RESUMEN
Quick, efficient, fully automated open-source programs to segment muscle and adipose tissues from computed tomography (CT) images would be a great contribution to body composition research. This study examined the concordance of cross-sectional areas (CSA) and densities for muscle, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and intramuscular adipose tissue (IMAT) from CT images at the third lumbar (L3) between an automated neural network (test method) and a semi-automatic human-based program (reference method). Concordance was further evaluated by disease status, sex, race/ethnicity, BMI categories. Agreement statistics applied included Lin's Concordance (CCC), Spearman correlation coefficient (SCC), Sorensen dice-similarity coefficient (DSC), and Bland−Altman plots with limits of agreement (LOA) within 1.96 standard deviation. A total of 420 images from a diverse cohort of patients (60.35 ± 10.92 years; body mass index (BMI) of 28.77 ± 7.04 kg/m2; 55% female; 53% Black) were included in this study. About 30% of patients were healthy (i.e., received a CT scan for acute illness or pre-surgical donor work-up), while another 30% had a diagnosis of colorectal cancer. The CCC, SCC, and DSC estimates for muscle, VAT, SAT were all greater than 0.80 (>0.80 indicates good performance). Agreement analysis by diagnosis showed good performance for the test method except for critical illness (DSC 0.65−0.87). Bland−Altman plots revealed narrow LOA suggestive of good agreement despite minimal proportional bias around the zero-bias line for muscle, SAT, and IMAT CSA. The test method shows good performance and almost perfect concordance for L3 muscle, VAT, SAT, and IMAT per DSC estimates, and Bland−Altman plots even after stratification by sex, race/ethnicity, and BMI categories. Care must be taken to assess the density of the CT images from critically ill patients before applying the automated neural network (test method).
Asunto(s)
Composición Corporal , Tomografía Computarizada por Rayos X , Tejido Adiposo , Índice de Masa Corporal , Femenino , Humanos , Masculino , Redes Neurales de la Computación , Tomografía Computarizada por Rayos X/métodosRESUMEN
Visceral adipose tissue (VAT) but not subcutaneous adipose tissue (SAT) is associated with obesity-related diseases including colorectal cancer (CRC). Superficial SAT (SSAT) and deep SAT (DSAT), components of SAT, also appear to independently influence disease risk. These abdominal adipose tissues (AATs) are not extensively studied in connection with CRC and have not been explored in the United States despite known racial variations in body composition. We conducted a case-control study that compared associations between AAT with CRC risk and race of African-American (AA) and non-Hispanic white (NHW) men with incident CRC matched by age, body mass index, and race (N = 158, 79/group). Cross-sectional computed tomography images were used for assessment of AAT. Overall cases and controls had similar VAT areas (140 ± 192 vs 149 ± 152 cm2, P-value = 0.93); however, cases had lower SSAT than controls (88 ± 39 vs 112 ± 65 cm2, P < 0.01). Among controls, AA had significantly lower VAT (114 ± 168 vs 180 ± 167, P < 0.01) than NHW. Conditional logistic regression revealed that AA men with greater SSAT had lower odds for CRC (odds ratio [OR]: 0.24, 95% confidence interval [CI] 0.07-0.85). Our findings indicate that VAT does vary between cases and controls by race; however, this variation is not a risk factor for CRC. The negative association between CRC and SSAT in AA men warrants further investigation.
Asunto(s)
Neoplasias Colorrectales/etnología , Neoplasias Colorrectales/etiología , Grasa Intraabdominal/fisiopatología , Adulto , Negro o Afroamericano , Composición Corporal , Estudios de Casos y Controles , Humanos , Modelos Logísticos , Persona de Mediana Edad , Obesidad Abdominal/complicaciones , Factores de Riesgo , Población BlancaRESUMEN
BACKGROUND: Sarcopenia is defined as the loss of muscle mass and function and has been associated with worsened outcomes, including disability and mortality. The aim of this study was to describe the prevalence of sarcopenia in patients who had an abdominal computed tomography (CT) scan completed within 7 days of hospital admission. METHODS: A retrospective study was conducted. Adult patients admitted to either the general medical or surgical floor were included. Muscle function was assessed using handgrip strength (HGS, kg), completed within the first 48 hours of admission. Skeletal muscle index (SMI, kg/m2 ) at the third lumber region was calculated among patients who had an abdominal CT scan completed within 7 days of admission. Sarcopenia was identified by the combination of low SMI and HGS. The primary outcome was the percentage of patients diagnosed with sarcopenia. RESULTS: A total of 1318 patients were admitted; 11% (n = 141) had an abdominal CT scan completed within 7 days of admission. Only race and prevalence of malnutrition were different between patients who did and did not have a CT completed. The overall prevalence of sarcopenia was 13% (n = 18/141). Additionally, 39% of the sample was at risk for sarcopenia, with either low SMI (n = 13/141) or low HGS (n = 42/141). CONCLUSIONS: Overall prevalence of sarcopenia was low, but more than one-third of patients had either low SMI or low HGS. Minimal differences were observed between patients who did and did not have an abdominal CT scan completed upon admission.
Asunto(s)
Fuerza de la Mano , Sarcopenia , Adulto , Humanos , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/patología , Prevalencia , Estudios Retrospectivos , Sarcopenia/diagnóstico por imagen , Sarcopenia/epidemiología , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVES: To determine the extent of agreement between a handheld ultrasound (US) attached to an android tablet and the reference method dual energy x-ray absorptiometry (DXA) for the measurement of adiposity. METHODS: A whole-body DXA scan and abdominal adipose tissue thickness measurements using a handheld US were obtained from 104 adults (63 females, 41 males). Body fat percent (BF%), total fat mass (kg), and trunk fat mass (kg) were obtained from DXA. Subcutaneous adipose tissue (SAT), superficial subcutaneous adipose tissue (SSAT), and deep subcutaneous adipose tissue (DSAT) thickness were obtained from US. Sex-specific total fat mass, trunk fat mass, and BF% estimates by US were compared with DXA. Spearman's correlations and Bland-Altman plots were used to assess agreement between the methods. RESULTS: US SAT correlated strongly with total fat mass for both females (rs = 0.74) and males (rs = 0.87) as did trunk fat mass (females, rs = 0.81; males, rs = 0.83); as did SSAT and DSAT (females: rs = 0.65 and rs = 0.66; males: rs = 0.63 and rs = 0.85, respectively, all p-values < 0.0001). Bland-Altman plots demonstrated strong agreement for total and trunk fat mass for both males and females. For BF%, acceptable limits of agreement were observed for males but not for females, substantial proportional bias as indicated by a negative slope was noted for BF% using SAT (r = -0.298, p = 0.0177). CONCLUSION: The handheld US and technique to analyze abdominal adipose tissue thickness showed strong agreement with DXA results and generated highly comparable estimates for total and trunk fat mass for both sexes.
Asunto(s)
Tejido Adiposo , Adiposidad , Absorciometría de Fotón , Tejido Adiposo/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Grasa Subcutánea/diagnóstico por imagen , UltrasonografíaRESUMEN
Body composition refers to the proportional content of body fat mass and lean body mass that can lead to a continuum of different phenotypes ranging from cachectic/sarcopenic state to obesity. The heterogenetic phenotypes of body composition can contribute to formation of some cancer types and can sometimes lead to disparate outcomes. Both of these extremes of the spectrum exist in patients with non-small cell lung carcinoma (NSCLC). The discovery of new pathways that drive tumorigenesis contributing to cancer progression and resistance have expanded our understanding of cancer biology leading to development of new targeted therapies including tyrosine kinase inhibitors (TKI) and immune checkpoint inhibitors (ICI) that have changed the landscape of NSCLC treatment. However, in the new era of precision medicine, the impact of body composition phenotypes on treatment outcomes and survival is now being elucidated. In this review, we will discuss the emerging evidence of a link between body composition and outcomes in patients with NSCLC treated with TKI and ICI. We will also discuss suggested mechanisms by which body composition can impact tumor behavior and anti-tumor immunological response.
RESUMEN
Diagnostic computed tomography (CT) scans provide numerous opportunities for body composition analysis, including quantification of abdominal circumference, abdominal adipose tissues (subcutaneous, visceral, and intermuscular), and skeletal muscle (SM). CT scans are commonly performed for diagnostic purposes in clinical settings, and methods for estimating abdominal circumference and whole-body SM mass from them have been reported. A supine abdominal circumference is a valid measure of waist circumference (WC). The valid correlation between a single cross-sectional CT image (slice) at third lumbar (L3) for abdominal SM and whole-body SM is also well established. Sarcopenia refers to the age-associated decreased in muscle mass and function. A single dimensional definition of sarcopenia using CT images that includes only assessment of low whole-body SM has been validated in clinical populations and significantly associated with negative outcomes. However, despite the availability and precision of SM data from CT scans and the relationship between these measurements and clinical outcomes, they have not become a routine component of clinical nutrition assessment. Lack of time, training, and expense are potential barriers that prevent clinicians from fully embracing this technique. This tutorial presents a systematic, step-by-step guide to quickly quantify abdominal circumference as a proxy for WC and SM using a cross-sectional CT image from a regional diagnostic CT scan for clinical identification of sarcopenia. Multiple software options are available, but this tutorial uses ImageJ, a free public-domain software developed by the National Institutes of Health.
Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Músculo Esquelético/diagnóstico por imagen , Sarcopenia/diagnóstico , Programas Informáticos , Tomografía Computarizada por Rayos X , Composición Corporal , Femenino , Guías como Asunto , Humanos , Región Lumbosacra/diagnóstico por imagen , Masculino , Músculo Esquelético/patología , National Institutes of Health (U.S.) , Estados Unidos , Circunferencia de la CinturaRESUMEN
INTRODUCTION: The preschool years provide a unique window of opportunity to intervene on obesity-related lifestyle risk factors during the formative years of a child's life. The purpose of this study was to assess the impact of a preschool-based obesity prevention effectiveness trial at 1-year follow-up. DESIGN: RCT. SETTINGS/PARTICIPANTS: Primarily African American children (aged 3-5 years, N=618) attending Head Start preschool programs administered by Chicago Public Schools. METHODS: Eighteen preschools were randomly assigned in 2007-2008 to receive either (1) a 14-week teacher-delivered intervention focused on healthy lifestyle behaviors or (2) a 14-week teacher-delivered general health curriculum (control group). MAIN OUTCOME MEASURES: The primary outcome, BMI, was measured at baseline, postintervention, and 1-year follow-up. Diet and screen time behaviors were also assessed at these time points. Multilevel mixed effects models were used to test for between-group differences. Data were analyzed in 2014. RESULTS: Significant between-group differences were observed in diet, but not in BMI z-score or screen time at 1-year follow-up. Diet differences favored the intervention arm over controls in overall diet quality (p=0.02) and in subcomponents of diet quality, as measured by the Healthy Eating Index-2005, and in fruit intake (servings/day, excludes juice) (p=0.02). Diet quality worsened more among controls than the intervention group at 1-year follow-up. CONCLUSIONS: The adaptation of Hip-Hop to Health Jr. produced modest benefits in diet quality but did not significantly impact weight gain trajectory. Not unlike other effectiveness trials, this real-world version delivered by Head Start teachers produced fewer benefits than the more rigorous efficacy trial. It is important to understand and build upon the lessons learned from these types of trials so that we can design, implement, and disseminate successful evidence-based programs more widely and effectively. TRIAL REGISTRATION: This study is registered at www.clinicaltrials.gov NCT00241878.
Asunto(s)
Índice de Masa Corporal , Conductas Relacionadas con la Salud , Promoción de la Salud/organización & administración , Obesidad/prevención & control , Servicios de Salud Escolar/organización & administración , Negro o Afroamericano , Chicago , Preescolar , Dieta , Ejercicio Físico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Conducta SedentariaRESUMEN
OBJECTIVE: This pilot study tested the feasibility of Family-Based Hip-Hop to Health, a school-based obesity prevention intervention for 3-5-year-old Latino children and their parents, and estimated its effectiveness in producing smaller average changes in BMI at 1-year follow-up. DESIGN AND METHODS: Four Head Start preschools administered through the Chicago Public Schools were randomly assigned to receive a Family-Based Intervention (FBI) or a General Health Intervention (GHI). RESULTS: Parents signed consent forms for 147 of the 157 children enrolled. Both the school-based and family-based components of the intervention were feasible, but attendance for the parent intervention sessions was low. Contrary to expectations, a downtrend in BMI Z-score was observed in both the intervention and control groups. CONCLUSIONS: While the data reflect a downward trend in obesity among these young Hispanic children, obesity rates remained higher at 1-year follow-up (15%) than those reported by the National Health and Nutrition Examination Survey (2009-2010) for 2-5-year-old children (12.1%). Developing evidence-based strategies for obesity prevention among Hispanic families remains a challenge.