Ottavio Bosello

Health consequences of obesity in the elderly: a review of four unresolved questions

Obesity prevalence is growing progressively even among older age groups. Controversy exists about the potential harms of obesity in the elderly. Debate persists about the relation between obesity in old age and total or disease-specific mortality, the definition of obesity in the elderly, its clinical relevance, and about the need for its treatment. Knowledge of age-related body composition and fat distribution changes will help us to better understand the relationships between obesity, morbidity and mortality in the elderly. Review of the literature supports that central fat and relative loss of fat-free mass may become relatively more important than BMI in determining the health risk associated with obesity in older ages. Weight gain or fat redistribution in older age may still confer adverse health risks (for earlier mortality, comorbidities conferring independent adverse health risks, or for functional decline). Evaluation of comorbidity and weight history should be performed in the elderly in order to generate a comprehensive assessment of the potential adverse health effects of overweight or obesity. The risks of obesity in the elderly have been underestimated by a number of confounders such as survival effect, competing mortalities, relatively shortened life expectancy in older persons, smoking, weight change and unintentional weight loss. Identification of elderly subjects with sarcopenic obesity is probably clinically relevant, but the definition of sarcopenic obesity, the benefits of its clinical identification, as well as its relation to clinical consequences require further study. Studies on the effect of voluntary weight loss in the elderly are scarce, but they suggest that even small amounts of weight loss (between 5–10% of initial body weight) may be beneficial. In older as well as in younger adults, voluntary weight loss may help to prevent the adverse health consequences of obesity.

Physical disability and muscular strength in relation to obesity and different body composition indexes in a sample of healthy elderly women

OBJECTIVES: The aim of the present study was to test the association between muscular strength, functional limitations, body composition measurements and indexes of sarcopenia in a sample of community-dwelling, elderly women at the high end of the functional spectrum.DESIGN: Cross-sectional.SUBJECTS: In all, 167 women aged 67–78 y were selected from the general population in central Verona. A group of 120 premenopausal healthy women aged 20–50 y represented the young reference group.MEASUREMENTS: Body weight, height, body mass index (BMI) and the presence of acute and chronic conditions were evaluated in each subject. Body composition was measured by dual-energy X-ray absorptiometry (DXA). Physical functioning was assessed using a modified version of the Activities of Daily Living Scale. Dominant leg isometric strength was measured with a Spark Handheld Dynamometer.RESULTS: Elderly women with BMI higher than 30 kg/m2 and in the highest quintile of body fat percent showed a significantly higher prevalence of functional limitation. In our population study, about 40% of sarcopenic elderly women and 50% of elderly women with high body fat and normal muscle mass were functionally limited. The prevalence of functional limitation significantly increased in subjects with class II sarcopenia, defined according to the skeletal muscle mass index (SMI=skeletal muscle mass/body mass × 100). In logistic regression models, after adjusting for age and different chronic health conditions, subjects with BMI higher than 30 kg/m2, in the highest quintile of body fat, or with high body fat and normal muscle mass or class II sarcopenia according to SMI, had a 3–4 times increased risk of functional limitations. Finally, isometric leg strength was significantly lower in subjects in the lowest quintile of relative muscle mass and in sarcopenic and sarcopenic obese women.CONCLUSIONS: High body fat and high BMI values were associated with a greater probability of functional limitation in a population of elderly women at the high end of the functional spectrum. Among the different indexes of sarcopenia used in this study, only SMI predicted functional impairment and disability. Isometric leg strength was significantly lower in subjects with sarcopenia and sarcopenic obesity.

Body fat distribution predicts the degree of endothelial dysfunction in uncomplicated obesity.

OBJECTIVE: To ascertain in obesity the role of body fat distribution (the strongest predictor of morbility and mortality in obese subjects) in determining the degree of endothelial dysfunction, an early marker of atherosclerotic disease.SUBJECTS: 18 premenopausal women with uncomplicated obesity excluding other cardiovascular risk factors and 12 age-matched slim healthy women.MEASUREMENTS: Endothelium-dependent vasodilation, studied as diameter variation in response to an increase in shear-stress, was evaluated in the right common femoral artery of obese and slim subjects by a non invasive approach and compared to glyceril-trinitrate vasodilation. To characterize better the vascular functional and/or structural properties, we studied the arterial wall distensibility by an echo-tracking system. Adipose tissue regional distribution was determined by computerised axial tomography.RESULTS: The endothelium-dependent vasodilation was significantly impaired in obese subjects (P<0.005 versus non-obese subjects) while glyceril-trinitrate vasodilation and arterial distensibility were similar in the two groups. In our obese subjects endothelial-dependent vasodilation was inversely correlated to body fat distribution (visceral/subcutaneous adipose tissue ratio: r=− 0.624, P=0.0058). In contrast, metabolic parameters (except C-peptide response during oral glucose tolerance test (OGTT): r=−0.587, P=0.01), blood pressure values and body weight did not correlate with the endothelial function.CONCLUSION: Uncomplicated obesity per se is characterised by an alteration of the endothelial function; the degree of this vascular damage is predicted by body fat distribution independently of body weight and metabolic and other haemodynamic parameters, and correlates with an index of insulin secretion.

Waist circumference and abdominal sagittal diameter as surrogates of body fat distribution in the elderly: their relation with cardiovascular risk factors

OBJECTIVE: To evaluate the relationship between supine sagittal abdominal diameter (SAD) and other indicators of body fat distribution with cardiovascular (CVD) risk factors in the elderly.SUBJECTS: One-hundred and forty-six women aged from 67 to 78 y with a body mass index (BMI) ranging from 18.7 to 50.6 kg/m2 and 83 men aged between 67 and 78 y with BMI ranging from 19.8 to 37.1 kg/m2.MEASUREMENT: Body fat distribution was assessed using anthropometric indicators: waist circumference, SAD, waist-to-hip ratio (WHR), waist-to-height ratio and SAD-to-thigh ratio.RESULTS: In women, there was a negative correlation between HDL-cholesterol and body weight, BMI, waist, SAD, WHR, waist-to-height ratio and SAD-to-thigh ratio. A significant association was found between triglycerides, basal glucose, 2 h glucose during oral glucose tolerance test (OGTT), systolic blood pressure (SBP), diastolic blood pressure (DBP) and anthropometric variables. In men a negative correlation was found between HDL-cholesterol and all the anthropometric variables. A significant association was found between triglycerides, DBP and body weight, BMI, waist, SAD and waist-to-height ratio. In women, after adjusting for age and BMI, a significant correlation was observed between waist and HDL-cholesterol, triglycerides and basal glucose. This was also seen with SAD and SAD-to-thigh ratio and triglycerides, basal and 2 h glucose. In men, after adjusting for age and BMI a significant correlation was found between SAD and HDL-cholesterol and triglycerides. When adjustments were made for age and waist, the correlations between BMI and metabolic variables as well between BMI and SBP and DBP were no longer significant.CONCLUSIONS: Our study shows that indicators of body fat distribution are associated with CVD risk factors in the elderly independently of BMI. Our data also show that waist and SAD are the anthropometric indicators of fat distribution which are most closely related to CVD risk factors in old age.

Nuts and plasma lipids : An almond-based diet lowers LDL-C while preserving HDL-C

OBJECTIVE To compare lipid-altering effects of an almond-based diet with an olive oil-based diet, against a cheese and butter-based control diet. METHODS Forty-five free-living hyperlipidemic men (n = 12) and women (n = 33) with a mean plasma total cholesterol (TC) of 251 +/- 30 mg/dL followed one of three diets; almond-based, olive oil-based, or dairy-based for 4 weeks. Total fat in each diet was matched, and the study-provided sources of fat comprised the major portion of fat intake. RESULTS Reductions in TC and low-density lipoprotein-cholesterol (LDL-C) between the three groups were significantly different from the almond group (both p < 0.001). Within group analysis revealed that the almond-based diet induced significant reductions in TC (p < 0.05), LDL-C (p < 0.001), and the TC:HDL ratio (p < 0.001), while HDL-C levels were preserved. TC and HDL-C in the control diet were significantly increased from baseline (both p < 0.05), while the olive oil-based diet resulted in no significant changes over the study period. Weight did not change significantly. CONCLUSION Results suggest that the more favorable lipid-altering effects induced by the almond group may be due to interactive or additive effects of the numerous bioactive constituents found in almonds.

Sagittal abdominal diameter as a practical predictor of visceral fat

OBJECTIVE: To evaluate the relationships between the supine sagittal abdominal diameter (SAD) and visceral fat, as well as to evaluate intra- and inter-observer reliability of sagittal diameter measurement.PATIENTS: Twenty-eight women ranging in age from 27–78 y with a body mass index (BMI) ranging from 16.9–48.1 kg/m2 and 23 men ranging in age from 32–75 y with BMI ranging from 20–41.6 kg/m2.MEASUREMENT: Body fat distribution was measured by waist circumference, waist to hip ratio (WHR), SAD, anthropometrically assessed and a single slice of computed tomography (CT) at the L4-L5 level.RESULTS: In both genders, a significant association was found between visceral adipose tissue (AT) and SAD, as evaluated by CT (women r=0.80; men r=0.83, P<0.001), and SAD by anthropometry (women r=0.76; men r=0.82, P<0.001), as well as between visceral AT and waist circumference (women r=0.76, men r=0.86, P<0.001) and WHR (women r=0.57, P<0.01, men r=0.80, P<0.001). A significant association was also found between subcutaneous AT and SAD by anthropometry (women r=0.79, men r=0.74, P<0.001). After adjusting for BMI, the association between subcutaneous AT and SAD was no longer significant in men and only moderately significant in women (r=0.42, P<0.05), while the association between visceral AT and SAD by anthropometry remained significant in both genders (women r=0.63, P<0.001; men r=0.66, P<0.001). When the subjects were divided into two groups according to BMI (lean to moderately overweight women with BMI<28 and men with BMI<30 and obese women with BMI>28 and men with BMI >30) we found that the relationships between SAD by anthropometry, as well as SAD by CT and visceral AT, were higher in lean to moderately overweight subjects than in those who were obese. High inter-observer correlation was found concerning SAD measurement (r=0.99, P<0.001). Intra- and inter-observer precision as evaluated by coefficient of variation and intraclass correlation coefficient for SAD measurement was very high.CONCLUSION: Our study shows the usefulness of SAD by anthropometry to predict visceral fat and its very high inter- and intra-observer precision.

Body composition changes in stable-weight elderly subjects: the effect of sex.

Background and aims: Although cross-sectional and longitudinal studies have shown age-related changes in body composition and fat distribution, they may be related to body weight changes. The aim of this study was to evaluate yearly age-related changes in body composition and fat distribution, over a two-year period, in 101 women and 60 men (age range: 68 to 78 years at baseline). Methods: Body composition was evaluated by dual energy X-ray absorptiometry (DXA), and fat distribution by waist and hip circumferences and waist-to-hip circumference ratio. Baseline free testosterone, IGF-1 and serum albumin were evaluated in all subjects, as well as physical activity. Clinical evaluation was performed at baseline and yearly in order to exclude subjects with any condition inducing pathological changes in body composition or fat distribution. Subjects with a weight change >5% of their baseline body weight during the study period, were excluded. Results: Significant increases occurred in Body Mass Index (BMI) (1.18% in women, 1.13% in men), waist (1.75% in women, 1.39% in men), and hip circumference (1.06% in women, 1.31% in men), whereas height decreased significantly in both men (0A2%) and women (0.55%). Significant increases in total body fat (1.31%) and percent body fat (1.27%) were observed in women but not in men. Lean body mass did not change significantly throughout the study in either sex. Significant losses in leg muscle mass and appendicular skeletal muscle mass (ASM), calculated as the sum of arm and leg fat-free soft tissue, were observed in men (respectively 3.56 and 2.77%) and women (respectively 2A1 and 1.59%). A significant decrease in ASM adjusted by stature (ASM/height2), a proposed proxy for sarcopenia, was found in men only (1.97%). The rates of loss in leg muscle mass and appendicular muscle mass were significantly higher in men than in women, even after adjusting for free testosterone, IGF-1, physical activity and serum albumin. Conclusions: These data demonstrate significant changes in body composition and fat distribution in independently living, weight-stable elderly men and women. These changes are dependent on sex and independent of physical activity, hormones or serum albumin.

The relationship between body composition and physical performance in older women.

BACKGROUND: The relationship between age‐associated change in body composition and physical disability is still unknown. Skeletal muscle mass declines with age in both sexes; however, since women have less muscle mass per unit of weight than men, these changes may be more debilitating in women.

Relation of body fat distribution in men and degree of coronary narrowings in coronary artery disease

This study evaluates the relation between body fat distribution and severity of coronary artery disease (CAD). The study sample comprised 33 patients with angiographically demonstrated CAD and 10 angiographically normal control subjects. Body fat distribution was estimated by computed tomography and degree of coronary narrowings by angiographic score. Body weight, body mass index and total and subcutaneous abdominal adipose tissue areas showed no statistical differences in the 2 groups; visceral abdominal adipose tissue area and the visceral to subcutaneous abdominal adipose tissue area ratio were significantly higher in patients with CAD (p < 0.05). There was a significant correlation between visceral fat and triglycerides, apoprotein B and sum of glucose and insulin during glucose oral tolerance test. Sum of insulin during glucose oral tolerance test, visceral abdominal adipose tissue area and visceral/subcutaneous abdominal adipose tissue area ratio correlated significantly with severity of CAD, as evaluated by coronary score in all subjects and in CAD patients alone. Stepwise multiple regression analysis using the coronary score as the dependent variable and anthropometric and metabolic parameters as independent variables shows that in all subjects and in CAD patients alone, visceral/subcutaneous abdominal adipose-tissue area ratio entered the regression first and the sum of insulin during glucose oral tolerance test second. The results suggest that visceral abdominal adipose tissue area and visceral to subcutaneous abdominal adipose tissue area ratio may be cardiovascular risk factors.

Interrelationships between weight loss, body fat distribution and sex hormones in pre‐ and postmenopausal obese women

Objectives. Relationships between regional body fat distribution and sex hormones as well as changes in sex hormones after weight loss were evaluated.