Commercially Available Lifestyle Modification Program Decreases Inflammatory Biomarkers in BRCA1/2+ Breast Cancer Survivors

The goal of this randomized controlled trial was to examine the effect of a 12-month commercially available web-based lifestyle program (Precision Nutrition (PN), Inc©) on biomarkers of inflammation, compared to usual care among a national cohort of 35 BRCA1/2+ breast cancer survivors with surgically-induced early menopause. The PN program included access to a PN coach and completion of three daily activities: 1) exercises; 2) completing a nutritional/lifestyle habit, and 3) reading health related material. The exercise component was completed at home or at a local gym, and required 160 min/wk of exercise (3 days/week of progressive resistance exercise, 2 days/week of interval aerobic exercise, and 1 day/week of active recovery aerobic exercise). Blood draws, body composition measurements, and fitness capacity were measured at baseline and follow up. The cohort was middle-aged (46.1 ± 4.0 years of age), white, and well-educated. The intervention group (n = 19) was 74.8% adherent to the program (average of all components: fitness, behavioral, education). At baseline, higher insulin levels were associated with higher TNFα levels (r = 0.38, P = 0.04). Higher BMI as well as higher % body fat levels were significantly associated with higher levels of: insulin, IL6, and TNFα. There was a trend for association between lower fitness levels and higher insulin levels (r = −0.33, P = 0.07), and a significant association between lower fitness levels and higher IL6 and TNFα level. Following 12 months of the PN program we did not observe any significant between group differences for change in biomarker levels. Within the control group, IL8 levels decreased (P = 0.04). Within the intervention group, we observed decreased levels of insulin (P = 0.06), and TNFα (P = 0.02). In conclusion, we observed elevation of pro-inflammatory biomarkers in BRCA1/2+ breast cancer survivors with excess body fat and low fitness at baseline. Following the intervention, levels of pro-inflammatory cytokine TNFα were significantly reduced. BRCA1/2+ breast cancer survivors with prophylactic oophorectomy are still at enhanced risk for non-reproductive cancers. In this high risk population, identifying interventions such as PN to decrease chronic inflammation and subsequent DNA damage is critically important.

Abstract P6-12-06: Effect and moderators of exercise on fatigue in patients with breast cancer: Meta-analysis of individual patient data

Background - Fatigue is one of the most common and disabling complaints in patients with breast cancer and can effectively be reduced by physical exercise, with small to moderate effect sizes. To identify heterogeneity in responses to exercise and to further personalize exercise prescriptions, moderators of exercise effects on fatigue should be investigated. However, most randomized controlled trials (RCTs) are not adequately powered for such analyses. Therefore we conducted meta-analyses using the individual patient data of several exercise RCTs. The aim is to investigate the effect and moderators of physical exercise on cancer-related fatigue in patients with breast cancer.

Methods - Within the Predicting OptimaL cAncer RehabIlitation and Supportive care (POLARIS) consortium, principal investigators of 34 exercise RCTs worldwide have shared their individual patient data. Twenty-two of these RCTs included patients with breast cancer with a total sample size of 3,061. Different questionnaires to assess level of fatigue were used, which was acknowledged by using z-scores in the analysis. A one-step individual patient data meta-analysis, using a linear mixed-effect model adjusted for baseline fatigue, with a random intercept on study (to account for study clustering) was undertaken to investigate effect of exercise on fatigue. The result, a between-group difference in z-scores, corresponds to a Cohen's d effect size. An interaction term was included in the model to assess potential moderators including demographic (age, marital status, education), clinical (body mass index, presence of distant metastasis), intervention-related (intervention timing, delivery mode and duration), and exercise-related (exercise type, frequency, intensity, duration) characteristics.

Results – Exercise significantly reduced fatigue reported by women with breast cancer (β= -0.15, 95% CI -0.21;-0.09). This effect did not differ significantly between patients with different demographic and clinical characteristics (p-valuesinteraction >0.05). Also, neither timing (during or post-treatment) and duration of the intervention, nor exercise-related factors moderated intervention effects on fatigue. Supervised exercise had significantly larger effects on fatigue than unsupervised exercise (βdifference= -0.17, 95%CI -0.28;-0.05). Compared to the control group, supervised exercise significantly improved fatigue (β = -0.21, 95%CI = -0.28;-0.14), while unsupervised exercise did not (β = -0.04, 95%CI = -0.14;0.06).

Conclusion – Exercise significantly reduces fatigue in patients with breast cancer across subgroups formed on the basis of age, marital status, education level, body mass index, and presence of distant metastasis. The effect of exercise is significantly larger when performed under supervision. Hence, exercise, and preferably supervised exercise, represents a viable intervention for the prevention and treatment of fatigue among patients with breast cancer.

Citation Format: van Vulpen JK, Sweegers MG, Kalter J, Peeters PH, Courneya KS, Newton RU, Aaronson NK, Jacobsen PB, Steindorf K, Stuiver MM, Hayes S, Mesters I, Knoop H, Goedendorp M, Mutrie N, Thorsen L, Schmidt M, Sonke GS, Bohus M, James EL, Oldenburg HS, Velthuis MJ, Nollet F, Wenzel J, Wiskemann J, Galvão DA, Chinapaw MJ, Irwin ML, Griffith KA, van Weert E, Daley AJ, McConnachie A, Schulz K-H, Short CE, Plotnikoff RC, Potthoff K, van Beurden M, van Harten WH, Schmitz KH, Winters-Stone KM, Taaffe DR, van Mechelen W, Kersten M-J, Verdonck-de Leeuw IM, Brug J, Buffart LM, May AM. Effect and moderators of exercise on fatigue in patients with breast cancer: Meta-analysis of individual patient data [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-12-06.

Evaluation of a web-based weight loss intervention in overweight cancer survivors aged 50 years and younger

Purpose

Half of adult cancer survivors under age 50 years are obese. Excess body weight is associated with cancer recurrence, and effective weight loss interventions for younger cancer survivors are needed. Commercially available, online weight loss programmes are readily accessible, but few have been studied in this population. This study employed a single‐arm, pre‐post intervention (baseline‐6 month/baseline‐12 month comparisons) to preliminarily explore feasibility, efficacy and safety of an online, commercially available weight loss programme in breast (n = 30) and testicular (n = 16) cancer survivors under age 50 years.

Methods

The intervention included three daily components: exercise, nutritional/behavioural modification strategies and health lessons. Intention‐to‐treat and completers analyses were conducted. Feasibility was measured by participation (number of participants enrolled/number screened), retention (number of participants attending 6/12 month study visit/number of enrolled) and self‐reported adherence rates (average of mean percent adherence to each of the three intervention components). Efficacy was assessed by changes in initial weight (percent weight loss). Safety was assessed by adverse events.

Results

The mean participation rate was 42%. The retention rate was 59% at 6 and 49% at 12 months. The adherence rate for all participants (completers/dropouts/lost‐to‐follow‐up) was 50.1% at 6 and 44% at 12 months. Completers reported adherence rates of 68% at 12 months. Study participants lost 5.3% body weight at 12 months; completers lost 9%. Only three unexpected adverse events (unrelated to the intervention) were reported.

Conclusion

Clinically significant weight loss was observed, although retention rates were low. Findings generally support preliminary feasibility, efficacy and safety of this online weight loss programme, and future randomized control trials should be explored.

Abstract P3-08-02: Comparison of strategies for weight loss maintenance among rural breast cancer survivors: The rural women connecting for better health randomized controlled trial

Background: Breast cancer survivors who reside in rural areas represent one of the largest medically underserved populations of breast cancer survivors in the nation and have higher obesity prevalence compared to their urban counterparts. Given the evidence linking obesity with poor breast cancer prognosis, trials are needed to demonstrate ability to produce long-term weight loss maintenance in this hard-to-reach group. Group phone-based counseling via conference calls is a low-technology approach with excellent reach to rural areas. This treatment delivery approach capitalizes on the support benefits of in-person groups by allowing participants to interact in real time while also diminishing costs.

Methods: In this 2 phase trial, overweight and obese (BMI 27 to 45 kg/m2) rural breast cancer survivors (with initial stage 0-III disease) were randomized to one of two extended care interventions for weight loss maintenance (Phase 2) subsequent to an initial 6-month weekly group phone-based behavioral weight loss intervention (Phase 1). To be eligible for randomization for maintenance, participants must have lost ≥ 5% of their baseline weight during Phase 1. In Phase 2, participants were randomized to continued group phone-based counseling reduced in frequency to every other week during maintenance vs every other week mailed newsletters that followed the same content.

Results: 210 breast cancer survivors with a mean time since treatment of 3.5 years ± 2.4 years, mean age of 58.1 ± 9.9 years, and mean BMI of 33.9 ± 4.4 kg/m2 residing in a three state region of the rural Midwest were entered in the 6-month weight loss phase. Retention from baseline to 6 months (Phase 1) was 91%. Mean percent weight loss at 6 months for the total sample was 12.9% with 82% of enrolled participants ≥ 5% below baseline weight. 172 participants with a mean initial loss of 14.0% of baseline weight (12.8 ± 4.9 kg) were randomized to a maintenance intervention. Retention from 6 to 18 months (Phase 2) was 92%. Intent-to-treat analyses with imputation of missing data revealed participants in the group phone condition regained less weight (3.3 ± 4.8 kg) compared to participants in the newsletter condition (4.9 ± 4.8 kg; p = 0.03). Mean percent weight loss from baseline to 18 months did not significantly differ between the group phone condition (10.2 ± 7.5%) and the newsletter condition (9.2 ± 7.9%). However, at 18 months 75.3% of participants in the group phone condition remained ≥ 5% below baseline weight compared to 57.8% in the newsletter condition (p = .02).

Discussion: The initial group phone-based weight loss intervention exceeded typical weight losses reported in the literature with over 80% of enrolled participants achieving clinically meaningful weight loss. Continued group phone counseling was modestly better in sustaining weight loss at 18 months than a mailed newsletter. However, for both maintenance approaches, the majority of participants maintained a weight at 18 months that was 5% or more below baseline.

Citation Format: Befort CA, Klemp JR, Sullivan DK, Diaz FJ, Schmitz KH, Perri MG, Fabian CJ. Comparison of strategies for weight loss maintenance among rural breast cancer survivors: The rural women connecting for better health randomized controlled trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-08-02.

Weight Lifting and Physical Function among Breast Cancer Survivors: A Post Hoc Analysis of a Randomized Controlled Trial

Breast cancer survivors may experience deterioration of physical function. This is important because poor physical function may be associated with premature mortality, injurious falls, bone fracture, and disability. We conducted a post hoc analysis to explore the potential efficacy of slowly-progressive weight lifting to reduce the incidence of physical function deterioration among breast cancer survivors. Methods: Between October 2005 and August 2008, we conducted a single-blind, 12-month, randomized controlled trial of twice-weekly slowly-progressive weight lifting or standard care among 295 non-metastatic breast cancer survivors. In this post hoc analysis of data from the Physical Activity and Lymphedema Trial, we examined incident deterioration of physical function after 12-months, defined as a ≥10-point decline in the physical function subscale of the Medical Outcomes Short-Form 36-item (SF-36) questionnaire. We calculated the relative risk (RR) and 95% confidence interval (95% CI) using an unadjusted generalized linear model. Results: Study participants were 56 ± 9 years old (range 36–80). Median adherence to the weight lifting protocol was 81% over 12-months. As compared with the control group, the weight lifting group had greater improvements in upper- and lower-body strength at 12-months (both comparisons P < 0.001). The proportion of participants who experienced incident physical function deterioration after 12-months was 16.3% (24/147) in the control group and 8.1% (12/148) in the weight lifting group [RR: 0.49 (95% CI, 0.25–0.96); P = 0.04]. No serious or unexpected adverse events occurred that were related to weight lifting. Conclusion: Slowly-progressive weight lifting compared to standard care reduced the incidence of physical function deterioration among breast cancer survivors. These data are hypothesis generating. Future studies should directly compare the efficacy of weight lifting to other modalities of exercise, such as brisk walking, to appropriately inform the development of a confirmatory study designed to preserve physical function among breast cancer survivors.

P4-12-07: Outcomes of a Behavioral Weight Control Intervention among Rural Breast Cancer Survivors

Background: Obese breast cancer survivors have 1.5 to 2.5 fold increased risk of recurrence and death compared to their normal weight counterparts. Rural women, who comprise over 20% of the U.S. population of women, have significantly higher obesity rates as well as breast cancer treatment-related disparities. Thus, weight control intervention is a key strategy for secondary breast cancer prevention in this population. However, access can be challenging in the rural setting. Using conference call technology to deliver group-based intervention is well-suited for rural breast cancer survivors because it is easily accessible and provides real-time peer support. The purpose of this one-arm treatment study was to examine the impact of a 6-month group phone-based behavioral weight control intervention on anthropomorphic, diet, physical activity, and psychosocial/quality of life outcomes.

Methods: Eligible participants were post-menopausal breast cancer survivors (Stage I-IIIc, 3 months to 10 years since surgery, radiation, or chemotherapy, < 75 years of age, BMI 27–45 kg/m2) who resided in a rural area. The weight control intervention included a reduced calorie diet with 2 prepackaged meals and ≥5 fruit and vegetables servings daily, home-based physical activity gradually increased to 225 min/week of moderate intensity exercise, weekly self-monitoring logs, and weekly 60-minute group phone sessions that addressed behavioral modification and breast cancer survivorship topics. Group size ranged from 9 to 13 women. Measures included anthropometrics, two 24-hour dietary recall interviews, and questionnaires measuring physical activity, fatigue, depression, body image and sexuality, and self-efficacy for diet and physical activity behavior change. Results: Participants (n = 34) were 58.9 ± 7.8 years-old, 3.1 ± 1.6 years out from treatment, had a baseline BMI of 33.7 ± 4.4 kg/m2, and 63% were on anti-hormone therapy. Average sessions attendance among all participants, including 3 non-completers, was 90%. Ninety-one percent of participants (n = 31) attended > 75% of intervention sessions and completed post-treatment data collection visits. At 6 months, significant changes were observed for weight (−12.5 ± 5.8 kg, 13.9% of baseline weight), waist circumference (−9.4 ± 6.3 cm), daily energy intake (−349 ± 550 kcal/day), fruits and vegetables (+3.7 ± 4.3 servings/day), percent kcal from fat (−12.6 ± 8.6%), and physical activity (+1235 ± 832 kcal/week; all p's < .001). Significant improvements were also seen for Body Image subscales (Strength and Health, Social Barriers, Appearance and Sexuality), Depression, and Self-Efficacy for diet and physical activity behaviors (all p's < .05). Discussion: The intervention produced significant improvements in weight, diet, physical activity, and quality of life outcomes that compare favorably to the literature. The group phone-based treatment delivery approach appears feasible and effective for weight control intervention among obese rural breast cancer survivors.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-12-07.

Exercise lowers estrogen and progesterone levels in premenopausal women at high risk of breast cancer

Experimental and clinical data support a role for estrogens in the development and growth of breast cancer, and lowered estrogen exposure reduces breast cancer recurrence and new diagnoses in high-risk women. There is varied evidence that increased physical activity is associated with breast cancer risk reduction in both pre- and postmenopausal women, perhaps via lowered estrogen levels. The purpose of this study was to assess whether exercise intervention in premenopausal women at increased breast cancer risk reduces estrogen or progesterone levels. Seven healthy premenopausal women at high risk for breast cancer completed a seven-menstrual-cycle study. The study began with two preintervention cycles of baseline measurement of hormone levels via daily first-morning urine collection, allowing calculation of average area under the curve (AUC) hormone exposure across the menstrual cycle. Participants then began five cycles of exercise training to a maintenance level of 300 min per week at 80-85% of maximal aerobic capacity. During the last two exercise cycles, urinary estradiol and progesterone levels were again measured daily. Total estrogen exposure declined by 18.9% and total progesterone exposure by 23.7%. The declines were mostly due to decreased luteal phase levels, although menstrual cycle and luteal phase lengths were unchanged. The study demonstrated the feasibility of daily urine samples and AUC measurement to assess hormone exposure in experimental studies of the impact of interventions on ovarian hormones. The results suggest value in exercise interventions to reduce hormone levels in high-risk women with few side effects and the potential for incremental benefits to surgical or pharmacologic interventions.

Abstract ES9-3: Balancing Risks of Deconditioning vs. Weight-Lifting for Breast Cancer Survivors

Background: Clinical guidelines for breast cancer survivors with and at-risk for lymphedema have advised against upper body exercise, preventing them from obtaining established health benefits of weight-lifting. The primary hypotheses of the Physical Activity and Lymphedema Trial were that lymphedema onset and worsening would not differ after a one-year weightlifting intervention compared to no exercise among survivors at risk for and with breast cancer-related lymphedema.

Methods: We performed a randomized controlled trial of a twice-weekly progressive weight-lifting intervention involving 141 breast cancer survivors with stable arm lymphedema at study entry and 154 survivors at-risk for lymphedema at study entry. Treatment group participants were provided a gym membership and 13 weeks of supervised instruction; the remaining nine months were unsupervised. Control group participants were provided the intervention after study completion. The primary outcome was the change in arm swelling at one year, as measured by water volumetry of the affected and unaffected arms. Secondary outcomes included the clinician defined incidence of onset and exacerbations of lymphedema, lymphedema symptoms, and muscle strength. Participants with lymphedema were required to wear a well-fitted compression garment while weight-lifting.

Results: Among the women who entered the study with lymphedema, the proportion who experienced a 5% or greater increase in arm swelling (interlimb difference) was similar in the treatment and control groups (11% versus 12%; cumulative incidence ratio [95% confidence interval], 1.00 (0.88 to 1.13) As compared with the control group, the women in the intervention group with lymphedema had greater improvements in self-reported lymphedema symptom severity (p=0.03), and a lower incidence of lymphedema exacerbations as assessed by a certified lymphedema specialist (14% versus 29% in the control group, p= 0.04). Among the women who entered the study without lymphedema, more control than treatment group women experienced lymphedema onset defined by 5% increase in interlimb difference (17 versus 11%, p = 0.35). Among higher risk women (5+ lymph nodes removed), this comparison was statistically significant (22 versus 7%, p=0.04). Clinician-defined BCRL onset occurred in 1 treatment and 3 control group women (p=0.62).

Conclusions: Slowly progressive weight-lifting had no significant impact on arm swelling among breast cancer survivors with lymphedema, and resulted in a reduced incidence of lymphedema flares and improvement in symptoms. In breast cancer survivors at risk for lymphedema, a program of slowly progressive weight-lifting, compared with no intervention, did not result in increased incidence of lymphedema. In secondary analyses, women with 5+ nodes removed who did weight-lifting were less likely to experience increases in arm swelling.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr ES9-3.

Impact of lymphedema and arm symptoms on quality of life in breast cancer survivors

Lymphedema is one of many arm problems reported by breast cancer survivors. Understanding the impact of lymphedema on quality of life requires consideration that arm symptoms may occur with or without lymphedema. It was hypothesized that specific arm symptoms and pain, related or unrelated to lymphedema, would be more associated with quality of life outcomes than arm swelling. The relation of arm swelling and of arm symptoms and associated severity with a range of quality of life outcomes following breast cancer treatment was assessed in a diverse sample of 295 women, 141 of whom had a clinical diagnosis of lymphedema. Arm swelling (as defined by interlimb volume or circumference differences) and lymphedema severity (defined by Common Toxicity Criteria) were less correlated with quality of life than total number of arm symptoms and specific individual symptoms. Pain in the affected arm correlated with poor quality of life outcomes, regardless of arm swelling. When evaluating the impact of lymphedema on quality of life, arm swelling may not be as important as the total number and specific types of arm symptoms present, as these may be more informative about quality of life outcomes in survivors of breast cancer with and without lymphedema.

Changes in inflammatory biomarkers following one-year of moderate resistance training in overweight women

BACKGROUND

Overweight individuals commonly demonstrate elevated levels of inflammatory and cell adhesion molecules. Elevated levels of inflammation and adhesion have been implicated in the pathogenesis of cardiovascular disease. Aerobic exercise has been shown to be effective in altering specific biomarkers of inflammation and cell adhesion; however, little is known regarding the effects of resistance training (RT) on these biomarkers. This study examined the effects of 1 year of moderate-intensity RT on biomarkers of inflammation and adhesion in healthy, overweight women.

METHODS AND RESULTS

Participants included 28 (12 control, 16 RT) overweight (body mass index>or=25 kg/m2) women, aged 25-44 years, studied before and after 1 year of RT. C-reactive protein (CRP), interleukin-6 (IL-6), adiponectin, intracellular adhesion molecule-1, vascular cell adhesion molecule-1 and E-selectin were measured by standard enzyme-linked immunosorbent assays. Body composition, blood pressure, fasting blood lipids, glucose and insulin also were assessed. There were no significant changes in blood pressure, fasting blood lipids, glucose or insulin levels in either group after 1 year. There was also no change in body mass or fat mass in either group; however, there was a significant increase in lean body mass (P<0.05) in the RT group. Both CRP (P<0.01) and adiponectin (P<0.01) demonstrated significant improvements in the RT group, with no change in IL-6. Conversely, there were no associated changes in the biomarkers of cell adhesion in either group.

CONCLUSIONS

This study demonstrates that moderate-intensity RT significantly results in modest improvements of inflammatory markers without affecting cell adhesion molecules in overweight women.

Comparison of the validity of anthropometric and bioelectric impedance equations to assess body composition in adolescent girls

OBJECTIVE: The purpose of this study was to examine the validity of two anthropometric and four bioelectric impedance (BIA) equations to estimate body composition from dual-energy x-ray absorptiometry (DXA) in adolescent girls of various ethnicities. The rationale for this study was to develop a prediction equation for percent body fat in a multi-ethnic, representative sample of sixth to eighth grade girls. DESIGN: One-hundred and sixty-six girls (51 African-American, 45 non-Black Hispanic, 55 non-Hispanic Caucasian, 15 multi-ethnic) participated. Estimates of percent fat and fat-free mass (FFM) from six published BIA and anthropometric equations and the equation developed from this study were compared to body composition determined from DXA. An RJL Systems analyzer was used to measure BIA. Anthropometry included body weight, height, and triceps and calf skinfolds. RESULTS: Average (± SD) age, size and body composition was as follows: age, 12.1±1.2 yrs, body mass 52.7±15.9 kg, height, 154.6±8.1 cm; DXA percent fat, 27.9±10.4; fat mass (FM), 15.6±10.2 kg; and fat free mass (FFM) 35.7±6.8 kg. No ethnic differences were found in the relationships between estimated and DXA measured body composition, with the exception of the skinfold equation. The six equations explained on average 82% of the variance in percent fat, 94% of the variance in fat mass, and 88% in fat free mass. Bland-Altman analysis indicated that none of the equations performed satisfactorily in our sample. CONCLUSIONS: The BIA and anthropometric equations were significantly related to DXA body composition parameters, however none met the criteria for cross-validation.

Assessment of coronary heart disease risk in testicular cancer survivors

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Background: Testicular cancer survivors (TCS) who receive cisplatin-based chemotherapy (CBCT) are reported to have an increased risk of coronary heart disease (CHD) compared to chemo-naive TCS (J Clin Oncol 21:1513–1523, 2003). We hypothesized that TCS treated with CBCT would demonstrate abnormal objective measures of future CHD risk compared to chemo-naive TCS. Methods: TCS ≥ 2 years from diagnosis underwent evaluation using established objective measures predictive of future CHD risk: body mass index (BMI), Framingham relative risk (RR), flow-mediated endothelium-dependent vasodilation of the brachial artery (FMD), carotid artery intima-media thickness (IMT), serum intercellular adhesion molecule-1 (ICAM-1), and high sensitivity C-reactive protein (hs-CRP). Data were analyzed using parametric and non-parametric statistics as appropriate. Results: 30 TCS who received CBCT and 20 chemo-naive TCS were recruited. The mean age and time from diagnosis were similar between the 2 groups. Both groups demonstrated elevated BMI, increased Framingham RR, and impaired FMD, consistent with an increased risk of CHD. However, there were no statistically significant differences in these measures between the two groups. Carotid IMT, ICAM-1, and hs-CRP were not significantly abnormal and these measures also did not differ between the two groups. Conclusions: TCS demonstrate abnormal objective measures of CHD risk in both CBCT-treated and chemo-naive groups. These data suggest that behavioral interventions to modify CHD risk should target all TCS independent of chemotherapy status. All values reported are mean ± standard deviation

[Table: see text]

No significant financial relationships to disclose.

Strength training for obesity prevention in midlife women

OBJECTIVE

The primary goal of this study was to assess whether increases in fat-free mass (FFM) and decreases in total and percentage fat mass from 15 weeks of twice weekly supervised strength training would be maintained over 6 months of unsupervised exercise in a randomized controlled trial.

DESIGN

In all, 60 women aged 30-50 y, body mass index between 20 and 35 kg/m(2), were randomized to control or treatment groups. The treatment group performed twice-weekly supervised strength training followed by 6 months of unsupervised training. Measurements at baseline, 15, and 39 weeks included body weight and body composition by dual-energy X-ray absorptiometry. Repeated measures regression was used to assess between-group differences for changes over time.

RESULTS

Almost 90% of prescribed exercise sessions were completed. The body composition treatment effects over 15 weeks were largely maintained over 6 months of unsupervised exercise. Over the total 39 weeks of strength training, the treatment group gained +0.89 kg more in FFM, lost -0.98 kg more in fat mass, and lost -1.63% more in percent body fat when compared to the control group. P-values for these between-group differences in 39-week changes were 0.009, 0.06, and 0.006, respectively. Strength training did not result in any significant weight loss or waist circumference attenuation. Adjustment for changes in energy intake and physical activity did not alter these results.

CONCLUSIONS

Twice-weekly strength training is behaviorally feasible for busy midlife women and the favorable body composition changes resulting from supervised strength training can be maintained over time. These findings lay the groundwork for determining the long-term health benefits of this behaviorally feasible exercise prescription, potentially including prevention of age-associated fat gains.

Association of physical activity with insulin sensitivity in children

BACKGROUND

Physical activity (PA) has been shown to improve insulin resistance and other cardiovascular disease risk factors in normal and diabetic adults and in obese youth, but not in non-diabetic, normal-weight children.

METHODS

Data from 357 non-diabetic children (10-16 y) were used to examine cross-sectional associations with PA. Insulin sensitivity was assessed with a euglycemic hyperinsulinemic clamp and expressed as M(ffm) (glucose utilization/kg of fat-free mass/min).

RESULTS

Correlations were adjusted for age, sex, race and Tanner stage. PA was significantly correlated with fasting insulin and insulin sensitivity (r=-0.12, P=0.03 and r=0.13, P=0.001, respectively), more strongly in children with above-median systolic blood pressure (r=-0.17, P=0.03 and r=0.35, P=0.0001, respectively). Further adjustment for body mass index, body fat percentage, waist circumference or lipids did not alter these observations.

CONCLUSIONS

Physical activity is correlated with lower fasting insulin and greater insulin sensitivity in childhood. These results are consistent with the hypothesis that increasing physical activity among youth may reduce the incidence of type 2 diabetes in children and adolescents.

Arterial distensibility and physical activity in the ARIC study

PURPOSE

Arterial distensibility decreases with age. This decrease may be associated with the initiation and/or progression of hypertension and atherosclerosis and may be attenuated by positive lifestyle habits, including habitual physical activity. We tested the hypothesis that self-reported sport, leisure, and work physical activity is associated with greater arterial distensibility (i.e., carotid artery pulsatile diameter changes).

METHODS

The Atherosclerosis Risk in Communities (ARIC) study assessed left common carotid arterial diameters and intimal-medial wall thickness (IMT) using B-mode ultrasound techniques, in 10,644 African-American and white men and women aged 45-64 yr and free of cardiovascular disease.

RESULTS

Work activity, but not sports or leisure activity, was weakly associated with greater arterial distensibility in an ANCOVA model adjusted for blood pressure and other covariates (diastolic arterial diameter, pulse pressure, pulse pressure squared, age, race, sex, smoking, dietary fat intake, height, education, and clinical center) (P for linear trend = 0.03). Vigorous sports activity was weakly positively associated with arterial distensibility (arterial diameter change (mean +/- SE in mm) 0.42 +/- 0.004 vs 0.41 +/- 0.002 for the 12.7% of participants reporting any vs no vigorous activity, P = 0.02), and this association was not attenuated by adjustment for IMT, body mass index, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, or diabetes. Repeated analyses with traditional arterial stiffness indices showed similar findings for vigorous but not work activity.

CONCLUSION

In contrast to several smaller studies, these findings do not support the hypothesis that habitual physical activity has a strong, consistent positive effect on arterial distensibility.

Independent and interactive effects of apolipoprotein E phenotype and cardiorespiratory fitness on plasma lipids

PURPOSE

To examine whether the association Apolipoprotein E (Apo E) phenotype with plasma lipids is influenced by physical fitness level. Also, to explore the interactive and independent relative contributions of Apo E phenotype, fitness (or physical activity), and other modifiable factors to variation in plasma low density lipoprotein (LDL-C) and high density lipoprotein (HDL-C) levels at baseline and over a seven-year follow-up.

METHODS

Physical fitness (duration of a graded treadmill test), Apo E phenotype, plasma LDL-C and HDL-C, and covariates were measured at baseline and seven years later in a bi-racial cohort of young adults, aged 18-30 years at baseline in 1985-86, from the Coronary Artery Risk Development In Young Adults (CARDIA) study.

RESULTS

Fitness did not influence the associations of Apo E and LDL-C or HDL-C. The independent effects of several modifiable variables (changes in Keys' score, smoking, oral contraceptive use, education, body weight, alcohol intake, and fitness), when combined, contributed considerably more than Apo E to the variance in LDL-C changes (6.74% or 8.71% for combined modifiable variables vs. 1.27% or 0.90% for ApoE, in women or men, respectively) and HDL-C changes (13.11% or 12.66% for combined modifiable variables vs. 0.12% or 0.02% for ApoE, in women or men, respectively). The pattern of findings was similar when self-reported physical activity was substituted for fitness.

CONCLUSIONS

Changes in modifiable factors, including fitness, may be stronger correlates of changes in LDL-C and HDL-C over time than the immutable factor, Apo E phenotype.

Physical activity and body weight: associations over ten years in the CARDIA study. Coronary Artery Risk Development in Young Adults

BACKGROUND

Hypothesis 1--sustained changes in physical activity are inversely related to changes in body weight. Hypothesis 2-those who attenuate weight gain because of a temporary increase in physical activity (PA) may maintain a lower body weight over time.

METHODS

Data were from the Coronary Artery Risk Development in Young Adults (CARDIA) Study, a cohort of black and white men and women, aged 18-30y at baseline, who attended up to five examinations over a 10y period (n=5,115 at baseline). Longitudinal associations between physical activity and body weight changes were assessed, adjusting for secular trend, age, clinic site, education, smoking, alcohol intake, parity, percentage energy intake from fat, and changes in these variables over time. For hypothesis 1, concurrent associations of physical activity and body weight changes were examined. For hypothesis 2, we explored whether weight gain attenuation associated with increased PA during the initial 2-3 y of follow-up was sustained over 5 y. The study 2 analyses were conducted with three separate 5y intervals: baseline to year 5 (n= 3,641), years 2-7 (n= 3,160), and years 5-10 (n= 2,617).

RESULTS

Hypothesis 1 -change in physical activity was inversely associated with change in body weight within all four race and sex sub-groups (P<0.005). The predicted weight change associated with change in physical activity was four to five times larger in participants who were overweight compared with those who were not were overweight at baseline. Hypothesis 2-an increase in physical activity during 2-3 y of follow-up was associated with an attenuation of weight gain that was sustained through 5y of follow-up whether or not the physical activity increase was maintained during the later years. This finding persisted whether the starting point for the 5y follow-up was year 2, year 5 or baseline (women only). Comparing participants who increased physical activity with those who decreased physical activity in the first 2-3 y of follow-up (eg by at least 2 h per week of stationary cycling for at least 6 months per year), the mean 5y weight gain attenuation ranged from 0.8 to 2.8 kg.

CONCLUSIONS

The results of these analyses support the need for public health messages for promoting increased physical activity for weight maintenance and attenuation of age-related weight gain, especially for higher weight sub-populations.

Compendium of physical activities: an update of activity codes and MET intensities

We provide an updated version of the Compendium of Physical Activities, a coding scheme that classifies specific physical activity (PA) by rate of energy expenditure. It was developed to enhance the comparability of results across studies using self-reports of PA. The Compendium coding scheme links a five-digit code that describes physical activities by major headings (e.g., occupation, transportation, etc.) and specific activities within each major heading with its intensity, defined as the ratio of work metabolic rate to a standard resting metabolic rate (MET). Energy expenditure in MET-minutes, MET-hours, kcal, or kcal per kilogram body weight can be estimated for specific activities by type or MET intensity. Additions to the Compendium were obtained from studies describing daily PA patterns of adults and studies measuring the energy cost of specific physical activities in field settings. The updated version includes two new major headings of volunteer and religious activities, extends the number of specific activities from 477 to 605, and provides updated MET intensity levels for selected activities.

Effects of recombinant human tumor necrosis factor on rodent gliomas and normal brain

In a study examining the possible therapeutic effects of recombinant human tumor necrosis factor-alpha (rHuTNF-alpha) on malignant gliomas without expression of tumor necrosis factor (TNF)-receptors, RG-2 glioma cells were tested in vitro as well as in a rat experimental glioma model. A growth inhibition assay revealed no inhibiting effect in vitro up to a concentration of 20 micrograms/ml rHuTNF-alpha. Receptor-binding studies showed that RG-2 cells did not present specific receptors for rHuTNF-alpha. The pharmacokinetics of rHuTNF-alpha after intravenous injection were studied with respect to serum, tissue, and brain tumor concentrations and showed increased glioma concentrations of (mean +/- standard error of the mean) 0.47 +/- 0.18 ng TNF/mg brain compared to 0.15 +/- 0.05 ng TNF/mg brain in the normal contralateral hemisphere. No therapeutic effect on solid RG-2 gliomas could be observed after stereotactic injection of 7.3 micrograms rHuTNF/10 microliter buffer solution into the tumor in 10 animals. Immunohistochemical studies after stereotactic injection of rHuTNF-alpha showed total disappearance of the substance after 24 hours without internalization into tumor cells. Stereotactic injection of 7.3 micrograms rHuTNF 10 microliters into normal brain resulted in marked inflammatory response around the injection track, including microvascular thrombosis. These results demonstrate that rHuTNF has neither direct nor indirect cytotoxic activity on RG-2 glioma cells. Furthermore, before clinical use of rHuTNF-alpha in malignant gliomas, the authors suggest that receptor studies be done in each patient. In receptor-positive patients undergoing treatment with rHuTNF-alpha, precautions should be taken to prevent local encephalitic reactions.