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Background: Higher body mass index (BMI) is associated with incident colorectal cancer but not consistently with colorectal cancer survival. Whether weight gain or loss is associated with colorectal cancer survival is largely unknown. Methods: We identified 2,781 patients from Kaiser Permanente Northern California diagnosed with stages I–III colorectal cancer between 2006 and 2011 with weight and height measurements within 3 months of diagnosis and approximately 18 months after diagnosis. We evaluated associations between weight change and colorectal cancer–specific and overall mortality, adjusted for sociodemographics, disease severity, and treatment. Results: After completion of treatment and recovery from stage I–III colorectal cancer, loss of at least 10% of baseline weight was associated with significantly worse colorectal cancer–specific mortality (HR 3.20; 95% confidence interval [CI], 2.33–4.39; Ptrend < 0.0001) and overall mortality (HR 3.27; 95% CI, 2.56–4.18; Ptrend < 0.0001). For every 5% loss of baseline weight, there was a 41% increased risk of colorectal cancer–specific mortality (95% CI, 29%–56%). Weight gain was not significantly associated with colorectal cancer–specific mortality (Ptrend = 0.54) or overall mortality (Ptrend = 0.27). The associations were largely unchanged after restricting analyses to exclude patients who died within 6 months and 12 months of the second weight measurement. No significant interactions were demonstrated for weight loss or gain by gender, stage, primary tumor location, or baseline BMI. Conclusions: Weight loss after diagnosis was associated with worse colorectal cancer–specific mortality and overall mortality. Reverse causation does not appear to explain our findings. Impact: Understanding mechanistic underpinnings for the association of weight to worse mortality is important to improving patient outcomes. Cancer Epidemiol Biomarkers Prev; 26(1); 30–37. ©2016 AACR. See all the articles in this CEBP Focus section, “The Obesity Paradox in Cancer: Evidence and New Directions.”

There is an increasing impetus to transform the U.S transportation sector and transition away from the uncertainties of oil supply. One of the most viable current solutions is the adoption of electric vehicles (EVs). These vehicles allow for a transportation system that would be flexible in its fuel demands. However, utilities may need to address questions such as distribution constraints, electricity tariffs and incentives and public charging locations before large scale electric vehicle adoption can be realized. In this study, the effect of electric vehicles on households in Indianapolis is examined. A four-step traffic flow model is used to characterize the usage characteristics of vehicles in the Indianapolis metropolitan area. This data is then used to simulate EV usage patterns which can be used to determine household electricity usage characteristics. These results are differentiated by the zones with which the households are associated. Economic costs are then calculated for the individual households. Finally, possible public charging locations are examined.

Microgeneration using solar photovoltaic (PV) systems is one of the fastest growing applications of solar energy in the United States. Its success has been partly fueled by the availability of net metering by electric utilities. However, with increasing solar PV penetration, the availability of net metering is likely to be capped. Households would then need to rely on distributed storage to capture the full benefits of their installed PV systems. Although studies of these storage systems to assess their benefits to the individual household have been examined in literature, the systemwide benefits have yet to be fully examined. In this study, the utility level benefits of distributed PV systems coupled with electricity storage are quantified. The goal is to provide an estimate of these benefits so that these savings can potentially be translated into incentives to drive more PV investment. An agent-based residential electricity demand model is combined with a stochastic programming unit commitment ...

To determine the prevalence of low skeletal muscle mass in patients undergoing transcatheter aortic valve replacement (TAVR) and whether skeletal muscle mass measured from preoperative computed tomography (CT) images provides value in predicting postoperative length of stay (LOS).There are limited data on the use of body composition as a frailty measure in TAVR patients and no studies have determined if this measure predicts LOS.We studied 104 consecutive patients who underwent TAVR at Tallahassee Memorial Hospital from 2012 to 2016. Patient demographics, standard frailty measures (hand grip, albumin, and 5-m walk test), clinical comorbidities, echocardiographic data, and Valve Academic Research Consortium II major complications were recorded prospectively. Skeletal muscle index (SMI) [skeletal muscle mass cross-sectional area at L3/heightSarcopenia was prevalent in men (83%) and women (56%). Patients who suffered from a major complication had significantly longer length of stay (13 vs 4.6days, P.0001). Skeletal muscle index correlated with age, sex, body mass index, handgrip strength, and previous coronary artery bypass graft surgery, but not major complications. A multivariate model including all univariate predictors of LOS showed SMI, major complications, transapical access, atrial fibrillation, and chronic obstructive pulmonary syndrome as independent predictors of LOS. For every 14-cmSkeletal muscle index, a measure of sarcopenia readily determined from pre-TAVR CT scans, independently predicts TAVR LOS better than standard frailty testing. Further evaluation of SMI as a frailty measure after TAVR and other cardiovascular procedures is warranted.

Systemic inflammation and sarcopenia are easily evaluated, predict mortality in many cancers, and are potentially modifiable. The combination of inflammation and sarcopenia may be able to identify patients with early-stage colorectal cancer (CRC) with poor prognosis.To examine associations of prediagnostic systemic inflammation with at-diagnosis sarcopenia, and determine whether these factors interact to predict CRC survival, adjusting for age, ethnicity, sex, body mass index, stage, and cancer site.A prospective cohort of 2470 Kaiser Permanente patients with stage I to III CRC diagnosed from 2006 through 2011.Our primary measure of inflammation was the neutrophil to lymphocyte ratio (NLR). We averaged NLR in the 24 months before diagnosis (mean count = 3 measures; mean time before diagnosis = 7 mo). The reference group was NLR of less than 3, indicating low or no inflammation.Using computed tomography scans, we calculated skeletal muscle index (muscle area at the third lumbar vertebra divided by squared height). Sarcopenia was defined as less than 52 cm2/m2 and less than 38 cm2/m2 for normal or overweight men and women, respectively, and less than 54 cm2/m2 and less than 47 cm2/m2 for obese men and women, respectively. The main outcome was death (overall or CRC related).Among 2470 patients, 1219 (49%) were female; mean (SD) age was 63 (12) years. An NLR of 3 or greater and sarcopenia were common (1133 [46%] and 1078 [44%], respectively). Over a median of 6 years of follow-up, we observed 656 deaths, 357 from CRC. Increasing NLR was associated with sarcopenia in a dose-response manner (compared with NLR 3, odds ratio, 1.35; 95% CI, 1.10-1.67 for NLR 3 to5; 1.47; 95% CI, 1.16-1.85 for NLR ≥ 5; P for trend .001). An NLR of 3 or greater and sarcopenia independently predicted overall (hazard ratio [HR], 1.64; 95% CI, 1.40-1.91 and HR, 1.28; 95% CI, 1.10-1.53, respectively) and CRC-related death (HR, 1.71; 95% CI, 1.39-2.12 and HR, 1.42; 95% CI, 1.13-1.78, respectively). Patients with both sarcopenia and NLR of 3 or greater (vs neither) had double the risk of death, overall (HR, 2.12; 95% CI, 1.70-2.65) and CRC related (HR, 2.43; 95% CI, 1.79-3.29).Prediagnosis inflammation was associated with at-diagnosis sarcopenia. Sarcopenia combined with inflammation nearly doubled risk of death, suggesting that these commonly collected biomarkers could enhance prognostication. A better understanding of how the host inflammatory/immune response influences changes in skeletal muscle may open new therapeutic avenues to improve cancer outcomes.

Importance: A higher neutrophil-to-lymphocyte ratio (NLR, indicating systemic inflammation), and sarcopenia (reduced skeletal muscle mass) predict morbidity/mortality in a variety of cancers, but no prior research examines associations of pre-diagnostic NLR with at-diagnosis sarcopenia, nor whether NLR and sarcopenia combined identify early-stage patients with poor prognosis in colorectal cancer (CRC).Objective: To evaluate the association between pre-diagnosis NLR and at-diagnosis sarcopenia and of their combination with CRC survival, controlling for age, ethnicity, sex, body mass index, stage, and cancer site. Design, Setting, and Participants: This observational cohort with prospectively-collected data included 2470 patients diagnosed with stage I-III CRC at Kaiser Permanente from 2006-2011 with computed tomography (CT) scans from clinical care (mean days pre-diagnosis=6). Exposures: Systemic inflammation measured via average NLR in the 24 months pre-diagnosis (mean count=3 measures, mean months pre-diagnosis=7). The reference value was NLR below 3, indicating low/no inflammation. Main Outcomes and Measures: Sarcopenia, defined by published cutoffs for skeletal muscle index (CT muscle area in cm2 at the third lumbar vertebra divided by squared height in m2; below 52-cm2/m2 and 38-cm2/m2 for normal/overweight men and women, respectively, and below 54-cm2/m2 and 47-cm2/m2 for obese men and women, respectively), and incident death (overall or CRC-related). Results: Average age was 63 years; half of patients were female. NLR above 3 and sarcopenia were common (46% and 44%, respectively). Over a median of 6 years, we observed 656 deaths, 357 from CRC. Elevated NLR was associated with sarcopenia in a dose-response manner (compared to NLR below 3, Odds Ratio [OR]=1.35; 95%CI:1.10-1.67 for NLR 3-5; OR=1.47; 95%CI:1.16-1.85 for NLR above 5). NLR above 3 and sarcopenia were also independently associated with survival (Hazard Ratio [HR]=1.65; 95%CI:1.45-1.98 for overall death and HR=1.29; 95%CI:1.09-1.53 for CRC death); patients with both sarcopenia and NLR above 3 (versus neither), had double the risk of death overall (HR=2.53; 95%CI:1.87-3.41) and from CRC (HR=2.19; 95%CI:1.74-2.75). Conclusions and Relevance: Host inflammatory/immune response shortly prior to diagnosis predicts muscularity at diagnosis. Low muscle combined with systemic inflammation predicts worse CRC prognosis regardless of stage. A better understanding of the crosstalk between inflammatory/immune responses and the onset of changes in skeletal muscle may open new therapeutic avenues to improve cancer outcomes. Citation Format: Elizabeth M. Cespedes Feliciano, Candyce H. Kroenke, Jeffrey Meyerhardt, Carla M. Prado, Patrick T. Bradshaw, Marilyn Kwan, Jingjie Xiao, Stacey Alexeef, Erin K. Weltzien, Adriemme L. Castillo, Bette J. Caan. Systemic inflammation and sarcopenia predict colorectal cancer survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2250. doi:10.1158/1538-7445.AM2017-2250

Emerging research suggests that body composition can predict toxicity of certain chemotherapeutic agents. We used data from a clinical study to investigate associations between body composition and combined DOXIL (pegylated liposomal doxorubicin; PLD) and trabectedin (Yondelis) treatment, an effective treatment for ovarian cancer that shows high interpatient variation in toxicity profile. Patients (n = 74) participating in a phase III randomized trial of relapsed advanced ovarian cancer receiving PLD (30 mg/m2) and trabectedin (1.1 mg/m2) were included. Muscle tissue was measured by analysis of computerized tomography images, and an extrapolation of muscle and adipose tissue to lean body mass (LBM) and fat mass (FM) were employed. Toxicity profile after cycle 1 was used and graded according to the National Cancer Institute Common Toxicity Criteria (version 3). Patients presented with a wide range of body composition. In overweight and obese patients (body mass index (BMI) ≥ 25 kg/m2, n = 48) toxicity was more prevalent in those with lower BMI (p = 0.028) and a lower FM (n = 43, p = 0.034). Although LBM alone was not predictive of toxicity, a lower FM/LBM ratio was the most powerful variable associated with toxicity (p = 0.006). A different pattern emerged among normal weight patients (n = 26) where toxicity was rare among patients with smaller BMI (2). A clear association between both FM and LBM (primarily driven by FM) in explaining PLD plus trabectedin toxicity emerged, but only in individuals with excess body weight, with a lower ratio predicting higher exposure and risk for toxicity.

Although obesity is a well-known risk factor for cancer, the association between obesity and cancer survival remains controversial. This is partially due to the inability of conventional obesity measures to directly assess adiposity or adipose tissue distribution. As a metabolic organ, visceral adipose tissue (VAT) secrets a variety of cytokines and cytokine-like factors, potentially affecting cancer survival. The objective of this review was to investigate the influence of imaging-assessed VAT on cancer survival. A total of 22 studies assessing the impact of visceral adiposity on survival were included. Negative associations between VAT and survival were more frequently observed among patients with colorectal (four of six studies) and pancreatic (three of five studies) cancers, compared to higher VAT predicting longer survival in most studies of renal cell carcinoma patients (four of five studies). Methodological limitations, including unstandardised VAT measurement methods, lack of other body composition measurement (i.e. muscle mass), small sample size and heterogeneous cohort characteristics, may explain controversial findings related to the impact of VAT on cancer survival.

Physicians and investigators have sought to determine the relationship between body mass index (BMI [calculated as weight in kilograms divided by height in meters squared]) and colorectal cancer (CRC) outcomes, but methodologic limitations including sampling selection bias, reverse causality, and collider bias have prevented the ability to draw definitive conclusions.To evaluate the association of BMI at the time of, and following, colorectal cancer (CRC) diagnosis with mortality in a complete population using causal diagrams.This retrospective observational study with prospectively collected data included a cohort of 3408 men and women, ages 18 to 80 years, from the Kaiser Permanente Northern California population, who were diagnosed with stage I to III CRC between 2006 and 2011 and who also had surgery.Body mass index at diagnosis and 15 months following diagnosis.Hazard ratios (HRs) for all-cause mortality and CRC-specific mortality compared with normal-weight patients, adjusted for sociodemographics, disease severity, treatment, and prediagnosis BMI.This study investigated a cohort of 3408 men and women ages 18 to 80 years diagnosed with stage I to III CRC between 2006 and 2011 who also had surgery. At-diagnosis BMI was associated with all-cause mortality in a nonlinear fashion, with patients who were underweight (BMI18.5; HR, 2.65; 95% CI, 1.63-4.31) and patients who were class II or III obese (BMI ≥35; HR, 1.33; 95% CI, 0.89-1.98) exhibiting elevated mortality risks, compared with patients who were low-normal weight (BMI 18.5 to23). In contrast, patients who were high-normal weight (BMI 23 to25; HR, 0.77; 95% CI, 0.56-1.06), low-overweight (BMI 25 to28; HR, 0.75; 95% CI, 0.55-1.04), and high-overweight (BMI 28 to30; HR, 0.52; 95% CI, 0.35-0.77) had lower mortality risks, and patients who were class I obese (BMI 30 to35) showed no difference in risk. Spline analysis confirmed a U-shaped relationship in participants with lowest mortality at a BMI of 28. Associations with CRC-specific mortality were similar. Associations of postdiagnosis BMI and mortality were also similar, but patients who were class I obese had significantly lower all-cause and cancer-specific mortality risks.In this study, body mass index at the time of diagnosis and following diagnosis of CRC was associated with mortality risk. Though evidence shows that exercise in patients with cancer should be encouraged, findings suggest that recommendations for weight loss in the immediate postdiagnosis period among patients with CRC who are overweight may be unwarranted.

Microgeneration using solar photovoltaic systems is becoming increasingly popular in residential households as such systems allow households to use a renewable energy source, while also reducing their reliance on the electricity grid, to fulfill their electricity demand. In this study, we explore the attractiveness of PV microgeneration systems of different capacities in the absence of incentives and net metering options and under both flat and variable tariff scenarious. Smaller systems that are below 1 kW in capacity are more attractive under such conditions, however, at current cost levels, they still remain economically unattractive. The cost levels which allow for these PV systems to be economically viable are also determined.

Wind power is the fastest growing electricity generation source in the United States and is expected to play an increasing role in the electricity system. The variable and uncertain nature of wind power will require changes in the operation of the grid under higher penetration rates. In order to understand the changes necessary at both the planning and operational levels we propose a stochastic optimization approach that enables the consideration of the variable output of wind power as well as the costs of wind farm construction. Results from a small example system are used to illustrate the advantages of the approach.

As wind energy takes on an increasingly larger role in regional electricity generation portfolios, the power generation variability introduced into the system by wind farms may begin to diminish the positive effect of further additions of such farms. Large scale energy storage systems as a result of which otherwise wasted wind power could be stored and used when needed could become an attractive alternative for investment. The interplay between investment in new wind farms and energy storage is examined in this paper. A multi-paradigm model is adapted to examine increasingly higher levels of wind power generation and to undertake a comparison between equivalent investments in wind farms and electricity storage facilities.