Changes In Intra-abdominal Fat Research Articles

Lower High-Density Lipoprotein Cholesterol Concentration Is Independently Associated with Greater Future Accumulation of Intra-Abdominal Fat.

BackgroundBoth intra-abdominal fat (IAF) and high-density lipoprotein cholesterol (HDL-C) are known to be associated with cardiometabolic health. We evaluated whether the accumulation of computed tomography (CT)-measured IAF over 5 years was related to baseline HDL-C concentration in a prospective cohort study.MethodsAll participants were Japanese-Americans between the ages of 34 and 74 years. Plasma HDL-C concentration and CT measurements of IAF, abdominal subcutaneous fat (SCF), and thigh SCF cross-sectional areas were assessed at baseline and at 5-year follow-up visits.ResultsA total of 397 subjects without diabetes were included. The mean±standard deviation HDL-C concentration was 51.6±13.0 mg/dL in men and 66.0±17.0 mg/dL in women, and the IAF was 91.9±48.4 cm2 in men and 63.1±39.5 cm2 in women. The baseline plasma concentration of HDL-C was inversely associated with the change in IAF over 5 years using multivariable regression analysis with adjustment for age, sex, family history of diabetes, weight change over 5 years, and baseline measurements of body mass index, IAF, abdominal SCF, abdominal circumference, thigh SCF, and homeostatic model assessment for insulin resistance.ConclusionThese results demonstrate that HDL-C concentration significantly predicts future accumulation of IAF over 5 years independent of age, sex, insulin sensitivity, and body composition in Japanese-American men and women without diabetes.

Leptin and Adiponectin Concentrations Independently Predict Future Accumulation of Visceral Fat in Nondiabetic Japanese Americans.

Whether leptin and adiponectin are independently associated with regional body fat distribution was investigated in a prospective study of Japanese Americans. Nondiabetic participants 39 to 79 years of age were followed for 5 years to assess change in body composition. Leptin and adiponectin concentrations were evaluated at baseline and by single-slice computed tomography measurements of intra-abdominal fat (IAF), abdominal subcutaneous fat (SCF), and thigh SCF cross-sectional areas at baseline and at 5 years. Ninety-six men and ninety-five women without diabetes had the following baseline mean (SD) values: age 45.7 (3.5) years and 46.4 (3.9) years, IAF 78.7 (38.6) cm2 and 62.1 (39.0) cm2 , leptin concentration 4.5 (2.3) μg/L and 10.2 (5.2) μg/L, and adiponectin concentration 7.4 (3.2) μg/mL and 10.8 (4.7) μg/mL, respectively. Baseline leptin (β = 1.7722, P = 0.014) and adiponectin concentrations (β = -0.4162, P < 0.001) were significantly associated with IAF change over 5 years in multivariable models adjusting for age, sex, diabetes family history, weight change over 5 years, and baseline measurements of BMI, IAF, abdominal SCF, waist circumference, thigh fat, and homeostatic model assessment of insulin resistance. In nondiabetic Japanese Americans, a higher concentration of leptin was associated with greater accumulation of IAF and a higher concentration of adiponectin with lesser accumulation of IAF over 5 years.

Longitudinal changes in plasma sex hormone concentrations correlate with changes in CT-measured regional adiposity among Japanese American men over 10years.

Ageing in male adults is typically accompanied by adiposity accumulation and changes in circulating sex hormone concentrations. We hypothesized that an ageing-associated increase in oestrogens and decrease in androgens would correlate with an increase in adiposity. 10-year prospective, observational study. A total of 190, community-dwelling men in the Japanese American Community Diabetes Study. At 0 and 10years, CT scanning quantified intra-abdominal fat (IAF) and subcutaneous fat (SCF) areas while plasma concentrations of oestradiol, oestrone, testosterone and dihydrotestosterone were measured by liquid chromatography-tandem-mass spectrometry at each time point. Multivariate linear regression analyses assessed correlations between 10-year changes in hormone concentrations and IAF or SCF, adjusting for age and baseline fat depot area. Participants were middle-aged [median 54.8 years, interquartile range (IQR) 39.9-62.8] men and mostly overweight by Asian criterion (median BMI 24.9, IQR 23.3-27.1) and with few exceptions had normal sex-steroid concentrations. Median oestradiol and dihydrotestosterone did not change significantly between 0 and 10years (P=.084 and P=.596, respectively) while median oestrone increased (P<.001) and testosterone decreased (P<.001). Median IAF and SCF increased from 0 to 10years (both P<.001). In multivariate analyses, change in oestrone positively correlated (P=.019) while change in testosterone (P=.003) and dihydrotestosterone (P=.014) negatively correlated with change in IAF. Plasma oestradiol and oestrone positively correlated with change in SCF (P=.041 and P=.030, respectively) while testosterone (P=.031) negatively correlated in multivariate analysis. Among 190 community-dwelling, Japanese American men, increases in IAF were associated with decreases in plasma androgens and increases in plasma oestrone, but not oestradiol, at 10years. Further research is necessary to understand whether changing hormone concentrations are causally related to changes in regional adiposity or whether the reverse is true.

Dietary Animal and Saturated Fat Predict Future Visceral Fat Accumulation in Japanese Americans

Both diet and visceral adiposity play key roles in cardiometabolic disease. However, the association between dietary fat and subsequent visceral fat accumulation is not known. Thus, we prospectively examined future visceral fat accumulation in relation to dietary intake of animal and plant fats, or saturated and polyunsaturated fats in 312 nondiabetic Japanese-American men and women. Visceral adiposity was measured as intra-abdominal fat (IAF) area at the umbilicus by computed tomography at baseline and 10-11 years. Detailed dietary information was assessed at baseline using a food frequency questionnaire and 24-hour recall. Insulin sensitivity was evaluated by homeostasis model assessment for insulin resistance (HOMA-IR) and insulin response by the insulinogenic index (IGI) [Δinsulin/Δglucose (30-0 minutes)]. After adjustment for baseline IAF, age, sex, smoking habits (non-smokers, past-smokers, current smokers), physical activity, alcohol consumption, HOMA-IR, IGI, total protein intake, and total carbohydrate intake in multiple linear regression models, baseline log transformed animal fat intake [coefficient=15.319 (P=0.002)], but not plant fat intake [0.163 (P=0.270)], was associated with future IAF change. In the model that included saturated and polyunsaturated fat substituted for animal and plant fat intake, saturated fat was associated with future IAF change in both men [0.892 (P=0.030)] and women [1.121 (P=0.022)], but a statistically significant interaction was present between sex and polyunsaturated fat, such that polyunsaturated fat intake was inversely associated with future IAF change in men [-1.290 (P=0.003)], but not women [-0.058 (P=0.905)]. In conclusion, in both men and women, higher intake of animal fat and saturated fat, not plant fat, precede more visceral fat accumulation, while in men only, higher polyunsaturated fat intake precedes less visceral fat accumulation. Disclosure T. Hayashi: None. K. Sato: None. D.L. Leonetti: None. S.E. Kahn: Advisory Panel; Self; Boehringer Ingelheim GmbH, Elcelyx Therapeutics, Inc., Eli Lilly and Company, Intarcia Therapeutics, Inc., Janssen Research &amp; Development, Merck &amp; Co., Inc., Novo Nordisk A/S. S. Uehara: None. W.Y. Fujimoto: None. E.J. Boyko: None.

Natural history of impaired glucose tolerance in Japanese Americans: Change in visceral adiposity is associated with remission from impaired glucose tolerance to normal glucose tolerance

AimsTo describe the roles of intra-abdominal fat and its change in the remission of impaired glucose tolerance (IGT) to normal glucose tolerance (NGT). MethodsWe followed 157 Japanese Americans with IGT at baseline for 10–11 years without external intervention. We measured intra-abdominal and abdominal subcutaneous fat area (IAFA and ASFA) by computed tomography at baseline and at 5–6 years of follow-up. Change in IAFA and ASFA (ΔIAFA and ΔASFA) were calculated by subtracting baseline fat area from 5–6 year follow-up fat area. Glucose and insulin at fasting and during a 75-g oral glucose tolerance test, insulinogenic index (IGI [Δinsulin/Δglucose (30–0 min)]) and homeostasis model assessment for insulin resistance (HOMA-IR) were measured at baseline. ResultsFourty-four subjects remitted to NGT. Among those with lower IAFA (≤median 91.31 cm2) and the lowest tertile of ΔIAFA, 45% remitted, while with higher IAFA (>91.31 cm2) and the highest tertile of ΔIAFA, only 12.5% remitted. ΔIAFA was significantly associated with remission to NGT (multiple-adjusted odd ratio [1-SD decrease] 1.93, 95% CI 1.10–3.36) independent of IAFA, ASFA, ΔASFA, IGI, HOMA-IR, age, sex, and family history of diabetes. ConclusionsIn the natural history of IGT, change in intra-abdominal fat was associated with remission to NGT.

Association between changes in fat distribution and biomarkers for breast cancer.

We assessed the associations between changes in total and abdominal fat and changes in biomarkers for breast cancer risk using data of the SHAPE-2 trial. In the SHAPE-2 trial, 243 postmenopausal overweight women were included. The intervention in this trial consisted of 5-6 kg weight loss either by diet only or exercise plus diet. After 16 weeks, we measured serum sex hormones, inflammatory markers, total body fat (measured by DEXA scan) and intra and subcutaneous abdominal fat (measured by MRI). Associations between changes in different body fat depots and biomarkers were analysed by linear regression using the study cohort irrespective of randomisation to make maximal use of the distribution of changes in fat measures. We found that a loss in total body fat was associated with favourable changes in free oestradiol, free testosterone, leptin and sex hormone binding globulin (SHBG). The loss of intra-abdominal fat was associated with a decrease in free testosterone, hsCRP and leptin, and an increase in SHBG. In the multivariable analysis, the best fitted models for the biomarkers free oestradiol, SHBG leptin and adiponectin included only total body fat. For free testosterone, this was subcutaneous abdominal fat, and for hsCRP and IL-6, only intra-abdominal fat change was important. For IL-6 and adiponectin, however, associations were weak and not significant. We conclude that, in our population of healthy overweight postmenopausal women, loss of fat at different body locations was associated with changes in different types of biomarkers, known to be related to risk of breast cancer.

Change in Intra-Abdominal Fat Predicts the Risk of Hypertension in Japanese Americans.

In Japanese Americans, intra-abdominal fat area measured by computed tomography is positively associated with the prevalence and incidence of hypertension. Evidence in other populations suggests that other fat areas may be protective. We sought to determine whether a change in specific fat depots predicts the development of hypertension. We prospectively followed up 286 subjects (mean age, 49.5 years; 50.4% men) from the Japanese American Community Diabetes Study for 10 years. At baseline, subjects did not have hypertension (defined as blood pressure ≥140/90 mm Hg) and were not taking blood pressure or glucose-lowering medications. Mid-thigh subcutaneous fat area, abdominal subcutaneous fat area, and intra-abdominal fat area were directly measured by computed tomography at baseline and 5 years. Logistic regression was used to estimate odds of incident hypertension over 10 years in relation to a 5-year change in fat area. The relative odds of developing hypertension for a 5-year increase in intra-abdominal fat was 1.74 (95% confidence interval, 1.28-2.37), after adjusting for age, sex, body mass index, baseline intra-abdominal fat, alcohol use, smoking status, and weekly exercise energy expenditure. This relationship remained significant when adjusted for baseline fasting insulin and 2-hour glucose levels or for diabetes mellitus and pre-diabetes mellitus classification. There were no significant associations between baseline and change in thigh or abdominal subcutaneous fat areas and incident hypertension. In conclusion, in this cohort of Japanese Americans, the risk of developing hypertension is related to the accumulation of intra-abdominal fat rather than the accrual of subcutaneous fat in either the thigh or the abdominal areas.

Validation of the measurement of intra-abdominal fat between ultrasound and CT scan in women with obesity and infertility

To compare the means and changes over time of intra-abdominal fat (IAF) and subcutaneous abdominal fat (SAF) measured by abdominal ultrasound (US) and computerized tomography (CT). Prospective cohort study of 53 women with obesity and infertility undergoing a lifestyle program. The Pearson's correlation between IAF measurement by US compared to CT was good at baseline, month 3 and 6 (all r ≥ 0.72). The correlation of SAF measurement by US compared to CT was reasonable at baseline (r = 0.54; 95%CI 0.30-0.78) and weak at month 3 and 6 (all r ≤ 0.39). The correlation between the changes in IAF over 3 and 6 months by US compared to CT was reasonable and significant respectively (all r > 0.48). US could not measure the changes of SAF over time. The Bland-Altman plot showed good agreement between US and CT for IAF measurements (-1.1 [95%CI -3.9-1.6] cm lower mean in US) at baseline. For changes of IAF over time, mean estimates were in agreement. In women with obesity and infertility, measuring IAF by US is in good agreement with the CT scan methodology but the measurement of SAF by US is unreliable.

Effect of extended-release niacin on hormone-sensitive lipase and lipoprotein lipase in patients with HIV-associated lipodystrophy syndrome

HIV-associated lipodystrophy syndrome is strongly associated with antiretroviral treatment in patients with human immunodeficiency virus (HIV). Niacin is thought to affect hormone-sensitive lipase (HSL) and lipoprotein lipase (LPL) expression in peripheral and intra-abdominal fat (IAF). This study investigated the effect of extended-release niacin (ERN) on adipose HSL and LPL expression in patients with HIV-associated lipodystrophy syndrome. Changes in IAF and peripheral fat content and HSL and LPL expression were examined in 4 HIV-infected patients recruited from a prospective study treated with ERN. Patients underwent limited 8 slice computerized tomography abdominal scans, dual-energy X-ray absorptiometry scans, and skin punch biopsies of the mid-thigh at baseline and after 12 weeks of ERN. All subjects were on stable highly active antiretroviral therapy prior to and during the study. Changes in body habitus were self-reported. Normalized HSL expression decreased in 3 patients and normalized LPL expression increased in all 4 patients when comparing pre- and post-ERN treated samples. All subjects showed a decrease in total cholesterol (TC) and triglyceride (TG) levels. Preliminary analysis suggests ERN may induce changes in HSL and LPL expression. This method is a feasible approach to identify changes in adipose RNA expression involved with lipolysis.

Changes in Intra‐abdominal Fat in Early Postmenopausal Women: Effects of Hormone Use

Intra-abdominal fat (IAF) accumulates with age, is greater among postmenopausal vs. premenopausal women, and is linked to risk for both type 2 diabetes and cardiovascular disease. Whether hormone replacement therapy (HRT) prevents or attenuates changes in IAF and related risk factors is not clear. The objectives of this observational study were to 1) determine whether HRT attenuated the expected age-related increase in IAF and 2) identify the independent effects of HRT and fat distribution on changes in disease risk factors. Subjects were early postmenopausal white women 45 to 55 years of age. Women either used HRT at the time of enrollment (n = 33) or did not (n = 17). Subjects were evaluated at baseline and 2 years for body composition (DXA), body fat distribution (computed tomography), insulin sensitivity (Si; minimal model), and serum lipids. IAF increased significantly over 2 years, and this increase was not attenuated by HRT. HRT users had less IAF throughout the study. HRT users showed an increase in Si, whereas non-users showed a decrease. Superficial subcutaneous adipose tissue was significantly and independently related to total cholesterol, whereas IAF was related to high-density lipoprotein cholesterol, triglycerides, and Si. HRT users had less IAF at baseline and throughout the study. Whether HRT altered the relationship between total body fat and IAF or whether differences between groups existed before the study should be addressed through a randomized, interventional study design. HRT had a significant effect on Si; IAF and superficial subcutaneous adipose tissue were significant determinants of disease risk factors.

Effects of a Moderate Intensity Exercise Intervention on Estrogen Metabolism in Postmenopausal Women

Abstract Physical activity has been associated with reduced breast cancer risk, potentially via hormonal pathways, and high urinary excretion of 2-hydroxyestrone (2-OH E1) relative to 16α-hydroxyestrone (16α-OH E1) also has been associated with reduced breast cancer risk. Studies suggest that body composition and exercise can influence estrogen metabolism. We determined the effects of a 12-month moderate intensity aerobic exercise intervention on urinary 2-OH E1, 16α-OH E1, and their ratio in overweight and obese, previously sedentary, postmenopausal women, ages 50–75 years. Women were randomized to a 12-month exercise intervention (n = 87) or stretching control group (n = 86); 170 completed the study. Urinary 2- and 16α-OH E1 were measured in spot urines collected at baseline, 3, and 12 months. Body composition was measured at baseline and 12 months. Differences between exercisers and controls for excretion of estrogen metabolites were determined using general estimating equations. Further analyses assessed change in estrogen metabolites and their ratio by subgroups of change in body composition. Overall, there were no significant effects of the exercise intervention on 2-OH E1, 16α-OH E1, or their ratio (P &amp;gt; 0.05). There appeared to be an effect of change in intra-abdominal fat and adherence to the exercise intervention on change in the estrogen metabolites or their ratio. However, this did not reflect a potentially desirable change in estrogen metabolites associated with the exercise intervention. Thus, this 12-month moderate intensity exercise intervention did not significantly alter urinary excretion of 2-OH E1, 16α-OH E1, or their ratio in this population of women.

Effect of Exercise on Total and Intraabdominal Body Fat in Postmenopausal Women: A Randomized, Controlled Trial

Irwin, Melinda L.; Yasui, Yutaka; Ulrich, Cornelia M.; Bowen, Deborah; Rudolph, Rebecca E.; Schwartz, Robert S.; Yukawa, Michi; Aiello, Erin; Potter, John D.; McTiernan, Anne

Longitudinal assessment of intra-abdominal fat in postmenopausal women.

Longitudinal changes in intra-abdominal (IA) fat and total body fat were assessed in three healthy postmenopausal Caucasian women receiving hormone replacement therapy (HRT) during a seven-year follow-up study. Measurements were made using dual-energy X-ray absorptiometry, anthropometry, and magnetic resonance images. Changes in intra-abdominal fat were examined in relation to different patterns of weight modification. The weight-stable women had the lowest percent body fat and IA fat at all examinations, with a slight decrease in IA fat at follow-up. The person with a gradual gain in weight of 1.9 kg experienced small increases in body fat and IA fat. The weight-cycling woman had the highest weight, percent body fat, and IA fat area at all examinations. The amounts of IA fat and percent body fat fluctuated with body weight fluctuations. Together with other findings, our results suggest that lean, weight-stable individuals receiving HRT can maintain a low level of IA fat, whereas those experiencing weight gains or regaining lost weight have increases in IA fat.

Effects of the menopause transition on body fatness and body fat distribution.

The menopause transition increases cardiovascular and metabolic disease risk, partly because of the adverse effects of estrogen deficiency on the plasma lipid-lipoprotein profile and cardiovascular function. This increased cardiovascular and metabolic disease risk may also be partially mediated by increased body fat, increased intra-abdominal adipose tissue accumulation, or both. The objective of this mini-review is to summarize studies that have investigated the relationships among the menopause transition, body fatness, and body fat distribution. A review of cross-sectional and longitudinal studies on menopause that examined body fatness and body fat distribution. Cross-sectional reports show that the menopause transition is related to modest increases in body mass index or total fatness, although not all studies found significant effects. Increased central adiposity appears to be related to menopause, independent of advancing age, but these results are methodology dependent. An independent effect of menopause on central body fatness was noted by the use of techniques such as DEXA or computed tomography, whereas studies using circumference measures showed discrepant results. Longitudinal studies showed that the menopause transition accelerated the increase in central adiposity, although no studies quantified changes in intra-abdominal fat by imaging techniques. Thus, additional longitudinal studies using more accurate measures of adiposity are needed to critically examine the effects of the menopause transition on total and central body fatness. Collectively, previous studies suggest that menopause is related to modest increase in total fatness and accelerated accumulation of central body fat that exceeds changes normally attributed to the aging process. These changes may increase the risk for cardiovascular and metabolic disease in aging women.

Low Insulin Secretion and High Fasting Insulin and C-Peptide Levels Predict Increased Visceral Adiposity: 5-Year Follow-Up Among Initially Nondiabetic Japanese-American Men

Insulin resistance and hyperinsulinemia occur more frequently in subjects with greater visceral adiposity, but it is not known whether these metabolic abnormalities precede or follow visceral fat accumulation. We prospectively studied the development of visceral adiposity in relation to fasting and stimulated insulin and C-peptide levels. We followed 137 nondiabetic, second-generation Japanese-American men for changes in visceral adiposity over 5 years. Intra-abdominal fat (IAF) area (square centimeters) was measured at the umbilicus by computed tomography at baseline and after 5 years. Plasma insulin and C-peptide levels were measured after an overnight fast and during an oral glucose tolerance test. Beta-cell function was measured by the insulin secretion ratio (30-0 min plasma insulin difference)/(30-0 min plasma glucose difference). After adjustment for baseline IAF in multiple linear regression models, baseline fasting insulin (coefficient = 0.241, P = 0.048) and C-peptide (coefficient = 38.538, P < 0.001) levels were positively correlated, while the baseline insulin secretion ratio was negatively correlated with IAF change (coefficient = -0.099, P = 0.027). With IAF difference coded as a dichotomous variable (> 0 cm2 vs. < or = 0 cm2), the highest versus lowest tertile of baseline fasting insulin (odds ratio [OR] = 3.0, 95% CI 1.0-9.7) and fasting C-peptide (OR = 8.1, 95% CI 2.4-26.8) levels and the lowest versus highest tertile of the insulin secretion ratio (OR = 3.3, 95% CI 1.0-10.0) were associated with higher odds of IAF gain. Greater insulin resistance and reduced insulin secretion precede visceral fat accumulation in nondiabetic Japanese-American men.