Association of physical activity and visceral adipose tissue in older women and men

The Association Between Visceral Obesity and Postoperative Outcomes in Elderly Patients With Colorectal Cancer

Background

The impact of visceral obesity on the postoperative complications of colorectal cancer in elderly patients has not been well studied. This study aims to explore the influence of visceral obesity on surgical outcomes in elderly patients who have accepted a radical surgery for colorectal cancer.

Methods

Patients aged over 65 year who had undergone colorectal cancer resections from January 2015 to September 2020 were enrolled. Visceral obesity is typically evaluated based on visceral fat area (VFA) which is measured by computed tomography (CT) imaging. Univariate and multivariate analyses were performed to analyze parameters related to short-term outcomes.

Results

A total of 528 patients participated in this prospective study. Patients with visceral obesity exhibited the higher incidence of total (34.1% vs. 18.0%, P < 0.001), surgical (26.1% vs. 14.6%, P = 0.001) and medical (12.6% vs. 6.7%, P = 0.022) complications. Based on multivariate analysis, visceral obesity and preoperative poorly controlled hypoalbuminemia were considered as independent risk factors for postoperative complications in elderly patients after colorectal cancer surgery.

Conclusions

Visceral obesity, evaluated by VFA, was a crucial clinical predictor of short-term outcomes after colorectal cancer surgery in elderly patients. More attentions should be paid to these elderly patients before surgery.

Protein, Calcium, Vitamin D Intake and 25(OH)D Status in Normal Weight, Overweight, and Obese Older Adults: A Systematic Review and Meta-Analysis

The aging process is often accompanied by increase in body weight. Older adults with overweight or obesity might have an overconsumption in energy that is accompanied by inadequate intake of protein, vitamin D, and calcium. It is unclear if intake of protein and vitamin D and calcium is sufficient in older adults with overweight/obesity, and whether it differs from older adults with normal weight, since a recent overview of the literature review is lacking. Therefore, we systematically analyzed the current evidence on differences in nutrient intake/status of protein, vitamin D and calcium between older adults with different body mass index (BMI) categories. Randomized controlled trials and prospective cohort studies were identified from PubMed and EMBASE. Studies reporting nutrient intake/status in older adults aged ≥50 years with overweight/obesity and studies comparing between overweight/obesity and normal weight were included. Nutrient intake/status baseline values were reviewed and when possible calculated for one BMI category (single-group meta-analysis), or compared between BMI categories (meta-analysis). Nutrient intake/status was compared with international recommendations. Mean protein (N = 8) and calcium intake (N = 5) was 0.98 gram/kilogram body weight/day (g/kg/d) [95% Confidence Interval (CI) 0.89-1.08] and 965 mg [95% CI: 704-1225] in overweight/obese. Vitamin D intake was insufficient in all BMI categories (N = 5). The pooled mean for vitamin D intake was 6 ug [95% CI 4-9]. For 25(OH)D, the pooled mean was 54 nmol/L [95% CI 45-62], 52 nmol/L [95% CI 46-58], and 48 nmol/l [95% CI 33-62] in normal (N = 7), combined overweight and obese (N = 12), and obese older adults (N = 4), respectively. In conclusion, older adults with overweight and obesity have a borderline sufficient protein and sufficient calcium intake, but insufficient vitamin D intake. The 25(OH)D concentration is deficient for the obese older adults.

Pharmacological Treatment of Sarcopenia

Sarcopenia has been acquiring a growing importance in the scientific literature and in doctors' offices. As the population ages, it becomes increasingly essential to know, prevent, and treat this clinical condition. The purpose of the present review is to bring up the current evidence on the diagnosis of this pathology, in a practical way, as well as the main current treatment options.

Role of exercise on visceral adiposity after spinal cord injury: a cardiometabolic risk factor

PURPOSE

Visceral adipose tissue (VAT) is associated with cardiometabolic disease risk in able-bodied (AB) populations. However, the underlying mechanisms of VAT-induced disease risk are unknown in persons with spinal cord injury (SCI). Potential mechanisms of VAT-induced cardiometabolic dysfunction in persons with SCI include systemic inflammation, liver adiposity, mitochondrial dysfunction, and anabolic deficiency. Moreover, how exercise interventions impact these mechanisms associated with VAT-induced cardiometabolic dysfunction are still being explored.

METHODS

A search for relevant scientific literature about the effects of exercise on VAT and cardiometabolic health was conducted on the PubMed database. Literature from reference lists was also included when appropriate.

RESULTS

Both aerobic and resistance exercise training beneficially impact health and VAT mass via improving mitochondrial function, glucose effectiveness, and inflammatory signaling in SCI and AB populations. Specifically, aerobic exercise appears to also modulate cellular senescence in AB populations and animal models, while resistance exercise seems to augment anabolic signaling in persons with SCI.

CONCLUSIONS

The current evidence supports regular engagement in exercise to reduce VAT mass and the adverse effects on cardiometabolic health in persons with SCI. Future research is needed to further elucidate the precise mechanisms by which VAT negatively impacts health following SCI. This will likely facilitate the development of rehabilitation protocols that target VAT reduction in persons with SCI.

Increased Omega-3 Fatty Acid Intake is Inversely Associated with Sarcopenic Obesity in Women but not in Men, Based on the 2014-2018 Korean National Health and Nutrition Examination Survey

(1) Background: Omega-3 fatty acids (ω3FAs) are known to improve protein anabolism, increase the sensitivity to anabolic stimuli, decrease lipogenesis, and stimulate lipid oxidation. We aim to investigate whether ω3FAs are associated with the prevalence of sarcopenic obesity (SO). (2) Methods: Data were obtained from the 2014–2018 Korean National Health and Nutrition Examination Survey. The ratio of daily ω3FA intake to energy intake (ω3FA ratio) was categorized into four quartile groups. (3) Results: The prevalence of SO from Q1 to Q4 was 8.9%, 11.3%, 11.0%, and 9.8% respectively, in men and 17.4%, 14.0%, 13.9%, and 10.1% respectively, in women. The ω3FA ratio in individuals with and without SO were 1.0% and 0.9% in men (p-value = 0.271) respectively, and 0.8% and 1.0% in women (p-value = 0.017), respectively. Compared with Q1, odds ratios (95% confidence intervals) of Q2, Q3, and Q4 of ω3FA ratios were 1.563 (0.802–3.047), 1.246 (0.611–2.542), and 0.924 (0.458–1.864) respectively, in men and 0.663 (0.379–1.160), 0.640 (0.372–1.102), and 0.246 (0.113–0.534) respectively, in women, after fully adjusting for confounding factors. (4) Conclusions: The ω3FA ratio was significantly higher in older females without SO than in older females with SO. The ω3FA ratio was associated with the prevalence of SO in elderly females.

Lifestyle factors and visceral adipose tissue: Results from the PREDIMED-PLUS study

BACKGROUND

Visceral adipose tissue (VAT) is a strong predictor of cardiometabolic health, and lifestyle factors may have a positive influence on VAT depot. This study aimed to assess the cross-sectional associations between baseline levels of physical activity (PA), sedentary behaviours (SB) and adherence to the Mediterranean diet (MedDiet) with VAT depot in older individuals with overweight/obesity and metabolic syndrome.

METHODS

Baseline data of the PREDIMED-Plus study including a sample of 1,231 Caucasian men and women aged 55-75 years were used. Levels of leisure-time PA (total, light, and moderate-to-vigorous, in METs·min/day) and SB (total and TV-viewing, in h/day) were evaluated using validated questionnaires. Adherence to the MedDiet was evaluated using a 17-item energy-restricted MedDiet (erMedDiet) screener. The chair-stand test was used to estimate the muscle strength. VAT depot was assessed with DXA-CoreScan. Multivariable adjusted linear regression models were used to evaluate the association between lifestyle factors and VAT. For the statistics we had used multiadjusted linear regression models.

RESULTS

Total leisure-time PA (100 METs·min/day: β -24.3g, -36.7;-11.9g), moderate-to-vigorous PA (β -27.8g, 95% CI -40.8;-14.8g), chair-stand test (repeat: β -11.5g, 95% CI -20.1;-2.93g) were inversely associated, and total SB (h/day: β 38.2g, 95% CI 14.7;61.7) positively associated with VAT. Light PA, TV-viewing time and adherence to an erMedDiet were not significantly associated with VAT.

CONCLUSIONS

In older adults with overweigh/obesity and metabolic syndrome, greater PA, muscle strength, and lower total SB were associated with less VAT depot. In this study, adherence to an erMedDiet was not associated with lower VAT.

Inter-muscular adipose tissue is associated with adipose tissue inflammation and poorer functional performance in central adiposity

BACKGROUND

The presence of concomitant sarcopenia and obesity in sarcopenic obesity (SO) confers worse functional, morbidity and mortality outcomes compared to either alone. Excess adiposity and central redistribution of fats are associated with systemic inflammation and ectopic tissue fat infiltration in forms of Intermuscular adipose tissue (IMAT). Our study examines the profile of IMAT across a spectrum of body compositions and associations with physical performance and inflammatory biomarkers including Monocyte Chemoattractant Protein-1 (MCP-1), a novel biomarker of adipose tissue inflammation.

METHODS

187 community dwelling elderly participants were recruited and classified into 4 subgroups: normal, obese, sarcopenia and SO, using validated criteria for sarcopenia and waist circumference to define central obesity. We performed magnetic resonance imaging of mid-thigh sections to segment IMAT and muscle. Participants were assessed for muscle strength, physical performance and blood inflammatory biomarkers of interleukin-6, C-Reactive Protein and MCP-1. We examined correlation of IMAT(ratio) with muscle function measures and blood biomarkers. Multiple regression analyses were used to examine the association of body composition types and IMAT(ratio) with muscle function.

RESULTS

IMAT(ratio) was highest in SO and obese groups. Overall, higher IMAT(ratio) is significantly associated with raised MCP-1, lower gait speed and muscle strength. SO had lowest scores in Short Physical Performance Battery (SPPB), gait speed, hand-grip and knee extension strength. IMAT(ratio) is independently associated with SPPB and handgrip strength, whilst SO is independently associated with muscle strength.

CONCLUSION

Our results suggest the possible role of IMAT as a candidate imaging biomarker for adipose tissue inflammation and associated poorer functional outcomes in SO.

Impact of Visceral Obesity and Sarcopenia on Short-Term Outcomes After Colorectal Cancer Surgery

BACKGROUND

With the increased prevalence of obesity and sarcopenia, those patients with both visceral obesity and sarcopenia were at higher risk of adverse outcomes.

AIM

The aim of this study was to ascertain the combined impact of visceral obesity and sarcopenia on short-term outcomes in patients undergoing colorectal cancer surgery.

METHODS

We conducted a prospective study from July 2014 to February 2017. Patients' demographic, clinical characteristics, physical performance, and postoperative short-term outcomes were collected. Patients were classified into four groups according to the presence of sarcopenia or visceral obesity. Clinical variables were compared. Univariate and multivariate analyses evaluating the risk factors for postoperative complications were performed.

RESULTS

A total of 376 patients were included; 50.8 and 24.5% of the patients were identified as having "visceral obesity" and "sarcopenia," respectively. Patients with sarcopenia and visceral obesity had the highest incidence of total, surgical, and medical complications. Patients with sarcopenia or/and visceral obesity all had longer hospital stays and higher hospitalization costs. Age ≥ 65 years, visceral obesity, and sarcopenia were independent risk factors for total complications. Rectal cancer and visceral obesity were independent risk factors for surgical complications. Age ≥ 65 years and sarcopenia were independent risk factors for medical complications. Laparoscopy-assisted operation was a protective factor for total and medical complications.

CONCLUSION

Patients with both visceral obesity and sarcopenia had a higher complication rate after colorectal cancer surgery. Age ≥ 65 years, visceral obesity, and sarcopenia were independent risk factors for total complications. Laparoscopy-assisted operation was a protective factor.

Sarcopenic Obesity in Elderly Korean Women: A Nationwide Cross-sectional Study

Background

Sarcopenia causes loss of muscle mass in the elderly and is associated with development of metabolic syndrome in those with obesity. This study evaluated the prevalence of sarcopenic obesity (SO) in healthy Korean elderly women.

Methods

This study was based on data from the Korea National Health and Nutrition Examination Survey IV and V, 2008–2011. Whole body dual energy X-ray absorptiometry and body mass index measurement were performed for all patients. Women aged 65 years or older were included in this study. Total appendicular extremity muscle mass was used to determine the skeletal muscle mass index.

Results

Of 2,396 women aged 65 years or older, a total of 1,491 (62.2%) were underweight, normal weight, or overweight, while 905 (37.8%) were obese. The prevalence of sarcopenia using a cut-off value of 5.4 kg/m² was 64.9% (63/97) in underweight women, 38.2% (320/838) in normal weight women, 17.1% (95/556) in overweight women, and 6.1% (55/905) in obese women.

Conclusions

The prevalence of sarcopenia was different among groups. The prevalence rate in obese women was lower than that in non-obese women. SO is a new category of obesity in older adults with high adiposity coupled with low muscle mass. The prevalence of SO was lower than that in previous studies because of differences in the definition. A consensus definition of SO needs to be established.

The metabolic syndrome: an emerging risk state for cardiovascular disease

The common clustering of glucose intolerance, insulin resistance, abdominal adiposity, elevated blood pressure, and low HDL cholesterol is referred to as metabolic syndrome. Individuals with this syndrome have an increased risk of developing cardiovascular disease (CVD). The World Health Organisation and the National Cholesterol Education Programme’s Adult Treatment Panel III (NCEP-ATP III) have outlined specific diagnostic criteria for the diagnosis of the metabolic syndrome to help in the Identification of this syndrome in clinical practice. While the WHO criteria were specifically developed for use in research, the NCEP criteria are useful in clinical diagnosis of the metabolic syndrome. The metabolic syndrome is amenable to lifestyle modifications such as increased physical activity, weight loss, and possibly intake of low-glycemic foods. Drug therapy may be used to treat individual components of the syndrome such as elevated blood pressure and dyslipidemia. To control elevated glucose levels (when there is failure of lifestyle modification), medications such as metformin, thiazolidinedione derivatives and alpha glucosidase inhibitors may be used.

Association of Habitual Patterns and Types of Physical Activity and Inactivity with MRI-Determined Total Volumes of Visceral and Subcutaneous Abdominal Adipose Tissue in a General White Population

Population-based evidence for the role of habitual physical activity (PA) in the accumulation of visceral (VAT) and subcutaneous (SAAT) abdominal adipose tissue is limited. We investigated if usual patterns and types of self-reported PA and inactivity were associated with VAT and SAAT in a general white population. Total volumes of VAT and SAAT were quantified by magnetic resonance imaging in 583 men and women (61 ± 11.9 y; BMI 27.2 ± 4.4 kg/m2). Past-year PA and inactivity were self-reported by questionnaire. Exploratory activity patterns (APAT) were derived by principal components analysis. Cross-sectional associations between individual activities, total PA in terms of metabolic equivalents (PA MET), or overall APAT and either VAT or SAAT were analyzed by multivariable-adjusted robust or generalized linear regression models. Whereas vigorous-intensity PA (VPA) was negatively associated with both VAT and SAAT, associations between total PA MET, moderate-intensity PA (MPA), or inactivity and VAT and/or SAAT depended on sex. There was also evidence of a threshold effect in some of these relationships. Total PA MET was more strongly associated with VAT in men (B = -3.3 ± 1.4; P = 0.02) than women (B = -2.1 ± 1.1; P = 0.07), but was more strongly associated with SAAT in women (B = -5.7 ± 2.5; P = 0.05) than men (B = -1.7 ± 1.6; P = 0.3). Men (-1.52 dm3 or -1.89 dm3) and women (-1.15 dm3 or -2.61 dm3) in the highest (>6.8 h/wk VPA) or second (4.0-6.8 h/wk VPA) tertile of an APAT rich in VPA, had lower VAT and SAAT, respectively, than those in the lowest (<4.0 h/wk VPA) tertile (P ≤ 0.016; P trend ≤ 0.0005). They also had lower VAT and SAAT than those with APAT rich in MPA and/or inactivity only. In conclusion, our results suggest that in white populations, habitual APAT rich in MPA might be insufficient to impact on accumulation of VAT or SAAT. APAT including ≥ 4.0-6.8 h/wk VPA, by contrast, are more strongly associated with lower VAT and SAAT.

Sarcopenia: a predictor of mortality and the need for early diagnosis and intervention

The term sarcopenia refers to the loss of muscle mass that occurs with aging. Sarcopenia is defined by the European Working Group on Sarcopenia in Older People (EWGSOP) as low muscle mass and low muscle function (strength and performance). Its prevalence varies depending on the definition used for it, but estimates propose a loss of approximately 8 % per decade until the age of 70 years; afterwards, the loss increases and ranges from 13 to 24 % per decade. Irrespective of how sarcopenia is defined, both low muscle mass and poor muscle strength are highly prevalent and important risk factors for disability and increased mortality in individuals as they age. In this review, we address age-related muscle loss and the risk factors of mortality, emphasizing the need for early diagnosis and intervention.

Preliminary evaluation of the prevalence of sarcopenia in obese patients from Southern Italy

OBJECTIVES

Sarcopenic obesity has not yet been widely defined. The aim of this study was to evaluate the prevalence of sarcopenia in a group of severely obese adults from southern Italy by using two different indexes: percentage of skeletal muscle mass (SMP) and skeletal muscle mass normalized for height (SMI); and to determine SMP and SMI cutoff points in a southern Italy reference population.

METHODS

Skeletal muscle mass of 131 consecutive obese adult outpatients (51 men and 80 women; ages 45-67 y; body mass index 44.6 ± 7.7 kg/m(2)), was assessed by bioimpedance analysis. SMP and SMI cutoff points to identify moderate and severe sarcopenia were calculated in a reference group of 500 young southern Italy adults (100 men and 400 women; ages 18-40 y; body mass index 25.2 ± 5.6 kg/m(2)) and applied to assess the prevalence of sarcopenia in the study population.

RESULTS

SMP cutoff points to identify moderate and severe sarcopenia were, 28.8% to 35.6% and ≤ 28.7% in men and 23.1% to 28.4% and ≤ 23% in women, respectively. The corresponding values for SMI were 8.44 to 9.53 kg/m(2) and ≤ 8.43 kg/m(2) in men, 6.49 to 7.32 kg/m(2) and ≤ 6.48 kg/m(2) in women. According to SMP, 23 of 51 (45.1%) men and 19 of 80 (23.8%) women were moderately sarcopenic; 28 of 51 (54.9%) men and 61 of 80 (76.3%) women met the definition of severe sarcopenia. Based on SMI, only 2 of 51 (3.9%) men were moderately sarcopenic.

CONCLUSIONS

This study confirms that sarcopenia rates vary widely in obese patients depending on the criteria used. SMP as a screening tool to identify a sarcopenia at-risk population.

Sarcopenia: definition, epidemiology, and pathophysiology

The epidemiological trends that characterize our generation are the aging of the population. Aging results in a progressive loss of muscle mass and strength called sarcopenia, which is Greek for 'poverty of flesh'. Sarcopenia could lead to functional impairment, physical disability, and even mortality. Today, sarcopenia is a matter of immense public concern for aging prevention. Its prevalence continues to rise, probably as a result of increasing elderly populations all over the world. This paper addressed the definition and epidemiology of sarcopenia and its underlying pathophysiology. In addition, we summarized the abundant information available in the literature related to sarcopenia, together with results from Korean sarcopenic obesity study (KSOS) that we performed.

Body composition and its association with cardiometabolic risk factors in the elderly: a focus on sarcopenic obesity

Important changes in body composition with aging are a progressive loss of muscle mass and increase of fat mass. Despite their enormous clinical importance, body composition changes such as sarcopenic obesity in the elderly are under-recognized. This study aimed to examine the relationship of body composition with a wide variety of cardiometabolic risk factors among 2943 subjects (1250 men and 1693 women) aged 60 years or older from Korean National Health Examination and Nutrition Survey (KNHANES). Sarcopenia was defined as an appendicular skeletal muscle mass (ASM) divided by weight (%) of < 1 SD below the sex-specific mean for young adults. Obesity was defined as a body mass index (BMI) ≥ 25 kg/m(2). Body composition was categorized into four non-overlapping groups: the sarcopenic obese, sarcopenic nonobese, nonsarcopenic obese, and nonsarcopenic nonobese groups. A wide variety of cardiometabolic risk factors, including blood pressure (BP), glucose tolerance indices, lipid profiles, inflammatory markers, and vitamin D level, were compared according to body composition group. The prevalence of sarcopenic obesity was 18.4% in men and 25.8% in women. In both sexes, the prevalence of vitamin D deficiency and metabolic syndrome was highly prevalent in the sarcopenic obese group. Serum insulin level, homeostasis model assessment of insulin resistance (HOMA-IR), triglyceride levels, and ferritin levels were the highest in the sarcopenic obese group in both men and women, whereas HDL-cholesterol and 25-hydroxyvitamin D (25(OH)D) levels were the lowest in the sarcopenic obese group. The sarcopenic obese group was more closely associated with insulin resistance, metabolic syndrome, and cardiovascular disease (CVD) risk factors than any other group in this elderly population.

Trends in general and abdominal obesity among Chinese children and adolescents 1993-2009

OBJECTIVE

This study aimed to examine the secular trends in body mass index (BMI) and waist circumference (WC), and the prevalence of general and abdominal obesity among Chinese children and adolescents from 1993 to 2009.

METHODS

Data were obtained from the China health and nutrition survey conducted from 1993 to 2009. 9693 children and adolescents aged 6-17 years were included in this study, with their height, weight and WC measured. General obesity was defined using the BMI cut-offs for overweight recommended by the International Obesity Task Force, and abdominal obesity was assessed when a WC is above the 90th percentile for gender and age.

RESULTS

Among the total participants, mean BMI and WC increased significantly over the period 1993-2009: BMI increased from 17.6 to 17.8 kg m(-2) , and WC increased from 61.4 to 63.1 cm (both increases P < 0.001). The prevalence of general obesity and abdominal obesity increased significantly over the period: general obesity (including overweight) rose from 6.1% to 13.1% and abdominal obesity from 4.9% to 11.7% (both increases P < 0.001). WC and abdominal obesity increased at a relatively higher rate than BMI and general obesity. Upward trends in the prevalence of general and abdominal obesity were observed in all subgroups of gender, age and region (all increases P < 0.05), except for abdominal obesity in girls aged 13-17 years (P = 0.102).

CONCLUSION

General and abdominal obesity increased significantly over the past 17 years in Chinese children.

Cross-sectional Relationship of Pedometer-Determined Ambulatory Activity to Indicators of Health

OBJECTIVE

To describe the cross-sectional relationship between an objective measure of walking (pedometer-determined steps/day) and general indicators of health, a prior diagnosis of one or more components of the metabolic syndrome, and self-reported occupational activity in a generally sedentary working population.

RESEARCH METHODS AND PROCEDURES

Steps/day were compared with previous diagnosis of one or more components of the metabolic syndrome (by self-administered questionnaire) and with general health indicators including BMI, waist circumference, resting heart rate, and blood pressure in 182 subjects in Prince Edward Island, Canada. Study participants were volunteer employees recruited from five workplaces where, in general, the job types were moderately or highly sedentary.

RESULTS

Steps/day were 7230 +/- SD 3447 for women (n = 153) and 8265 +/- 2849 (n = 21) for men. Pedometer-determined steps/day were associated inversely with BMI (r = -0.4005, p < 0.0001) in all participants and waist circumference in females only (r = -0.4303, p < 0.0001). There was a low correlation between steps/day and diastolic blood pressure in the whole sample (r = -0.2140, p = 0.0383). Participants who reported a prior diagnosis of one or more components of the metabolic syndrome (hypertension, hypercholesterolemia, heart disease, or type 2 diabetes) took fewer steps/day than healthy participants (p = 0.0254). Pedometer-determined steps/day were positively associated with self-reported occupational activity (p = 0.0002).

DISCUSSION

Fewer steps/day are associated with increased BMI, waist circumference, diastolic blood pressure, and components of the metabolic syndrome. Low occupational activity is a contributing factor to low total ambulatory activity.

Efeitos do treinamento aeróbio sobre o perfil lipídico de ratos com hipertireoidismo

Há poucos estudos analisando a importante relação entre o exercício físico, agudo e crônico, e alterações metabólicas decorrentes do hipertireoidismo. O objetivo do presente estudo foi analisar o efeito de quatro semanas de treinamento aeróbio sobre o perfil lipídico de ratos com hipertireoidismo experimental. Foram utilizados 45 ratos da linhagem Wistar, divididos aleatoriamente em quatro grupos: Controle Sedentário (CS) - administrados com salina durante o período experimental, não praticaram exercício físico (n = 12); Controle Treinado (CT) - administrados com salina, participaram do treinamento (n = 11); Hipertireoidismo Sedentário (HS) - induzidos ao hipertireoidismo, não praticaram exercício físico (n = 12); e Hipertireoidismo Treinado (HT) - induzidos ao hipertireoidismo, participaram do treinamento (n = 10). O treinamento aeróbio teve duração de quatro semanas, cinco vezes na semana, com duração de uma hora por sessão. Após o término do período experimental todos os ratos foram anestesiados em câmara de CO2 até sua sedação. Coletaram-se amostras de sangue para dosagem de colesterol total, triglicerídeos, HDL-colesterol e LDL-colesterol e hormônio T3; e amostras do coração, fígado, músculo gastrocnêmio e tecido adiposo das regiões mesentérica, retroperitonial e subcutânea para pesagem e dosagem de triglicerídeos. Para análise estatística utilizou-se ANOVA two-way, seguida do post hoc LSD de Fischer. Observaram-se menores valores de AGL no grupo HS quando comparado ao CS. O grupo HS teve nível de triglicerídeos significativamente superior nas regiões mesentérica, do gastrocnêmio e retroperitonial quando comparado com os grupos CS e CT, e apenas o tecido adiposo da região retroperitonial apresentou diferenças significativas na qual o grupo HT apresentou menor peso quando comparado com o grupo CS. Pode-se concluir que os ratos hipertireoidicos apresentaram perfil lipídico diferente dos ratos controle, e o treinamento aeróbio em ratos Wistar pode ter alterado o perfil lipídico dos animais com hipertireoidismo experimental quando comparados com o grupo sedentário e grupos controle.

Visceral adipose tissue in children and adolescents: a review

Research conducted among adults has mainly shown that visceral adipose tissue (VAT) is strongly linked to insulin resistance, type 2 diabetes, hypertension and dyslipidaemia, leading to increased risk of CVD or the metabolic syndrome. However, little is known about the aetiology, determinants and consequences of VAT in children. The present article reviews the current literature relating to the factors influencing visceral fat accumulation in children and adolescents. The literature used in the present study was collected by searching a PubMed database, in which studies up to 2008 exploring the factors influencing accumulation of visceral fat among children and youth were found on the basis of appropriate keywords. Further studies concerning different factors influencing deposition of VAT among children and youth should first of all concentrate on: carrying out long-term analyses among children of different ethnical groups, which should begin in the period of prepuberty and which should cover the whole period of puberty till adulthood; drawing up norms specifying the amount of VAT among healthy children; identification of anthropometric indicators which will help to determine the VAT:subcutaneous adipose tissue ratio in the most precise way; broader studies of the influence of eating habits on developing VAT deposit among children and youth.

Dietary predictors of visceral adiposity in overweight young adults

The purpose of the present study was to determine the dietary predictors of visceral adipose tissue (VAT) area in overweight young adults. A total of 109 young adults (fifty males and fifty-nine females) ate ad libitum in a university cafeteria for 14 d. All food and beverages consumed in the cafeteria were measured using observer-recorded weighed plate waste. Food consumption outside the cafeteria (i.e. snacks) was assessed by multiple-pass 24 h recall procedures. VAT was determined using computed tomography. Stepwise regression demonstrated that the best predictor of visceral adiposity in women was total dietary fat (P <or= 0.05). In men, the model for predicting visceral adiposity included Ca and total dietary fat. We concluded that total dietary fat is the best predictor of VAT area in both men and women. While this relationship was independent in women, in men there was a synergistic relationship between dietary fat consumption and Ca consumption in predicting VAT.

Visceral abdominal fat is correlated with whole-body fat and physical activity among 8-y-old children at risk of obesity

BACKGROUND

Abdominal fat is more related to health risk than is whole-body fat. Determining the factors related to children's visceral fat could result in interventions to improve child health.

OBJECTIVE

Given the effects of physical activity on adults' visceral fat, it was hypothesized that, after accounting for whole-body fat, physical activity would be inversely related to children's visceral (VAT), but not to subcutaneous (SAT), abdominal adipose tissue.

DESIGN

In this cross-sectional observational study conducted in forty-two 8-y-old children (21 boys, 21 girls) at risk of obesity [>75th body mass index (BMI) percentile, with at least one overweight parent], familial factors (eg, maternal BMI), historic weight-related factors (eg, birth weight), and the children's current physical activity (self-reported and measured with accelerometry) and diet were examined as potential correlates of the children's whole-body composition (measured with BMI and dual-energy X-ray absorptiometry) and abdominal fat distribution (measured by magnetic resonance imaging).

RESULTS

Accelerometer-measured physical activity was related to whole-body fat (r = -0.32, P < 0.10), SAT (r = -0.29, P < 0.10), and VAT (r = -0.43, P < 0.05). In regression models, whole-body fat was positively associated with and the only significant correlate of SAT. Whole-body fat was positively related and accelerometer-measured physical activity was negatively and independently related to the children's VAT.

CONCLUSIONS

Both SAT and VAT in 8-y-old children at risk of obesity are most closely associated with whole-body fat. However, after control for whole-body fat, greater physical activity is only associated with lower VAT, not SAT, in these children.

Leisure-Time Physical Activity and Health-Care Utilization in Older Adults

This study examined whether leisure-time physical activity (LTPA) was associated with health-care utilization in a racially diverse sample of rural and urban older adults. Community-dwelling adults (N= 1,000, 75.32 ± 6.72 years old) self-reported participating in LTPA and their use of the health-care system (physician visits, number and length of hospitalizations, and emergency-room visits). After controlling for variables associated with health and health-care utilization, older adults who reported lower levels of LTPA also reported a greater number of nights in the hospital in the preceding year. There was no support, however, for a relationship between LTPA and the other indicators of health-care utilization. Our findings suggest that being physically active might translate to a quicker recovery for older adults who are hospitalized. Being physically active might not only have health benefits for older persons but also lead to lower health-care costs.

Weight, fat mass, and central distribution of fat increase when women use depot-medroxyprogesterone acetate for contraception

OBJECTIVE

To compare longitudinal changes in weight, body fat, and ratio of central to peripheral fat mass among first-time depot-medroxyprogesterone acetate (DMPA) users to women using no hormonal contraception, and to evaluate user characteristics associated with that change.

DESIGN

Prospective longitudinal study.

SUBJECTS

Healthy women, aged 18-35 y, using DMPA for contraception (n=178) and women using no hormonal contraception (n=145).

MEASUREMENTS

Weight, body fat, and the central distribution of fat, measured at 3-month intervals for 30 months, by electronic scale and dual-energy X-ray absorptiometry (DEXA). The ratio of central to peripheral distribution of body fat was computed by dividing the body fat in the conventional DEXA trunk region of interest (ROI) by the ROI's that encompass the arms, hips and legs.

RESULTS

Women using DMPA had a significantly greater increase in all measures of fatness than women using no hormonal method of contraception (P<0.03). The observed weight of DMPA users increased from a mean of 69.4 kg (s.d.=16.9) at baseline to 75.5 kg (s.d.=25.0) at 30 months; an increase of 6.1 kg (8.8.%). Fat mass increased from a mean of 25.3 kg (s.d.=12.6 kg) at baseline to 31.4 kg (s.d.=17.8); an increase of 6.1 kg (23.6%) in DMPA users. The ratio of central to peripheral fat mass in DMPA users changed from 0.95 (s.d.=0.155) at baseline to 1.01(s.d.=0.198) at 30 months. In contrast, weight, fat mass and the ratio of central to peripheral fat mass of control participants remained virtually unchanged over the same time period. Women with higher baseline physical activity levels had a smaller increase in body fat (P=0.003) and the fat ratio (P=0.03), but not weight (P=0.48). No other user characteristics including, smoking, past oral contraceptive use or previous pregnancies predicted change in level of fatness.

CONCLUSIONS

This study has demonstrated a change in body composition toward greater fatness and toward a central redistribution of fat among DMPA users as compared to controls and provides important information to be used when counseling women regarding contraceptive methods. Given the potential long-term implication of these changes, further study is recommended to determine whether the gains in fatness are reversed following DMPA discontinuation and to examine the role of progestins in the development and maintenance of obesity.

Serum Lipoproteins in Overweight/Obese Postmenopausal Women

INTRODUCTION

This analysis was conducted to study the effect of a 1-yr moderate-intensity aerobic exercise program on serum lipoproteins among overweight/obese postmenopausal women.

METHODS

We randomized 173 sedentary (VO2max = 20.2 mL.kg(-1).min(-1)), overweight/obese women (body mass index (BMI) 25.0-42.0 kg.m(-2) or body fat > 33% if BMI 24.0-25.0) aged 50-75 yr, not using hormone therapy, living in the Seattle area, to an exercise intervention or stretching control group. The exercise intervention included facility and home-based exercise (45 min, 5 d.wk(-1) of moderate-intensity sports or recreational exercise). Total cholesterol (TC), triglycerides, and high-density lipoprotein (HDL) were determined by chemical assay; low-density lipoprotein (LDL) was then calculated.

RESULTS

Of the 173 women, 170 (98.3%) completed the study with exercisers averaging 176 (SD 91) min.wk(-1) of moderate- to vigorous-intensity (60%-75% HRmax) exercise, expending approximately 3828 kJ.wk(-1) (SD 2053). Exercisers, compared with stretchers, significantly increased their VO2max (+11%, P<0.001) and lost more body weight (-1.4 kg, P < 0.05), DEXA-% total body fat (-1.0, P < 0.005), L4-5 computed tomography intraabdominal fat (-8.6 cm2, P < 0.05) and subcutaneous abdominal fat (-28.8 cm2, P < 0.005) after 12 months. Mean (SD) baseline lipoprotein levels for TC, LDL, HDL, and triglycerides were 231 (39), 152 (39), 52 (12), and 135 (65) mg.dL(-1), respectively. We observed no significant change in serum lipoprotein levels among exercisers compared with stretchers at either 3 or 12 months postrandomization. We did not observe a statistically significant effect of exercise on serum lipoproteins in subgroups that changed their intraabdominal and subcutaneous fat, percent total body fat, or VO2max the most, or that adhered to the exercise regimen the most over 1 yr.

CONCLUSION

It appears that a year long moderate-intensity exercise program alone does not significantly alter serum lipoprotein levels among overweight/obese postmenopausal women.

Addition of aerobic exercise to dietary weight loss preferentially reduces abdominal adipocyte size

OBJECTIVE

To determine if hypocaloric diet, diet plus low-intensity exercise, and diet plus high-intensity exercise differentially influence subcutaneous abdominal and gluteal adipocyte size in obese individuals.

DESIGN

Longitudinal intervention study of hypocaloric diet, diet plus low-intensity exercise, and diet plus high-intensity exercise (calorie deficit = 2800 kcal/week, 20 weeks).

SUBJECTS

Forty-five obese, middle-aged women (BMI = 33.0+/-0.6 kg/m2, age = 58+/-1 years).

MEASUREMENTS

Body composition testing and adipose tissue biopsies were conducted before and after the interventions. Subcutaneous abdominal and gluteal adipocyte size was determined.

RESULTS

All three interventions reduced body weight, fat mass, percent fat, and waist and hip girths to a similar degree. Diet only did not change subcutaneous abdominal adipocyte size, whereas both diet plus exercise groups significantly reduced abdominal adipocyte size. Changes in abdominal adipocyte size in the diet plus exercise groups were significantly different from that of the diet group. Gluteal adipocyte size decreased similarly in all three groups.

CONCLUSION

Addition of exercise training to dietary weight loss preferentially reduces subcutaneous abdominal adipocyte size in obese women. This may be of importance for the treatment of health complications associated with subcutaneous abdominal adiposity.

Insulin-like growth factor-I and insulin are associated with the presence and advancement of adenomatous polyps

BACKGROUND & AIMS

Insulin and insulin-like growth factor-I (IGF-I) affect proliferation, differentiation, and apoptosis and are potential risk factors for colorectal cancer (CRC). Visceral obesity, possibly via hyperinsulinemia, has also been linked to CRC risk. We evaluated the relationship of insulin, IGF-I, insulin-like growth factor binding protein (IGFBP) 3, and visceral adipose tissue (VAT) in subjects with adenomatous polyps, the precursor lesion of colorectal cancer.

METHODS

Participants were asymptomatic subjects who underwent screening flexible sigmoidoscopy (FSG) within the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Subjects underwent single-slice, computerized tomography scanning to measure VAT and serum fasting insulin, IGF-I, and IGFBP-3 measurements.

RESULTS

Four hundred fifty-eight subjects were enrolled, of which 202 subjects had an adenoma, 70 of which were an advanced adenoma. IGF-I (P = .02), IGF-I/IGFBP-3 ratio (P = .003), and insulin (P = .02) were significantly increased in subjects with adenomas compared with controls. In an unadjusted logistic regression analysis using sex-specific quartile cut points, subjects in quartile 4 in comparison with quartile 1 of IGF-I (odds ratio [OR] = 1.7; [95% CI: 1.0-2.9], Ptrend = .03), IGF-I/IGFBP-3 ratio (OR = 1.9 [95% CI: 1.1-3.3], Ptrend = .01), and insulin (OR = 2.1 [95% CI: 1.2-3.6], Ptrend = .04) were at increased risk of adenoma. When limiting the case group to advanced adenomas, the effect was more pronounced: IGF-I (OR = 2.8 [95% CI: 1.3-6.2], Ptrend = .006), IGF-I/IGFBP-3 ratio (OR = 2.3, [95% CI: 1.0-5.2], Ptrend = .04), and insulin (OR = 2.3 [95% CI: 1.1-4.9], Ptrend = .14). Visceral adipose tissue was not associated with adenoma risk.

CONCLUSIONS

Levels of IGF-I, ratio of IGF-I/IGFBP-3, and insulin are associated with adenomas and even more so with advanced adenomas. These data support the hypothesis that insulin and IGF-I may contribute to the development and advancement of adenomatous polyps.

Effects of aerobic exercise and obesity phenotype on abdominal fat reduction in response to weight loss

OBJECTIVE

To test the effects on abdominal fat reduction of adding aerobic exercise training to a diet program and obesity phenotype in response to weight loss.

DESIGN

A prospective clinical trial with a 14-week weight-loss intervention design.

SETTING AND PARTICIPANTS

In total, 209 overweight and obese women were assigned to four subgroups depending on type of treatment and the subject's obesity phenotype: diet alone (DA) with intra-abdominal fat (IF) obesity (> or =mean IF area), diet plus exercise (DE) with IF obesity, DA with abdominal subcutaneous fat (ASF) obesity (<mean IF area) and DE with ASF obesity. Abdominal fat areas were evaluated by CT scans, with values adjusted for selected variables.

RESULTS

Values were adjusted for age, menopausal status and change in body weight and total fat mass. The IF reductions were significantly (P<0.0001) greater in subjects with IF obesity phenotype (-45.1 cm2) compared to the ASF obesity phenotype (-22.2 cm2). The ASF reductions were significantly (P<0.001) greater for subjects with ASF obesity (-74.5 cm2) compared to IF obesity (-55.5 cm2). For IF obesity, the IF reduction was significantly (P<0.01) greater in the DE group (-49.3 cm2) than in the DA group (-37.8 cm2).

CONCLUSION

These results suggest that for individuals with IF obesity, the efficacy on reducing IF of adding aerobic exercise training to a diet-alone weight-reduction program is more prominent (-49.3 cm2/-37.8 cm2=1.3 times) compared with DA. Moreover, abdominal fat reduction was found to be modified by obesity phenotype in response to weight loss.

Physical activity and the risk of ovarian cancer: A case-control study in Canada

We evaluated the impact of recreational and occupational physical activity on ovarian cancer risk using data from a population-based case-control study of 442 cases with histologically confirmed incident ovarian cancer and 2,135 controls aged 20-76 years, conducted in 1994-1997 in Canada. Frequency and intensity of physical activity were collected through self-administered questionnaires. Compared to women in the lowest tertiles of moderate, vigorous and total recreational activity, those in the highest tertiles had multivariable-adjusted odds ratios (and 95% confidence intervals) of 0.67 (0.50-0.88), 0.93 (0.70-1.24) and 0.73 (0.58-0.98), respectively. There were statistically significant trends of decreasing risk with increasing levels of moderate and total recreational activity, with similar patterns for premenopausal and postmenopausal women. A significant reduction in risk associated with higher level of moderate recreational activity was observed for serous, endometrioid and other but not mucinous types of tumors. The analyses in one province with the largest number of cases and controls indicated that occupational activity was associated with reduced ovarian cancer risk by lifetime activity and by various life periods (early 20s, early 30s, early 50s and 2 years before interview). Our study suggests that occupational and regular moderate recreational physical activity reduce ovarian cancer risk.

Effectiveness of weight loss and maintenance interventions in women

Overweight and obesity in women contribute to increased risk of many health problems, including type 2 diabetes. A systematic review of the weight loss literature found 17 articles in which women were the sole subjects and studies were a minimum of 1 year or longer in duration. Data were pooled and average weight loss and maintenance for women at 6 and 12 months was determined for each of the six interventions. Diet as the primary intervention resulted in a weight loss of approximately 7 kg at 6 months (approximately 13% of their initial weight), which was maintained to 12 months. When specific goals for physical activity or weight loss medications were combined with diet, better outcomes were experienced. Regardless of the intervention, at approximately 6 months a weight loss plateau occurred. All of the studies included at least monthly follow-up.

Position of the American Dietetic Association and Dietitians of Canada: Nutrition and Women’s Health

It is the position of the American Dietetic Association (ADA) and Dietitians of Canada (DC) that women have specific nutritional needs and vulnerabilities and, as such, are at unique risk for various nutrition-related diseases and conditions. Therefore, the ADA and the DC strongly support research, health promotion activities, health services, and advocacy efforts that will enable women to adopt desirable nutrition practices for optimal health. Women are at risk for numerous chronic diseases and conditions that affect the duration and quality of their lives. Although women's health-related issues are multifaceted, nutrition has been shown to influence significantly the risk of chronic disease and to assist in maintaining optimal health status. Dietetics professionals strongly support research, health promotion activities, health services, and advocacy efforts that will enable women to adopt desirable nutrition practices for optimal health.

L’activité physique comme moyen de traitement du diabète de type 2 : le rationnel

Physical exercise is an important component of type 2 diabetes mellitus management. Acute physical exercise, on a day by day basis, has a clear hypoglycaemic effect. Physical exercise, on a regular basis at a sufficient level, has numerous favourable effects: improvement of glycaemic control (HbA1c) and insulin sensitivity, decrease of visceral fat mass, increase of skeletal muscle mass, favourable effects on various cardiovascular risk factors (arterial pressure, HDL-cholesterol, triglycerides, etc.). However, precise characteristics of physical exercise to be advised in type 2 diabetic patients (type of exercise, frequency, intensity, etc.) are still a matter of debates, as well as lack of practical guidance in/or differences between the various current recommendations. The crucial point, however, remains their feasibility, as well as the lack of long term patient's motivation and compliance which may partly explain the current low level of physical exercise observed in type 2 diabetic patients.