequently the 5-year survival rate is only 44%. However, there is limited knowledge of the association of modifiable lifestyle factors, such as physical activity and obesity on mortality among women diagnosed with ovarian cancer. The purpose of our study was to prospectively investigate the association of (1) measured body mass index (BMI), and (2) self-reported physical activity with ovarian cancer-specific and all-cause mortality in postmenopausal women enrolled in the Women's Health Initiative (WHI). Methods Participants were 600 women diagnosed with primary ovarian cancer subsequent to enrollment in WHI. Exposure data, including measured height and weight and reported physical activity from recreation and walking, used in this analysis were ascertained at the baseline visit for the WHI. Cox proportional hazard regression was used to examine the associations between BMI, physical activity and mortality endpoints. Results Vigorous-intensity physical activity was associated with a 26% lower risk of ovarian cancer specific-mortality (HR = 0.74; 95% CI: 0.56–0.98) and a 24% lower risk of all-cause mortality (HR = 0.76; 95% CI: 0.58–0.98) compared to no vigorous-intensity physical activity. BMI was not associated with mortality. Conclusions Participating in vigorous-intensity physical activity, assessed prior to ovarian cancer diagnosis, appears to be associated with a lower risk of ovarian cancer mortality.
    Gynecologic Oncology 01/2014; 133(1):4–10. · 3.93 Impact Factor
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    ABSTRACT: The purpose of this study was to (a) examine demographic, psychosocial, and physiological predictors of exercise adherence in a yearlong exercise intervention and (b) describe the trajectory of adherence over time. Participants were 51 men and 49 women aged 40-75 years. The supervised- and home-based intervention consisted of 60 minutes/day, 6 days/week of moderate-to-vigorous intensity exercise. Three adherence measures were used: (a) minutes/week, (b) MET-hours/week, and (c) change in cardiopulmonary fitness (VO2max). Predictors of adherence were determined separately by sex using mixed models and multivariable regression. Participants performed 287 ± 98 minutes/week of moderate-to-vigorous activity with 71% adhering to at least 80% (288 minutes/week) of the prescription. Men adhered better than women (p<.001). Among women, adiposity-related variables were significantly related to poorer adherence on all three measures (p<.05). A less consistent pattern was observed among men but in follow-up analyses, adiposity was associated with fewer MET-hours/week of exercise. Social support, pain, and perceived benefits were predictive in some models. Men and non-obese women experienced peak adherence at 4-6 months, while obese women peaked during months 0-3. When provided with supervision and support, previously sedentary men and women can achieve and maintain high levels of aerobic activity.
    Journal of Physical Activity and Health 10/2013; · 1.95 Impact Factor
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    ABSTRACT: Bone mineral density (BMD) and lean mass (LM) may both decrease in breast cancer survivors, thereby increasing risk of falls and fractures. Research is needed to determine whether lean mass (LM) and fat mass (FM) independently relate to BMD in this patient group. The Health, Eating, Activity, and Lifestyle Study participants included 599 women, ages 29--87 years, diagnosed from 1995--1999 with stage 0-IIIA breast cancer, who underwent dual-energy X-ray absorptiometry scans approximately 6-months postdiagnosis. We calculated adjusted geometric means of total body BMD within quartiles (Q) of LM and FM. We also stratified LM-BMD associations by a fat mass index threshold that tracks with obesity (lower body fat: <=12.9 kg/m2; higher body fat: >12.9 kg/m2) and stratified FM-BMD associations by appendicular lean mass index level corresponding with sarcopenia (non-sarcopenic: >=5.45 kg/m2 and sarcopenic: <5.45 kg/m2). Higher LM (Q4 vs. Q1) was associated with higher total body BMD overall (1.12 g/cm2 vs. 1.07 g/cm2, p-trend < 0.0001), and among survivors with lower body fat (1.13 g/cm2 vs. 1.07 g/cm2, p-trend < 0.0001) and higher body fat (1.15 g/cm2 vs. 1.08 g/cm2, p-trend = 0.004). Higher FM (Q4 vs. Q1) was associated with higher total body BMD overall (1.12 g/cm2 vs. 1.07 g/cm2, p-trend < 0.0001) and among non-sarcopenic survivors (1.15 g/cm2 vs. 1.08 g/cm2, p < 0.0001), but the association was not significant among sarcopenic survivors (1.09 g/cm2 vs. 1.04 g/cm2, p-trend = 0.18). Among breast cancer survivors, higher LM and FM were independently related to higher total body BMD. Future exercise interventions to prevent bone loss among survivors should consider the potential relevance of increasing and preserving LM.
    BMC Cancer 10/2013; 13(1):497. · 3.33 Impact Factor
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    ABSTRACT: Higher self-reported physical activity is associated with lower breast cancer incidence and mortality. Objectively measured timed walking speed, predictive of longevity in older adults, has been associated with ambulatory physical activity in small studies but definitive assessment of the association is lacking. Participants were a subset of 14 719 postmenopausal women in the Women's Health Initiative study who, at entry, had 10 m, timed walking speed determined. After 12.4 years [mean (SD) (3.5)] follow-up, 762 invasive breast cancers were diagnosed in this group. In addition, 8162 of these women self-reported physical activity. Simple linear regression was used to examine the relationship between timed walking speed and self-reported physical activity. A Cox proportional hazard model was used to estimate age-adjusted hazard ratios and 95% confidence intervals for the association between timed walking speed and invasive breast cancer incidence. Although a linear regression model for self-reported physical activity [log metabolic equivalent task (MET) h/week] versus 10 m, timed walking speed had a statistically significant slope (coefficient=0.03, P<0.0001, correlation=0.20), the magnitude of the relationship was not clinically useful. Timed walking speed quintile was not associated with breast cancer incidence in age-adjusted or multivariant analyses (P for trend=0.60). Timed walking speed was not associated with self-reported physical activity in a clinically useful manner or with breast cancer incidence. Our findings do not support use of timed walking speed as an objective surrogate for self-reported physical activity.
    European journal of cancer prevention: the official journal of the European Cancer Prevention Organisation (ECP) 05/2013; · 2.21 Impact Factor
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    ABSTRACT: Background: Many cancer survivors experience declines in health-related quality of life (HRQOL) and increases in fatigue as a result of cancer and its treatment. Exercise is linked to improvements in these outcomes, but little is known about the role of sedentary behavior. In a large, ethnically-diverse cohort of breast cancer survivors, we examined the relationship between sedentary time, HRQOL, and fatigue, and examined if that relationship differed by recreational moderate-vigorous physical activity (MVPA) level. Methods: Participants were 710 women diagnosed with stage 0-IIIA breast cancer in the Health, Eating, Activity, and Lifestyle Study. Women completed questionnaires at approximately 30-months postdiagnosis (sedentary time; recreational MVPA) and 41-months postdiagnosis (HRQOL; fatigue). In multivariate models, we regressed these outcomes linearly on quartiles of daily sedentary time, and a variable jointly reflecting sedentary time quartiles and MVPA categories (0; >0 to <9; ≥9 MET-hrs/wk). Results: Sedentary time was not independently related to subscales or summary scores of HRQOL or fatigue. In addition, comparisons of women with high vs. low (Q4:Q1) sedentary time by MVPA level did not result in significant differences in HRQOL or fatigue. Conclusion: In this breast cancer survivor cohort, self-reported sedentary time was not associated with HRQOL or fatigue, 3.5 years postdiagnosis.
    Journal of Physical Activity and Health 03/2013; 10(3):350-8. · 1.95 Impact Factor
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    ABSTRACT: PURPOSE: Recognition of the complex, multidimensional relationship between excess adiposity and cancer control outcomes has motivated the scientific community to seek new research models and paradigms. METHODS: The National Cancer Institute developed an innovative concept to establish a center grant mechanism in nutrition, energetics, and physical activity, referred to as the Transdisciplinary Research on Energetics and Cancer (TREC) Initiative. This paper gives an overview of the 2011-2016 TREC Collaborative Network and the 15 research projects being conducted at the centers. RESULTS: Four academic institutions were awarded TREC center grants in 2011: Harvard University, University of California San Diego, University of Pennsylvania, and Washington University in St. Louis. The Fred Hutchinson Cancer Research Center is the Coordination Center. The TREC research portfolio includes three animal studies, three cohort studies, four randomized clinical trials, one cross-sectional study, and two modeling studies. Disciplines represented by TREC investigators include basic science, endocrinology, epidemiology, biostatistics, behavior, medicine, nutrition, physical activity, genetics, engineering, health economics, and computer science. Approximately 41,000 participants will be involved in these studies, including children, healthy adults, and breast and prostate cancer survivors. Outcomes include biomarkers of cancer risk, changes in weight and physical activity, persistent adverse treatment effects (e.g., lymphedema, urinary and sexual function), and breast and prostate cancer mortality. CONCLUSION: The NIH Science of Team Science group will evaluate the value added by this collaborative science. However, the most important outcome will be whether this transdisciplinary initiative improves the health of Americans at risk of cancer as well as cancer survivors.
    Cancer Causes and Control 02/2013; · 3.20 Impact Factor
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    ABSTRACT: PURPOSE: Sedentary time is a rapidly emerging independent risk factor for mortality in the general population, but its prognostic effect among cancer survivors is unknown. In a multiethnic, prospective cohort of breast cancer survivors, we hypothesized that television watching time would be independently associated with an increased risk of death from any cause. METHODS: The Health, Eating, Activity, and Lifestyle Study cohort included 687 women diagnosed with local or regional breast cancer. On average 30 (±4) months postdiagnosis, women completed self-report assessments on time spent sitting watching television/videos in a typical day in the previous year. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HR) and 95 % confidence intervals (CI) for death from any cause (n = 89) during the 7 years of follow-up. RESULTS: Television time (top tertile vs. bottom tertile) was positively related to risk of death (HR, 1.94; 95 % CI, 1.02, 3.66, p (trend) = 0.024), but the association was attenuated and not statistically significant after adjustment for aerobic moderate-vigorous intensity physical activity (HR, 1.70; 95 % CI, 0.89, 3.22, p (trend) = 0.14) and all covariates (HR, 1.39; 95 % CI, 0.69, 2.82, p (trend) = 0.48). CONCLUSION: In this first published investigation on this topic, we did not observe a statistically significant multivariate-adjusted association between television watching time and risk of death among women diagnosed with breast cancer. IMPLICATIONS FOR CANCER SURVIVORS: These results begin an evidence base on this topic that can be built upon to inform lifestyle recommendations for this expanding, aging population.
    Journal of Cancer Survivorship 02/2013; · 3.57 Impact Factor
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    ABSTRACT: Background Higher body mass index (BMI) and inactivity have been associated with a higher risk of developing endometrial cancer, but the impact on endometrial cancer survival is unclear.Methods Among incident endometrial cancer case subjects in the National Institutes of Health-AARP Diet and Health Study, we examined associations of prediagnosis BMI (n = 1400) and physical activity (n = 875) with overall and disease-specific 5- and 10-year mortality. Using Cox proportional hazards regression, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs), adjusting for tumor characteristics, treatment, and other risk factors. All statistical tests were two-sided.ResultsCompared with women with a BMI in the range of 18.5 to less than 25kg/m(2), the hazard ratios for 5-year all-cause mortality were 1.74 (95% CI = 1.13 to 2.66) for BMI in the range of 25 to less than 30kg/m(2), 1.84 (95% CI = 1.17 to 2.88) for BMI in the range of 30 to less than 35kg/m(2), and 2.35 (95% CI = 1.48 to 3.73) for BMI greater than or equal to 35kg/m(2) (P (trend) < .001). Higher BMI was also statistically significantly associated with poorer endometrial cancer-specific but not cardiovascular disease 5-year mortality. Hazard ratio estimates for 10-year all-cause and endometrial cancer-specific mortality as related to BMI were similar to 5-year hazard ratio estimates, whereas 10-year cardiovascular disease mortality became statistically significant (HR = 4.08; 95% CI = 1.56 to 10.71 comparing extreme BMI groups). More physical activity was related to lower all-cause 5-year mortality (HR = 0.57, 95% CI = 0.33 to 0.98 for >7 hours/week vs never/rarely), but the association was attenuated after adjustment for BMI (HR = 0.64, 95% CI = 0.37 to 1.12). No association was observed between physical activity and disease-specific mortality.Conclusions Our findings suggest that higher prediagnosis BMI increases risk of overall and disease-specific mortality among women diagnosed with endometrial cancer, whereas physical activity lowers risk. Intervention studies of the effect of these modifiable lifestyle factors on mortality are needed.
    CancerSpectrum Knowledge Environment 01/2013; · 14.07 Impact Factor
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    ABSTRACT: Objective. Breast cancer survivors are highly sedentary, overweight, or obese, which puts them at increased risk for comorbid chronic disease. We examined the prevalence of, and changes in, metabolic syndrome following 6 months of an aerobic exercise versus usual care intervention in a sample of sedentary postmenopausal breast cancer survivors. Design and Methods. 65 participants were randomized to an aerobic exercise intervention (EX) (n = 35) mean BMI 30.8 (±5.9) kg/m(2) or usual care (UC) (n = 30) mean BMI 29.4 (±7.4) kg/m(2). Metabolic syndrome prevalence was determined, as well as change in criteria and overall metabolic syndrome. Results. At baseline, 55.4% of total women met the criteria for metabolic syndrome. There was no statistically significant change in metabolic syndrome when comparing EX and UC. However, adhering to the exercise intervention (at least 120 mins/week of exercise) resulted in a significant (P = .009) decrease in metabolic syndrome z-score from baseline to 6 months (-0.76 ± 0.36) when compared to those who did not adhere (0.80 ± 0.42). Conclusions. Due to a higher prevalence of metabolic syndrome in breast cancer survivors, lifestyle interventions are needed to prevent chronic diseases associated with obesity. Increasing exercise adherence is a necessary target for further research in obese breast cancer survivors.
    International Journal of Endocrinology 01/2013; 2013:168797. · 2.52 Impact Factor
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    ABSTRACT: Physical activity is associated with improved breast cancer survival, but the underlying mechanisms, possibly including modification of the inflammatory state, are not well understood. We analyzed changes in interleukin (IL)-6, C-reactive protein (CRP), and tumor necrosis factor (TNF)-α in a randomized controlled trial of exercise in postmenopausal breast cancer survivors. Seventy-five women, recruited through the Yale-New Haven Hospital Tumor Registry, were randomized to either a 6-month aerobic exercise intervention or usual care. Correlations were calculated between baseline cytokines, adiposity and physical activity measures. Generalized linear models were used to assess the effect of exercise on IL-6, CRP, and TNF-α. At baseline, IL-6 and CRP were positively correlated with body fat and BMI and were inversely correlated with daily pedometer steps (p < .001). We found no significant effect of exercise on changes in inflammatory marker concentrations between women randomized to exercise versus usual care, though secondary analyses revealed a significant reduction in IL-6 among exercisers who reached 80% of the intervention goal compared to those who did not. Future studies should examine the effect of different types and doses of exercise and weight loss on inflammatory markers in large-scale trials of women diagnosed with breast cancer.
    Cancer Prevention Research 12/2012; · 4.89 Impact Factor
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    ABSTRACT: OBJECTIVE: While low physical activity and high body mass index (BMI) have been associated with higher endometrial cancer incidence, no previous studies have evaluated the association between physical activity and survival after endometrial cancer diagnosis, and studies on BMI and survival have not been performed in a prospective cohort. METHODS: We examined pre-diagnosis BMI and moderate- to vigorous-intensity physical activity in relation to overall and disease-specific survival among 983 postmenopausal women who were diagnosed with endometrial cancer in the Women's Health Initiative Observational Study and Clinical Trials. RESULTS: Over a median 5.2 (max 14.1) years from diagnosis to death or end of follow-up, 163 total deaths were observed, 66 of which were due to endometrial cancer. We observed a higher all-cause mortality hazard ratio (HR)=1.85 (95% CI 1.19-2.88) comparing women with a BMI ≥35kg/m(2) to women with BMI <25kg/m(2). For endometrial cancer-specific mortality the HR=2.23 (95% CI 1.09-4.54) comparing extreme BMI categories. To examine histologic subtypes we analyzed type I endometrial tumors separately and found a HR=1.20 (95% CI 1.07-1.35) associated with all-cause mortality for each 5-unit change in BMI. Moderate- to vigorous-intensity physical activity was not associated with all-cause or endometrial cancer-specific mortality. CONCLUSIONS: Pre-diagnosis BMI, but not physical activity, was associated with survival among women with endometrial cancer. Future studies should investigate mechanisms and timing of BMI onset to better understand the burden of disease attributable to BMI.
    Gynecologic Oncology 11/2012; · 3.93 Impact Factor
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    ABSTRACT: BACKGROUND AND PURPOSE: Previous studies have shown that physical inactivity and obesity are risk factors for the development of colorectal cancer. However, controversy exists regarding the influence of these factors on survival in colorectal cancer patients. We evaluated the impact of recreational physical activity and body mass index (BMI) before and after colorectal cancer diagnosis on disease-specific mortality and all-cause mortality. PATIENTS AND METHODS: This prospective cohort study included 1,339 women enrolled in the Women's Health Initiative study who were diagnosed with colorectal cancer subsequent to study enrollment. BMI and recreational physical activity were measured before cancer diagnosis at study entry (pre-diagnostic) and after diagnosis at study follow-up interviews (post-diagnostic). We used Cox regression to estimate the association between pre- and post-diagnostic exposures and survival after colorectal cancer diagnosis. RESULTS: Among women diagnosed with colorectal cancer, 265 (13 %) deaths occurred during a median study follow-up of 11.9 years, of which 171 (65 %) were attributed to colorectal cancer. Compared with women reporting no pre-diagnostic recreational physical activity, those reporting activity levels of ≥18 MET-h/week had significantly lower colorectal cancer-specific mortality (hazard ratio (HR) = 0.68; 95 % confidence interval (CI): 0.41-1.13) and all-cause mortality (HR = 0.63; 95 % CI: 0.42-0.96). Similar inverse associations were seen for post-diagnostic recreational physical activity. Neither pre- nor post-diagnostic BMI were associated with mortality after colorectal cancer diagnosis. CONCLUSION: Recreational physical activity before and after colorectal cancer diagnosis, but not BMI, is associated with more favorable survival.
    Cancer Causes and Control 10/2012; · 3.20 Impact Factor
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    ABSTRACT: PURPOSE: Animal and laboratory studies suggest that long-chain omega-3 (n-3) fatty acids, a type of polyunsaturated fat found in fatty fish, may protect against carcinogenesis, but human studies on dietary intake of polyunsaturated fats and fish with endometrial cancer risk show mixed results. METHODS: We evaluated the associations between endometrial cancer risk and intake of fatty acids and fish in a population-based sample of 556 incident cancer cases and 533 age-matched controls using multivariate unconditional logistic regression methods. RESULTS: Although total n-3 fatty acid intake was not associated with endometrial cancer risk, higher intakes of eicosapentaenoic (EPA 20:5) and docosahexaenoic (DHA 22:6) fatty acids were significantly associated with lower risks (OR = 0.57, 95 % CI: 0.39-0.84; OR = 0.64, 95 % CI: 0.44-0.94; respectively) comparing extreme quartiles. The ratio of n-3:n-6 fatty acids was inversely associated with risk only on a continuous scale (OR = 0.84, 95 % CI: 0.71-0.99), while total fish intake was not associated with risk. Fish oil supplement use was significantly associated with reduced risk of endometrial cancer: OR = 0.63 (95 % CI: 0.45-0.88). CONCLUSIONS: Our results suggest that dietary intake of the long-chain polyunsaturated fatty acids EPA and DHA in foods and supplements may have protective associations against the development of endometrial cancer.
    European Journal of Nutrition 08/2012; · 3.13 Impact Factor
  • H Arem, M L Irwin
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    ABSTRACT: Although it is known that obesity increases the risk of endometrial cancer and is linked to higher mortality rates in the general population, the association between obesity and mortality among endometrial cancer survivors is unclear. We performed a medline search using exploded Mesh keywords 'endometrial neoplasms/' and ('body mass index/' or 'obesity/') and ('survival analysis/' or 'mortality/' or (survivor* or survival*).mp.). We also inspected bibliographies of relevant papers to identify related publications. Our search criteria yielded 74 studies, 12 of which met inclusion criteria. Four of the included studies reported a statistically or marginally significant association between obesity and higher all cause mortality among endometrial cancer survivors after multivariate adjustment. The suggestive association between body mass index and higher all cause mortality among women with endometrial cancer was comparable to the magnitude of association reported in prospective studies of healthy women. Of the five studies that examined progression-free survival and the two studies reporting on disease-specific mortality, none reported an association with obesity. Future studies are needed to understand disease-specific mortality, the importance of obesity-onset timing and whether mechanisms of obesity-related mortality in this population of women differ from those of the general population.International Journal of Obesity advance online publication, 19 June 2012; doi:10.1038/ijo.2012.94.
    International journal of obesity (2005) 06/2012; · 5.22 Impact Factor
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    ABSTRACT: The risk of musculoskeletal injury with the introduction of moderate-to-vigorous exercise in sedentary adults is not well established. The purpose of this report is to examine the effect of a 12-month exercise intervention on musculoskeletal injury and bodily pain in predominately overweight, sedentary men (n = 102) and women (n = 100), ages 40 to 75 years. Participants were randomized to a moderate-to-vigorous aerobic exercise intervention (EX) (6 d/wk, 60 min/d, 60% to 85% max. heart rate) or usual lifestyle control (CON). Participants completed a self-report of musculoskeletal injury and body pain at baseline and 12-months. The number of individuals reporting an injury (CON; 28% vs. EX; 28%, P = .95) did not differ by group. The most commonly injured site was lower leg/ankle/foot. The most common causes of injury were sports/physical activity, home maintenance, or "other." In the control group, bodily pain increased over the 12 months compared with the exercise group (CON -7.9, EX -1.4, P = .05). Baseline demographics and volume of exercise were not associated with injury risk. Previously sedentary men and women randomized to a 12-month aerobic exercise intervention with a goal of 360 min/wk reported the same number of injuries as those in the control group and less bodily pain.
    Journal of Physical Activity and Health 02/2012; 9(2):198-207. · 1.95 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. · 4.89 Impact Factor
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    ABSTRACT: Identifying multi-level factors affecting physical activity (PA) levels among adolescents is essential to increasing activity to promote health within this population. This study examines the associations between PA and 11 independent factors among Manitoba high school students. The sample included 31,202 grade 9-12 students who completed the Manitoba Youth Health Survey. Associations between PA and independent factors were examined separately and through multivariate regression. Analyses were stratified by gender. Perception of athletic ability, school location, parental encouragement and number of active friends were strong predictors of activity for moderately active and active males and females. Grade was a significant predictor of PA for females at both levels of activity but only significant for males when comparing active to inactive students. Perception of schoolwork and means of transport were minimally associated with PA. Results highlight the importance of targeting multiple levels of influence to increase PA among youth. Programs should focus on older students, females and those who are inactive or moderately active. In addition, social modeling of PA and increasing self-efficacy around activity should be encouraged.
    International Journal of Public Health 09/2011; 57(2):315-24. · 1.99 Impact Factor
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    ABSTRACT: The purpose of this study was to determine the feasibility of using a tumor registry to recruit newly diagnosed survivors into a randomized controlled exercise trial and to discuss issues related to this recruitment strategy. A tumor registry-based rapid ascertainment system was used to recruit breast cancer survivors into a 6-month home-based, telephone-administered intervention of moderate-to-vigorous intensity exercise or a usual care group. 468 newly diagnosed cases were identified. Of these, 50 women (15.4% of those for which screening calls were made) were enrolled in the study. Women were randomized, on average, 11 weeks after diagnosis (SD = 4.8). Sixty-four percent were randomized before beginning treatment or within the first week of treatment. Time required to obtain physician consent was the primary determinant of diagnosis-to-randomization latency. Enrolled women were more likely than nonenrolled women to be non-Hispanic White and to have a college degree (P < .05). Tumor registries present a feasible means of recruiting breast cancer survivors before or early in adjuvant treatment. The success of recruiting survivors promptly after diagnosis is largely dependent on ability to rapidly obtain physician consent. Specific effort is needed to counteract self-selection effects that may lead to under-representation of minorities.
    Journal of Physical Activity and Health 09/2011; 8(7):955-63. · 1.95 Impact Factor

Publication Stats

6k Citations
555.46 Total Impact Points

Institutions

  • 1970–2014
    • Yale-New Haven Hospital
      • Department of Pathology
      New Haven, Connecticut, United States
  • 2011–2013
    • National Cancer Institute (USA)
      • • Applied Research Program (ARP)
      • • Nutritional Epidemiology
      Maryland, United States
    • National University (California)
      San Diego, California, United States
  • 2002–2013
    • Yale University
      • • School of Public Health
      • • Department of Chronic Disease Epidemiology
      • • School of Medicine
      New Haven, Connecticut, United States
    • United States Department of Agriculture
      • Agricultural Research Service (ARS)
      Washington, D. C., DC, United States
  • 2012
    • University of British Columbia - Vancouver
      • Department of Physical Therapy
      Vancouver, British Columbia, Canada
  • 2010–2012
    • Alberta Health Services
      • Department of Population Health Research
      Calgary, Alberta, Canada
  • 2001–2011
    • Fred Hutchinson Cancer Research Center
      • • Division of Public Health Sciences
      • • Cancer Prevention Program
      • • Prevention Center
      Seattle, WA, United States
  • 2009
    • National Institutes of Health
      • Branch of Outcomes Research
      Bethesda, MD, United States
  • 2007
    • The Ohio State University
      Columbus, Ohio, United States
    • Harvard Medical School
      • Department of Medicine
      Boston, MA, United States
  • 2005
    • Group Health Cooperative
      Seattle, Washington, United States
  • 2004
    • Brigham and Women's Hospital
      Boston, Massachusetts, United States
  • 1998–2001
    • University of South Carolina
      • Department of Exercise Science
      Columbia, SC, United States