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result(s) for
"Srikanthan, Preethi"
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Relation of Muscle Mass and Fat Mass to Cardiovascular Disease Mortality
by
Horwich, Tamara B.
,
Tseng, Chi Hong
,
Srikanthan, Preethi
in
Absorptiometry, Photon - methods
,
Adipose Tissue - diagnostic imaging
,
Body composition
2016
We evaluated the relation between components of body composition and mortality in patients with cardiovascular disease (CVD). Dual x-ray absorptiometry body composition data from the National Health and Nutrition Examination Survey 1999 to 2004 was linked to total and CVD mortality data 1999 to 2006 in 6,451 patients with CVD. Kaplan-Meier survival analysis for the end points of total and CVD mortality was plotted by quartiles of muscle mass, fat mass, and categories of body mass index (BMI). Subjects were stratified into 4 groups (low muscle/low fat mass, low muscle/high fat mass, high muscle/low fat mass, and high muscle/high fat mass). Adjusted Cox proportional hazards regression determined hazard ratios for total and CVD mortality. Rates of cardiovascular/total mortality were lower in higher quartiles of muscle mass, fat mass, and higher categories of BMI (p <0.001). The high muscle/low fat mass group had a lower risk of CVD and total mortality (risk-adjusted hazard ratios of 0.32, 95% confidence interval 0.14 to 0.73 and 0.38, 95% confidence interval 0.22 to 0.68, for CVD and total mortality, respectively). Thus, increasing fat mass, muscle mass, and BMI were all correlated with improved survival. The specific subgroup of high muscle and low fat mass had the lowest mortality risk compared with other body composition subtypes. This suggests the importance of body composition assessment in the prediction of cardiovascular and total mortality in patients with CVD.
Journal Article
Sarcopenia Exacerbates Obesity-Associated Insulin Resistance and Dysglycemia: Findings from the National Health and Nutrition Examination Survey III
2010
Sarcopenia often co-exists with obesity, and may have additive effects on insulin resistance. Sarcopenic obese individuals could be at increased risk for type 2 diabetes. We performed a study to determine whether sarcopenia is associated with impairment in insulin sensitivity and glucose homeostasis in obese and non-obese individuals.
We performed a cross-sectional analysis of National Health and Nutrition Examination Survey III data utilizing subjects of 20 years or older, non-pregnant (N = 14,528). Sarcopenia was identified from bioelectrical impedance measurement of muscle mass. Obesity was identified from body mass index. Outcomes were homeostasis model assessment of insulin resistance (HOMA IR), glycosylated hemoglobin level (HbA1C), and prevalence of pre-diabetes (6.0≤ HbA1C<6.5 and not on medication) and type 2 diabetes. Covariates in multiple regression were age, educational level, ethnicity and sex.
Sarcopenia was associated with insulin resistance in non-obese (HOMA IR ratio 1.39, 95% confidence interval (CI) 1.26 to 1.52) and obese individuals (HOMA-IR ratio 1.16, 95% CI 1.12 to 1.18). Sarcopenia was associated with dysglycemia in obese individuals (HbA1C ratio 1.021, 95% CI 1.011 to 1.043) but not in non-obese individuals. Associations were stronger in those under 60 years of age. We acknowledge that the cross-sectional study design limits our ability to draw causal inferences.
Sarcopenia, independent of obesity, is associated with adverse glucose metabolism, and the association is strongest in individuals under 60 years of age, which suggests that low muscle mass may be an early predictor of diabetes susceptibility. Given the increasing prevalence of obesity, further research is urgently needed to develop interventions to prevent sarcopenic obesity and its metabolic consequences.
Journal Article
An obesity paradox in acute heart failure : Analysis of body mass index and inhospital mortality for 108927 patients in the Acute Decompensated Heart Failure National registry
by
FONAROW, Gregg C
,
LOPATIN, Margarita
,
COSTANZO, Maria Rosa
in
Biological and medical sciences
,
Body mass index
,
Cardiology. Vascular system
2007
Background Prior studies on chronic systolic heart failure (HF) have demonstrated that body mass index (BMI) is inversely associated with mortality, the so-called obesity paradox. The aim of this study was to determine whether BMI influences the mortality risk in acute decompensated HF, a subject not previously studied. Methods The Acute Decompensated Heart Failure National Registry was analyzed for acute HF hospitalizations in 263 hospitals in the United States from October 2001 through December 2004. Patients with documented height and weight were divided into BMI (measured in kilograms per square meter) quartiles. Inhospital mortality by BMI quartile for all the patients and for those with reduced (n = 43255) and preserved (n = 37901) systolic function was assessed. Results Body mass index quartiles in the 108927 hospitalizations were QI (16.0-23.6 kg/m2), QII (23.7-27.7 kg/m2), QIII (27.8-33.3 kg/m2), and QIV (33.4-60.0 kg/m2). Patients in the higher BMI quartiles were younger, had more diabetes, and had a higher left ventricular ejection fraction. Inhospital mortality rates decreased in a near-linear fashion across successively higher BMI quartiles. After adjustments for age, sex, blood urea nitrogen, blood pressure, creatinine, sodium, heart rate, and dyspnea at rest, BMI quartile still predicted mortality risk. For every 5-U increase in BMI, the odds of risk-adjusted mortality was 10% lower (95% CI 0.88-0.93,P< .0001). Conclusions In this cohort of hospitalized patients with HF, higher BMI was associated with lower inhospital mortality risk. The relationship between BMI and adverse outcomes in HF appears to be complex and deserving of further study.
Journal Article
An obesity paradox in acute heart failure: Analysis of body mass index and inhospital mortality for 108 927 patients in the Acute Decompensated Heart Failure National Registry
by
Srikanthan, Preethi
,
Costanzo, Maria Rosa
,
Lopatin, Margarita
in
Aged
,
Aged, 80 and over
,
Area Under Curve
2007
Prior studies on chronic systolic heart failure (HF) have demonstrated that body mass index (BMI) is inversely associated with mortality, the so-called obesity paradox. The aim of this study was to determine whether BMI influences the mortality risk in acute decompensated HF, a subject not previously studied.
The Acute Decompensated Heart Failure National Registry was analyzed for acute HF hospitalizations in 263 hospitals in the United States from October 2001 through December 2004. Patients with documented height and weight were divided into BMI (measured in kilograms per square meter) quartiles. Inhospital mortality by BMI quartile for all the patients and for those with reduced (n = 43
255) and preserved (n = 37
901) systolic function was assessed.
Body mass index quartiles in the 108
927 hospitalizations were QI (16.0-23.6 kg/m
2), QII (23.7-27.7 kg/m
2), QIII (27.8-33.3 kg/m
2), and QIV (33.4-60.0 kg/m
2). Patients in the higher BMI quartiles were younger, had more diabetes, and had a higher left ventricular ejection fraction. Inhospital mortality rates decreased in a near-linear fashion across successively higher BMI quartiles. After adjustments for age, sex, blood urea nitrogen, blood pressure, creatinine, sodium, heart rate, and dyspnea at rest, BMI quartile still predicted mortality risk. For every 5-U increase in BMI, the odds of risk-adjusted mortality was 10% lower (95% CI 0.88-0.93,
P < .0001).
In this cohort of hospitalized patients with HF, higher BMI was associated with lower inhospital mortality risk. The relationship between BMI and adverse outcomes in HF appears to be complex and deserving of further study.
Journal Article
Relation of Stress Hormones (Urinary Catecholamines/Cortisol) to Coronary Artery Calcium in Men Versus Women (from the Multi-Ethnic Study of Atherosclerosis MESA)
by
Watson, Karol
,
Horwich, Tamara B.
,
McClelland, Robyn
in
Acidification
,
Antidepressants
,
Arteriosclerosis
2017
The relation between high levels of psychosocial stress and the development of coronary artery disease (CAD) has been increasingly recognized, especially in women. We hypothesized that simple biomarkers of stress, urinary catecholamines/cortisol levels, are associated with more coronary artery calcium (CAC), an indicator of CAD, and that this relation is stronger in women compared with men. Using data from the Multi-Ethnic Study of Atherosclerosis Stress study, we examined the relation between urinary catecholamines/cortisol and CAC. The study cohort (n = 654) was 53% women, and 56.4% of the cohort had detectable CAC. Multivariable regression analyses assessed the relation between urinary catecholamines/cortisol and CAC (odds CAC >0 through logistic and ln CAC through Tobit model). There was an association between increased cortisol and increased CAC and an inverse association between dopamine and CAC. These relations were seen in men and women, with no difference between the genders. In conclusion, higher cortisol and lower dopamine levels are independently associated with higher CAC to a similar degree in men and women. These simple urinary biomarkers contribute to our understanding of the role of stress in the pathogenesis of CAD and may be incorporated into future strategies to prevent and treat CAD.
Journal Article
Sympathetic innervation of the supraclavicular brown adipose tissue: A detailed anatomical study
by
Beyer, Ryan S.
,
Chang, Grace
,
Mori, Shumpei
in
Adipose tissue
,
Adipose tissue (brown)
,
Adipose Tissue, Brown - metabolism
2023
The supraclavicular fossa is the dominant location for human brown adipose tissue (BAT). Activation of BAT promotes non-shivering thermogenesis by utilization of glucose and free fatty acids and has been the focus of pharmacological and non-pharmacological approaches for modulation in order to improve body weight and glucose homeostasis. Sympathetic neural control of supraclavicular BAT has received much attention, but its innervation has not been extensively investigated in humans.
Dissection of the cervical region in human cadavers was performed to find the distribution of sympathetic nerve branches to supraclavicular fat pad. Furthermore, proximal segments of the 4th cervical nerve were evaluated histologically to assess its sympathetic components.
Nerve branches terminating in supraclavicular fat pad were identified in all dissections, including those from the 3rd and 4th cervical nerves and from the cervical sympathetic plexus. Histology of the proximal segments of the 4th cervical nerves confirmed tyrosine hydroxylase positive thin nerve fibers in all fascicles with either a scattered or clustered distribution pattern. The scattered pattern was more predominant than the clustered pattern (80% vs. 20%) across cadavers. These sympathetic nerve fibers occupied only 2.48% of the nerve cross sectional area on average.
Human sympathetic nerves use multiple pathways to innervate the supraclavicular fat pad. The present finding serves as a framework for future clinical approaches to activate human BAT in the supraclavicular region.
Journal Article
Longitudinal associations of insulin resistance with change in bone mineral density in midlife women
by
Karlamangla, Arun S.
,
Cauley, Jane A.
,
Greendale, Gail A.
in
Aging
,
Bone biology
,
Bone density
2022
BACKGROUND. The effects of insulin resistance on bone mineral density (BMD) are unclear.METHODS. In Study of Women’s Health Across the Nation (SWAN) participants, we used multivariable regression to test average insulin resistance (homeostatic model assessment of insulin resistance, HOMA-IR) and rate of change in insulin resistance as predictors of rate of change in lumbar spine (LS) and femoral neck (FN) BMD in 3 stages: premenopause (n = 861), menopause transition (MT) (n = 571), and postmenopause (n = 693). Models controlled for age, average BW, change in BW, cigarette use, race and ethnicity, and study site.RESULTS. The relation between HOMA-IR and BMD decline was biphasic. When average log2HOMA-IR was less than 1.5, greater HOMA-IR was associated with slower BMD decline; i.e., each doubling of average HOMA-IR in premenopause was associated with a 0.0032 (P = 0.01, LS) and 0.0041 (P = 0.004, FN) g/cm2 per year slower BMD loss. When greater than or equal to 1.5, average log2HOMA-IR was not associated with BMD change. In women in whom HOMA-IR decreased in premenopause, the association between the HOMA-IR change rate and BMD change rate was positive; i.e, slower HOMA-IR decline was associated with slower BMD loss. In women in whom insulin resistance increased in premenopause, the association was negative; i.e, faster HOMA-IR rise was associated with faster BMD decline. Associations of average HOMA-IR and HOMA-IR change rate with BMD change rate were similar in postmenopause, but weaker during the MT.CONCLUSION. When it decreases, insulin resistance is associated with BMD preservation; when it increases, insulin resistance is associated with BMD loss.FUNDING. The SWAN has grant support from the NIH of the Department of Health and Human Services (DHHS) through the NIH National Institute on Aging (NIA), National Institute of Nursing Research (NINR), and Office of Research on Women’s Health (ORWH) (grants U01NR004061, U01AG012505, U01AG012535, U01AG012531, U01AG012539, U01AG012546, U01AG012553, U01AG012554, U01AG012495, and U19AG063720).
Journal Article
Associations Between Visceral Fat, Abdominal Muscle, and Coronary Artery Calcification: A Cross-Sectional Analysis of the Multi-Ethnic Study of Atherosclerosis
by
Watson, Karol
,
Srikanthan, Preethi
,
Horwich, Tamara
in
Abdomen
,
abdominal muscle
,
Abdominal Muscles - diagnostic imaging
2024
•Excess adipose tissue is associated with an increased incidence of cardiovascular disease (CVD) risk factors and increased risk for CVD.•Coronary artery calcification is a useful predictor for assessing CVD risk and is associated with major adverse cardiovascular events.•Greater visceral fat area and higher lipid density of abdominal visceral fat was associated with an increased likelihood of having coronary artery calcification.
The associations of body composition components, including muscle and adipose tissue, and markers of subclinical coronary artery disease are unclear. We examined the relation between abdominal computed tomography (CT)–derived measures of the area and density of fat and muscle with coronary artery calcification (CAC), using data from the Multi-Ethnic Study of Atherosclerosis (MESA). A total of 1,974 randomly selected MESA participants free of coronary heart disease underwent abdominal CT scans at examinations 2 or 3, with the resulting images interrogated for abdominal body composition. Using 6 cross-sectional slices spanning L2 to L5, the Medical Imaging Processing Analysis and Visualization software was used to determine abdominal muscle and fat composition using appropriate Hounsfield units ranges. CT chest scans were used to obtain CAC scores, calculated using the Agatston method and spatially weighted calcium score. Multivariable linear and logistic regression analyses were performed to assess the relation between abdominal visceral fat and muscle area and density to prevalent CAC. A total of 1,089 participants had a CAC >0, with an average CAC score of 310. In the fully adjusted model, for every 10-cm2 increase in visceral fat area, the likelihood of having a CAC greater than 0 increased by 0.60% (p <0.001). In the minimally adjusted model, abdominal muscle area was significantly associated with CAC >0, which became nonsignificant in the fully adjusted model. For the density of visceral fat, every 1-Hounsfield unit increase (less lipid-dense fat tissue), the likelihood of having a CAC score >0 decreased by 0.29% (p <0.05). No significant relation was observed between density of abdominal muscle and CAC >0. A greater area and higher lipid density of abdominal visceral fat were associated with an increased likelihood of having CAC, whereas there was no significant relation between abdominal muscle area or density and CAC. The quantity and the quality of fat have associations, with an important marker of subclinical atherosclerosis, CAC, and their significance with respect to cardiovascular outcomes, require further evaluation.
Journal Article
Characterization of Intra-myocellular Lipids using 2D Localized Correlated Spectroscopy and Abdominal Fat using MRI in Type 2 Diabetes
2012
A major goal of this pilot study was to quantify intramyocellular lipids (IMCL), extra-myocellular lipids (EMCL), unsaturation index (UI) and metabolites such as creatine (Cr), choline (Ch) and carnosine (Car), in the soleus muscle using two-dimensional (2D) localized correlated spectroscopy (L-COSY). Ten subjects with type 2 diabetes (T2D), controlled by lifestyle management alone, and 9 healthy control subjects, were studied. In T2D patients only, the following measurements were obtained: body mass index (BMI); waist circumference (WC); abdominal visceral and subcutaneous fat quantified using breath-held magnetic resonance imaging (MRI); a fasting blood draw for assessment of glucose, insulin, and estimation of homeostasis model assessment of insulin resistance (HOMA-IR), HbA1c, and high-sensitivity c-reactive protein (hs-CRP). Analysis of the soleus muscle 2D L-COSY spectral data showed significantly elevated IMCL ratios with respect to Cr and decreased IMCL UI in T2D when compared to healthy subjects (P < 0.05). In T2D subjects, Pearson correlation analysis showed a positive correlation of IMCL/Cr with EMCL/Cr (0.679, P < 0.05) and HOMA-IR (0.633, P < 0.05), and a non-significant correlation of visceral and subcutaneous fat with magnetic resonance spectroscopy (MRS) and other metrics. Characterization of muscle IMCL and EMCL ratios, UI, and abdominal fat, may be useful for the noninvasive assessment of the role of altered lipid metabolism in the pathophysiology of T2D, and for assessment of the effects of future therapeutic interventions designed to alter metabolic dysfunction in T2D.
Journal Article
The association of insulin responses and insulin sensitivity with cognition in adults with pre-diabetes: The Diabetes Prevention Program Outcomes Study
by
Golden, Sherita H.
,
Edelstein, Sharon L.
,
Luchsinger, José A.
in
Adult
,
Aged
,
Alzheimer's disease
2024
Dysglycemia is a significant risk factor for cognitive impairment. However, which pathophysiologic determinant(s) of dysglycemia, impaired insulin sensitivity (ISens) or the islet β-cell's response (IResp), contribute to poorer cognitive function, independent of dysglycemia is not established. Among 1052 adults with pre-diabetes from the Diabetes Prevention Program Outcomes Study (DPPOS), we investigated the relationship between IResp, ISens and cognitive function.
IResp was estimated by the insulinogenic index (IGI; pmol/mmol) and ISens as 1/fasting insulin from repeated annual oral glucose tolerance tests. The mean IResp and mean ISens were calculated over approximately 12 years of follow-up. Verbal learning (Spanish-English Verbal Learning Test [SEVLT]) and executive function (Digital Symbol Substitution Test [DSST]) were assessed at the end of the follow-up period. Linear regression models were run for each cognitive outcome and were adjusted for dysglycemia and other factors.
Higher IResp was associated with poorer performance on the DSST (−0.69 points per 100 unit increase in IGI, 95 % CI: −1.37, −0.01). ISens was not associated with DSST, nor were IResp or ISens associated with performance on the SEVLT.
These results suggest that a greater β-cell response in people at high risk for type 2 diabetes is associated with poorer executive function, independent of dysglycemia and ISens.
•Why did we undertake this study?Few studies have investigated the contribution of impaired insulin sensitivity and islet β-cell insulin response to poorer cognitive function, independent of dysglycemia, in people with pre-diabetes.•What is the specific question(s) we wanted to answer?Does insulin sensitivity and/or islet β-cell insulin response relate to worse performance on tests of cognitive function, independent of dysglycemia in adults with long-standing pre-diabetes?•What did we find?Greater β-cell insulin response was associated with poorer executive function in adults with pre-diabetes.•What are the implications of our findings?Pre-diabetes may serve as an early window for intervention to reduce the impact of insulin dysregulation on cognitive dysfunction.
Journal Article