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1.
Alzheimers Dement ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39072914

RESUMEN

INTRODUCTION: Amid recent approvals, early Alzheimer's disease (AD) remains an active area of treatment development. METHODS: We performed a conjoint experiment to compare preferences among 26 patients with mild cognitive impairment for four trial features including designs incorporating active aducanumab-control (vs. placebo), returning tau positron emission tomography (PET) results (vs. no disclosure), remote study partner participation (vs. in person), and increased risk of brain swelling (vs. lower risk). We used a generalized estimating equation to model the utility of factor levels. RESULTS: Returning tau PET results had the highest utility (est: 0.47; 95% confidence interval [CI]: 0.13, 0.81; P = 0.007); remote study partner participation showed a similar trend (est: 0.29; 95% CI: -0.05, 0.63; P = 0.097). Trials with active-controlled design (est: 0.01; 95% CI: -0.33, 0.35; P = 0.956) did not demonstrate utility and higher risk of brain swelling had negative utility (est: -0.64; 95% CI: -0.99, -0.30; P < 0.001). DISCUSSION: Returning additional biomarker results may increase willingness to enroll in early AD trials. HIGHLIGHTS: We compared mild cognitive impairment participant preferences for four trial design features. Returning tau positron emission tomography results had the highest utility. Remote study partner participation showed a positive, albeit non-significant, trend. No utility was observed for an active aducanumab-control design.

2.
J Nutr ; 151(1): 245-254, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33245130

RESUMEN

BACKGROUND: Inclusion of dairy in diet patterns has been shown to have mixed effects on weight loss. A prevailing hypothesis is that dairy improves weight loss by influencing endocrine systems associated with satiety and food intake regulation. OBJECTIVES: The objective of the current study was to evaluate the effect of weight loss with or without adequate dietary dairy on subjective and objective appetitive measures. METHODS: Men and women who were habitual low dairy consumers (n = 65, 20-50 y) participated in a 12-wk randomized controlled feeding weight loss trial. During the 12-wk intervention, a low-dairy (<1 serving dairy/d) was compared with an adequate-dairy (3-4 servings dairy/d) diet, both with a 500-kcal deficit/d. Test days, before and at the end of the intervention, began with 2 fasting blood draws and visual analog scale (VAS) measures, followed by a standard breakfast (25% of prescribed restricted calories), 5 postbreakfast blood draws and VASs, a standard lunch (40% of restricted energy amount), and 12 postlunch blood draws and VASs. Blood samples were used for satiety hormone measurements. On a separate day when matching standard meals were consumed, an ad libitum buffet meal was provided as dinner, at a self-selected time. Meal duration and intermeal interval were recorded. RESULTS: Weight loss (-6.1 kg), irrespective of dairy, resulted in reduced fasting insulin (-20%) and leptin (-25%), and increased fasting acylated ghrelin (+25%) and VAS desire to eat (+18%) (P < 0.05). There were no effects of dairy on objective or subjective satiety measures. Weight loss marginally reduced the intermeal interval (289 min compared with 276 min, P = 0.059) between lunch and the ad libitum buffet. CONCLUSIONS: These results do not support the hypothesis that inclusion of dairy in long-term dietary patterns influences appetite during weight loss. Weight loss per se has a modest impact on select systems that regulate hunger and satiety.This trial was registered at clinicaltrials.gov as NCT00858312.


Asunto(s)
Productos Lácteos , Dieta , Tracto Gastrointestinal/metabolismo , Periodo Posprandial , Respuesta de Saciedad , Pérdida de Peso , Adulto , Femenino , Ghrelina/metabolismo , Humanos , Insulina/metabolismo , Leptina/metabolismo , Masculino , Persona de Mediana Edad , Adulto Joven
3.
Alzheimer Dis Assoc Disord ; 35(2): 141-147, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33060367

RESUMEN

INTRODUCTION: The apolipoprotein E (APOE) gene is the strongest known genetic risk factor for sporadic Alzheimer disease (AD). APOE can be used as an enrichment strategy or inclusion criterion for AD prevention trials. Personal genomics companies market direct-to-consumer (DTC) genetic tests, including APOE. We assessed DTC APOE testing usage among enrollees of the University of California Irvine Consent-to-Contact Registry, an online recruitment registry, and attitudes toward using this information in clinical trial recruitment. METHODS: We emailed links to an electronic survey to registry enrollees age 50 years or older. We assessed participants' use of DTC services, willingness to learn APOE status, and willingness to share genetic information. Logistic regression models assessed relationships between DTC testing usage and demographic characteristics, and with willingness to share results to assist trial recruitment. RESULTS: Among 1312 responders (57% response rate), few (7%) had used DTC testing for APOE. Non-Hispanic Asian enrollees were 93% less likely to have used DTC testing, compared with non-Hispanic Whites [95% confidence interval: (0.01, 0.67)]. Willingness to share APOE information for study recruitment was >90% for both users and nonusers. CONCLUSIONS: Matching participants to trials on the basis of DTC APOE information may be an effective way to streamline AD prevention trial recruitment.


Asunto(s)
Enfermedad de Alzheimer/genética , Ensayos Clínicos como Asunto , Pruebas Dirigidas al Consumidor , Pruebas Genéticas , Selección de Paciente , Anciano , Apolipoproteínas E/genética , California , Femenino , Humanos , Difusión de la Información , Masculino , Persona de Mediana Edad , Sistema de Registros , Encuestas y Cuestionarios
4.
J Nutr ; 148(5): 685-692, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29897486

RESUMEN

BACKGROUND: Multiple hormones are involved in the regulation of food intake and glucose metabolism. Past intervention studies showed a benefit of eating breakfast on satiety, but this was possibly confounded by the disruption of habitual meal patterns. OBJECTIVE: The objective of this study was to compare hormonal responses, including insulin, leptin, glucagon-like peptide-1, ghrelin, peptide YY (PYY3-36), and cholecystokinin (CCK), between habitual breakfast eaters (Br-Es) and habitual skippers (Br-Ss) to a standard midday meal. METHODS: Thirty-two women [mean ± SD age: 22.6 ± 3.3 y; body mass index (in kg/m2): 21.8 ± 2.0] participated in a cross-sectional study that consisted of a 3-h test protocol that included a standard test meal served at 1230 with pre- and postmeal blood sampling. The protocol required that Br-Es eat a typical breakfast between 0700 and 1000, whereas Br-Ss had no breakfast meal and had fasted for 12 h. Blood was drawn 35 and 5 min prelunch and 5, 20, 35, 50, and 110 min postlunch. RESULTS: Repeated-measures ANOVA revealed a group difference for PYY3-36 (P = 0.001), with the Br-E group exhibiting 50-90% higher concentrations throughout the test period. Leptin tended to be different (P = 0.08) between groups, with higher mean ± SD values for the Br-S group (27.6 ± 29.6 ng/mL) compared with the Br-E group (11.5 ± 9.8 ng/mL). Partial least squares regression analysis confirmed that these 2 hormones were important contributors to the patterns of the hormones, anthropometric, clinical, and behavioral variables that differed between groups; insulin and CCK were important as well. CONCLUSION: We found differences between the Br-E and Br-S groups in circulating gut and adipose-derived hormones measured midday, indicating that the breakfast habit is associated with the hormonal milieu before and after a midday meal. The different patterns may be short-lived or may impact metabolism later in the day. This report is a secondary analysis of a trial registered at clinicaltrials.gov as NCT01427556.


Asunto(s)
Hormonas/sangre , Comidas/fisiología , Periodo Posprandial/fisiología , Adulto , Glucemia/metabolismo , Desayuno , Colecistoquinina/sangre , Estudios Transversales , Ingestión de Alimentos/fisiología , Ácidos Grasos no Esterificados/sangre , Conducta Alimentaria/fisiología , Femenino , Ghrelina/sangre , Humanos , Insulina/sangre , Leptina/sangre , Almuerzo , Fragmentos de Péptidos/sangre , Péptido YY/sangre , Saciedad/fisiología , Adulto Joven
5.
J Nutr ; 143(1): 46-52, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23190756

RESUMEN

Dairy food enhances weight loss in animal models, possibly by modifying the metabolic effects of cortisol. This study determined in overweight women (ages 20.0-45.9 y; n = 51) whether including dairy food in an energy-restricted diet affects cortisol concentrations and whether differences in provoked cortisol explain the magnitude of weight loss. Women received either an adequate amount of dairy food (AD), the equivalent of ≥711 mL/d milk, or a low amount of dairy food (LD), the equivalent to ≤238 mL/d milk, in a 12-wk, energy-restricted dietary intervention. Participants were tested in a 12-h laboratory visit, which included 2 standard meals and a dinner buffet that was consumed ad libitum. Salivary cortisol was measured from waking to bedtime. Energy restriction increased (P ≤ 0.04) the minimum and decreased (P ≤ 0.02) the diurnal amplitude in the salivary cortisol concentration from baseline to postintervention. Energy restriction enhanced the dinner meal-stimulated salivary cortisol response (DMR) (P ≤ 0.02) but only in the LD group. Compared with the LD treatment, the AD treatment induced (P ≤ 0.04) greater reductions in body weight and fat, but only in women characterized as having a baseline DMR (responders) (n = 26); weight and fat lost in the AD and LD groups were similar in nonresponders (n = 25). Overall, energy restriction dampened diurnal salivary cortisol fluctuations [symptomatic of hypothalamic-pituitary-adrenal (HPA) axis dysfunction] and enhanced dinner meal-stimulated salivary cortisol concentrations. The AD treatment prevented the latter. Furthermore, certain phenotypic markers of HPA axis function may help to expose the weight-reducing effects of consuming dairy food.


Asunto(s)
Productos Lácteos , Dieta Reductora , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisario/fisiopatología , Sobrepeso/dietoterapia , Sistema Hipófiso-Suprarrenal/fisiopatología , Saliva/metabolismo , Adiposidad , Adulto , Biomarcadores/metabolismo , Índice de Masa Corporal , California , Ritmo Circadiano , Dieta Reductora/métodos , Femenino , Humanos , Comidas , Persona de Mediana Edad , Obesidad/dietoterapia , Obesidad/metabolismo , Obesidad/fisiopatología , Sobrepeso/metabolismo , Sobrepeso/fisiopatología , Pérdida de Peso , Adulto Joven
7.
J Alzheimers Dis ; 90(3): 1291-1300, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36245381

RESUMEN

BACKGROUND: Clinical trials now test promising therapies in the preclinical stages of Alzheimer's disease (AD). Participant willingness to enroll in different types of preclinical AD trials is understudied and whether the FDA approval of aducanumab affected these attitudes is unknown. OBJECTIVE: To evaluate preferences toward three preclinical AD trial scenarios and whether the FDA approval of aducanumab changed willingness to participate among potential trial participants. METHODS: Through an electronic survey, we asked enrollees in a recruitment registry age 50-79 to rate their willingness (using a 6-point Likert scale) to enroll in three hypothetical preclinical AD trial scenarios: an in-clinic infused monoclonal antibody intervention, a home-infused monoclonal antibody intervention, and an oral BACE inhibitor intervention. We administered the survey before and after the FDA approval of aducanumab. We used a generalized estimating equation model to assess group differences in preference for the trial scenarios. We used a paired t-test to determine if willingness to participate (using total willingness across three scenarios as the outcome) changed after the FDA decision. RESULTS: At baseline, the mean participant willingness was highest in the in-clinic infusion scenario. There was no significant change in willingness to participate, overall, after the FDA decision. Participants who were independently aware of the FDA's decision (prior to the second survey) demonstrated reduced willingness to participate; participants unaware of the FDA decision demonstrated no change. CONCLUSION: Willingness to participate in preclinical AD trials may have been negatively affected by the FDA's decision to approve aducanumab among those aware of the decision.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Actitud
8.
Front Med (Lausanne) ; 7: 493, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33043024

RESUMEN

Reluctance to undergo lumbar puncture (LP) is a barrier to neurological disease biomarker research. We assessed whether an educational intervention increased willingness to consider research LP and whether message framing modified intervention effectiveness. We randomly assigned 851 recruitment registry enrollees who had previously indicated they were unwilling to be contacted about studies requiring LP to gain or loss framed video educational interventions describing the procedure and the probability of experiencing adverse events. The gain framed intervention emphasized the proportion of individuals free of adverse events; the loss frame emphasized the proportion experiencing adverse events. The primary outcome for the study was the participant's post-intervention agreement to be contacted about studies requiring LP. Participants were mean (SD) age 60.1 years (15.7), 69% female (n = 591), and mostly college educated and white. Among the 699 participants who completed the study, 43% (95% CI: 0.39, 0.47; n = 301) changed their response to agree to be contacted about studies requiring LP. We estimated that participants randomized to the gain framed intervention had 67% higher odds of changing their response compared to those randomized to the loss frame (Odds Ratio = 1.67; 95% CI: 1.24, 2.26; p < 0.001). A classification and regression tree model identified participants' pre-intervention willingness as the strongest predictor of changing response. Education, in particular education that alerts participants to the probability of not experiencing adverse events, may be an effective tool to increase participation rates in research requiring LP.

9.
J Alzheimers Dis ; 63(3): 1055-1063, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29710723

RESUMEN

Potential participant registries are tools to address the challenge of slow recruitment to clinical research. In particular, registries may aid recruitment to secondary prevention clinical trials for Alzheimer's disease (AD), which enroll cognitively normal older individuals meeting specific genetic or biomarker criteria. Evidence of registry effectiveness is sparse, as is guidance on optimal designs or methods of conduct. We report our experiences of developing a novel local potential participant registry that implemented online enrollment and data collection. In the first year of operation, 957 individuals submitted email addresses to the registry, of whom 592 self-reported demographic, family history, and medical data. In addition, registrants provided information related to their interest and willingness to be contacted about studies. Local earned media and community education were the most effective methods of recruitment into the registry. Seventy-six (26%) of 298 registrants contacted about studies in the first year enrolled in those studies. One hundred twenty-nine registrants were invited to enroll in a preclinical AD trial, of whom 25 (18%) screened and 6 were randomized. These results indicate that registries can aid recruitment and provide needed guidance for investigators initiating new local registries.


Asunto(s)
Enfermedad de Alzheimer/terapia , Ensayos Clínicos como Asunto , Selección de Paciente , Sistema de Registros , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Internet , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Am J Clin Nutr ; 108(2): 266-278, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30101333

RESUMEN

Background: The 2010 Dietary Guidelines for Americans (DGA) recommend nutrient needs be met by increasing fruit, vegetable, and whole-grain intake with the use of low-fat or fat-free dairy products and by reducing sodium, solid fats, and added sugars. However, the DGA, as a dietary pattern, have not been tested in an intervention trial. Objective: The aim of this study was to evaluate the impact of a DGA-based diet compared with a representative typical American diet (TAD) on glucose homeostasis and fasting lipids in individuals at risk of cardiometabolic disease. Design: A randomized, double-blind, controlled 8-wk intervention was conducted in overweight and obese women selected according to indexes of insulin resistance or dyslipidemia. Women were randomly assigned to the DGA or TAD group (n = 28 DGA and 24 TAD). The TAD diet was based on average adult intake from the NHANES 2009-2010. The DGA and TAD diets had respective Healthy Eating Index scores of 98 and 62. All foods and beverages were provided during the intervention. Oral-glucose tolerance and fasting lipids were evaluated at 0, 2, and 8 wk of the intervention. Insulin resistance and sensitivity were estimated with the use of surrogates (e.g., homeostasis model assessment of insulin resistance). Results: By design, volunteers maintained their weight during the intervention. Fasting insulin, glucose, triglycerides, oral-glucose tolerance, and indexes of insulin resistance were not affected by either of the diets. Systolic blood pressure decreased in the DGA group (∼-9 mm Hg; P < 0.05). Total and HDL cholesterol also decreased in both groups (P < 0.05). Exploratory analysis comparing volunteers entering the study with insulin resistance and dyslipidemia with those with only dyslipidemia did not show an effect of pre-existing conditions on glucose tolerance or fasting lipid outcomes. Conclusions: The consumption of a DGA dietary pattern for 8 wk without weight loss reduced systolic blood pressure. There were no differences between the DGA and TAD diets in fasting insulin, glucose, indexes of insulin resistance, or fasting lipids. This trial was registered at www.clinicaltrials.gov as NCT02298725.


Asunto(s)
Política Nutricional , Obesidad/dietoterapia , Sobrepeso/dietoterapia , Adulto , Glucemia/análisis , Fibras de la Dieta/administración & dosificación , Método Doble Ciego , Metabolismo Energético , Conducta Alimentaria , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Resistencia a la Insulina , Lípidos/sangre , Persona de Mediana Edad , Obesidad/sangre , Sobrepeso/sangre
11.
Nutrients ; 9(3)2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28257040

RESUMEN

Many Americans are attempting to lose weight with the help of healthcare professionals. Clinicians can improve weight loss results by using technology. Accurate dietary assessment is crucial to effective weight loss. The aim of this study was to validate a computer-led dietary assessment method in overweight/obese women. Known dietary intake was compared to Automated Self-Administered 24-h recall (ASA24) reported intake in women (n = 45), 19-50 years, with body mass index of 27-39.9 kg/m². Participants received nutrition education and reduced body weight by 4%-10%. Participants completed one unannounced dietary recall and their responses were compared to actual intake. Accuracy of the recall and characteristics of respondent error were measured using linear and logistic regression. Energy was underreported by 5% with no difference for most nutrients except carbohydrates, vitamin B12, vitamin C, selenium, calcium and vitamin D (p = 0.002, p < 0.0001, p = 0.022, p = 0.010, p = 0.008 and p = 0.001 respectively). Overall, ASA24 is a valid dietary assessment tool in overweight/obese women participating in a weight loss program. The automated features eliminate the need for clinicians to be trained, to administer, or to analyze dietary intake. Computer-led dietary assessment tools should be considered as part of clinician-supervised weight loss programs.


Asunto(s)
Enfermedades Carenciales/diagnóstico , Dieta Reductora/efectos adversos , Suplementos Dietéticos/efectos adversos , Evaluación Nutricional , Obesidad/dietoterapia , Sobrepeso/dietoterapia , Cooperación del Paciente , Adulto , Índice de Masa Corporal , California , Enfermedades Carenciales/etiología , Diagnóstico por Computador , Diagnóstico Precoz , Ingestión de Energía , Femenino , Humanos , Persona de Mediana Edad , Ciencias de la Nutrición/educación , Educación del Paciente como Asunto , Medicina de Precisión , Pérdida de Peso , Adulto Joven
12.
J Acad Nutr Diet ; 116(11): 1776-1784, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27161025

RESUMEN

BACKGROUND: Previous studies suggest skipping breakfast is associated with lower diet quality, but possible reasons underlying this relationship are not clear. OBJECTIVE: Our aim was to determine the relationship between chronic stress and variations in diet quality in the context of breakfast eating or breakfast skipping. DESIGN: Based on morning eating habits, 40 breakfast eaters and 35 breakfast skippers participated in a cross-sectional study. Diet assessment was based on unannounced 24-hour recalls. PARTICIPANTS/SETTING: Women, ages 18 to 45 years, with a body mass index (calculated as kg/m2) <40 were recruited in the greater Sacramento, CA, area between 2009 and 2013. Only women who consistently ate or skipped breakfast were enrolled. MAIN OUTCOME MEASURES: Compliance with the 2010 Dietary Guidelines for Americans was measured using the Healthy Eating Index 2010 (HEI-2010). Stress and executive function were evaluated with validated questionnaires and a computer-based task, respectively. STATISTICAL ANALYSES PERFORMED: Diet characteristics of breakfast eating and breakfast skipping were evaluated as nutrient densities (amounts per 1,000 kcal) and compared using a one-way analysis of covariance, with body mass index as covariate. Diet and stress variable associations were assessed using Pearson correlations. RESULTS: Despite no observed differences in daily energy intake between breakfast skipping and breakfast eating, overall diet quality (P=0.001), whole grains (P=0.002), fruit (P=0.002), empty calories (P=0.050), fiber (P=0.001), calcium (P=0.001), potassium (P=0.033), and folate (P=0.013) intakes were higher in breakfast eating. In the evening, breakfast skipping consumed more added sugars (P=0.012) and saturated fat (P=0.006). In breakfast skipping, reported stress was associated with empty calories (r=-0.39; P=0.027) and evening intake of added sugars (r=0.501; P=0.005). These relationships were not observed in breakfast eating. CONCLUSIONS: Breakfast skippers were less likely to meet the Dietary Guidelines for Americans and consumed more empty calories at night. Chronic stress was related to evening eating choices and overall empty calories in the diet of breakfast skippers, whereas breakfast eaters' dietary intake did not appear to be affected by chronic stress.


Asunto(s)
Desayuno/psicología , Dieta/efectos adversos , Ingestión de Alimentos/psicología , Conducta Alimentaria/psicología , Estrés Psicológico/etiología , Adolescente , Adulto , California , Estudios Transversales , Dieta/métodos , Registros de Dieta , Femenino , Humanos , Persona de Mediana Edad , Encuestas Nutricionales , Adulto Joven
13.
Physiol Behav ; 140: 215-21, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25545767

RESUMEN

Chronic stress and over-activity in the hypothalamic-pituitary-adrenal (HPA) axis may link breakfast skipping and poor cardiometabolic health. Missing the first major meal of the day in rodents prolongs elevated circulating corticosterone at a time when it's normally decreasing. To extend these findings to humans, we hypothesized that habitual breakfast skippers would display a similar pattern of circulating cortisol and alterations in meal and stress-induced cortisol reactions. Normal weight to obese women aged 18-45 years old who were strictly defined as either breakfast skippers (n=30) or breakfast eaters (n=35) were invited to participate in our study. Normal breakfast habits were maintained for the entire study period and each participant attended 4 lab visits. Over the first 2 lab visits, body composition, fasting clinical chemistries, and self-reports of chronic stress were assessed. On each of 2 additional days (lab visits 3 and 4), salivary free cortisol was measured at home upon waking and at bedtime, and in the lab in response to a standard lunch, ad libitum afternoon snack buffet, and stress and control (relaxation) tasks. The order of the control and stress test visits was randomized. While body weight, body composition, HOMA-IR, total and HDL cholesterol did not statistically differ (p>0.05), both diastolic and systolic blood pressure was elevated (p<0.01) and LDL cholesterol was lower (p=0.04) in the breakfast skipper group. Compared to the breakfast eaters and on the control task visit only, breakfast skippers had higher circulating cortisol from arrival to midafternoon (p<0.01) and during the snack buffet (p<0.05). Furthermore, the lunch-induced cortisol reaction was larger in the 'skippers' (p=0.03). On both stress and control visit days, the diurnal cortisol amplitude was significantly (p=0.02) blunted in breakfast skippers. Self-reports of chronic stress did not differ between the groups. These data indicate that habitually skipping breakfast is associated with stress-independent over-activity in the HPA axis which, if prolonged, may increase risk (e.g., hypertension) for cardiometabolic disease in some people.


Asunto(s)
Presión Sanguínea/fisiología , Desayuno , Privación de Alimentos/fisiología , Hidrocortisona/metabolismo , Hipertensión/etiología , Adolescente , Adulto , Antropometría , Composición Corporal , Peso Corporal , LDL-Colesterol/sangre , Femenino , Humanos , Persona de Mediana Edad , Saliva/metabolismo , Estrés Psicológico/etiología , Encuestas y Cuestionarios , Adulto Joven
14.
Bone ; 64: 138-46, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24709689

RESUMEN

INTRODUCTION: Weight loss reduces co-morbidities of obesity, but decreases bone mass. PURPOSE: Our aims were to (1) determine if adequate dairy intake attenuates weight loss-induced bone loss; (2) evaluate the associations of endocrine, inflammatory and bone markers, anthropometric and other parameters to bone mineral density and content (BMD, BMC) pre- and post-weight loss; and (3) model the contribution of these variables to post weight-loss BMD and BMC. METHODS: Overweight/obese women (BMI: 28-37 kg/m2) were enrolled in an energy reduced (-500 kcal/d; -2092 kJ/d) diet with adequate dairy (AD: 3-4 servings/d; n=25, 32.2±8.8 years) or low dairy (LD: ≤1 serving/d; n=26, 31.7±8.4 years). BMD, BMC and body composition were measured by DXA. Bone markers (CTX, PYD, BAP, OC), endocrine (PTH, vitamin D, leptin, adiponectin, ghrelin, amylin, insulin, GLP-1, PAI-1, HOMA) and inflammatory markers (CRP, IL1-ß, IL-6, IL-8, TNF-α, cortisol) were measured in serum or plasma. PA was assessed by accelerometry. RESULTS: Following weight loss, AD intake resulted in significantly greater (p=0.004) lumbar spine BMD and serum osteocalcin (p=0.004) concentration compared to LD. Pre- and post-body fat was negatively associated with hip and lumbar spine BMC (r=-0.28, p=0.04 to -0.45, p=0.001). Of note were the significant negative associations among bone markers and IL-1ß, TNFα and CRP ranging from r = -0.29 (p=0.04) to r = -0.34 (p=0.01); magnitude of associations did not change with weight loss. Adiponectin was negatively related to change in osteocalcin. Factor analysis resulted in 8 pre- and post-weight loss factors. Pre-weight loss factors accounted for 13.7% of the total variance in pre-weight loss hip BMD; post-weight loss factors explained 19.6% of the total variance in post-weight loss hip BMD. None of the factors contributed to the variance in lumbar spine BMD. CONCLUSION: AD during weight loss resulted in higher lumbar spine BMD and osteocalcin compared to LD. Significant negative associations were observed between bone and inflammatory markers suggesting that inflammation suppresses bone metabolism. Using factor analysis, 19.6% of total variance in post-weight loss hip BMD could be explained by endocrine, immune, and anthropometric variables, but not lumbar spine BMD.


Asunto(s)
Biomarcadores/metabolismo , Composición Corporal , Hormonas/fisiología , Inflamación/fisiopatología , Osteoporosis/fisiopatología , Pérdida de Peso , Absorciometría de Fotón , Adulto , Índice de Masa Corporal , Femenino , Humanos , Osteoporosis/etiología
15.
Physiol Behav ; 106(2): 291-7, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21565212

RESUMEN

The overall objective of this study was to examine the relationship between executive function, specifically decision-making, and weight loss. We used the Iowa Gambling Task (IGT) to characterize decision-making and compared performance on this task to weight loss in obese women (n=29) participating in a 12-week controlled, calorie-reduced intervention. We hypothesized that a greater amount of weight loss over the course of the intervention would be associated with better performance on the IGT, assessed at the end of the intervention. The intervention led to significant weight loss of 5.8±3.1 kg (p<0.05) and fat loss of 5.1±3.0 kg (p<0.05). Body weight and fat mass losses over the 12-week intervention varied widely, ranging from -12.5 kg to 0.0 kg for body weight and -10.4 kg to +0.8 kg for fat mass. A greater amount of body weight loss was correlated (r=0.425; p<0.01) with a higher total score on the IGT. Similarly, the reduction in body fat mass was also correlated with the IGT score (r=0.408; p<0.05). We examined other physiological (salivary cortisol), metabolic (resting energy expenditure), and behavioral (food intake; dietary restraint) factors that might be related to differences in the magnitude of weight loss. Of these variables, ad libitum consumption of energy, fat and protein during a buffet meal was inversely related to weight loss (r=-0.428; p<0.05; r=-0.375; p<0.05 and r=-0.472; p=0.01, respectively). The present study is the first to report an association between diet-induced weight loss and performance on the IGT, and this association was specific to the loss of body fat. Our results suggest that differences in weight loss may be linked to executive function that involves decision-making about events that have emotionally or socially salient ramifications. These findings underscore the need to further investigate higher cognitive and neuroendocrine pathways that may influence or be altered by the process of dieting and weight loss.


Asunto(s)
Toma de Decisiones/fisiología , Dieta Reductora/psicología , Sobrepeso/psicología , Desempeño Psicomotor/fisiología , Pérdida de Peso/fisiología , Tejido Adiposo/metabolismo , Adulto , Ingestión de Alimentos/fisiología , Metabolismo Energético/fisiología , Femenino , Humanos , Hidrocortisona/análisis , Persona de Mediana Edad , Sobrepeso/dietoterapia , Sobrepeso/metabolismo , Sobrepeso/fisiopatología , Cooperación del Paciente/estadística & datos numéricos , Asunción de Riesgos , Saliva/química
16.
J Obes ; 2011: 989657, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21941636

RESUMEN

Background. Research on dairy foods to enhance weight and fat loss when incorporated into a modest weight loss diet has had mixed results. Objective. A 15-week controlled feeding study to determine if dairy foods enhance central fat and weight loss when incorporated in a modest energy restricted diet of overweight and obese adults. Design. A 3-week run-in to establish energy needs; a 12-week 500 kcal/d energy reduction with 71 low-dairy-consuming overweight and obese adults randomly assigned to diets: ≤1 serving dairy/d (low dairy, LD) or ≤4 servings dairy/d (adequate dairy, AD). All foods were weighed and provided by the metabolic kitchen. Weight, fat, intra-abdominal adipose tissue (IAAT), subcutaneous adipose tissue (SAT) macrophage number, SAT inflammatory gene expression, and circulating cytokines were measured. Results. No diet differences were observed in weight, fat, or IAAT loss; nor SAT mRNA expression of inflammation, circulating cytokines, fasting lipids, glucose, or insulin. There was a significant increase (P = 0.02) in serum 25-hydroxyvitamin D in the AD group. Conclusion. Whether increased dairy intake during weight loss results in greater weight and fat loss for individuals with metabolic syndrome deserves investigation. Assessment of appetite, hunger, and satiety with followup on weight regain should be considered.

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