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1.
Pediatr Exerc Sci ; : 1-8, 2020 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-32335525

RESUMEN

OBJECTIVE: To conduct a preliminary assessment of the relationships between cardiorespiratory fitness, adiposity, and cardiometabolic health using gold standard measures in diverse youth ranging from overweight to severe obesity. METHODS: Twenty of 30 participants (mean [SD]; age 13.2 [1.8] y, 55% female, 45% African American) met the criteria for VO2peak during a graded cycle ergometer test to volitional fatigue. The body composition was measured by dual-energy X-ray absorptiometry (percentage of body fat, fat mass index, and fat-free mass) and magnetic resonance imaging (abdominal visceral and subcutaneous [SAT] adipose tissue). The VO2peak was expressed relative to fat-free mass. Fasting lipid levels, glycemic biomarkers, and vital signs were examined individually and used in a composite cardiometabolic risk score. Accelerometer-measured physical activity and sedentary time were included as covariates. RESULTS: VO2peak was negatively associated with abdominal SAT (r = -.49, P < .05), but not visceral adipose tissue or markers of cardiometabolic health. The association between SAT and VO2peak was partly explained by habitual sedentary time. CONCLUSIONS: We demonstrated a significant negative association between cardiorespiratory fitness and SAT in a diverse group of high-risk youth. The inclusion of rigorous, laboratory-based measures and youth with severe obesity extends the previous work in pediatric populations.

2.
Br J Nutr ; : 1-27, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32301407

RESUMEN

Cranberries are high in polyphenols and epidemiologic studies have shown a high polyphenol diet may reduce risk factors for diabetes and cardiovascular disease. This study aimed to determine if short term cranberry beverage consumption would improve insulin sensitivity and other cardiovascular risk factors. Thirty-five obese individuals with elevated fasting glucose or impaired glucose tolerance participated in a randomized, double blind, placebo controlled, parallel designed pilot trial. Participants consumed 450 mL of low-calorie cranberry beverage or placebo daily for 8 weeks. Changes in insulin sensitivity and cardiovascular risk factors including vascular reactivity, blood pressure, resting metabolic rate, glucose tolerance, lipid profiles, and oxidative stress biomarkers were evaluated. Change in insulin sensitivity via hyperinsulinemic euglycemic clamp was not different between the two groups. Levels of 8-isoprostane (biomarker of lipid peroxidation) decreased in the cranberry group but increased in the placebo group (-2.18 pg/mL vs +20.81 pg/mL, p=0.02). When stratified by baseline C-reactive protein (CRP) levels, participants with high CRP levels (> 4 mg/L) benefited more from cranberry consumption. In this group, significant differences in the mean change from baseline between the cranberry (n=10) and the placebo groups (n=7) in levels of triglyceride (-13.75% vs +10.32%; p=0.04), nitrate (+3.26 µM/L vs -6.28 µM/L; p=0.02), and 8-isoprostane (+0.32 pg/mL vs +30.8 pg/mL; p=0.05) were observed. These findings indicate that 8 weeks of daily cranberry beverage consumption may not impact insulin sensitivity but may be helpful in lowering triglycerides and changing certain oxidative stress biomarkers in obese individuals with a proinflammatory state.

3.
Obesity (Silver Spring) ; 28(5): 882-892, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32144895

RESUMEN

OBJECTIVE: This study aimed to determine whether different measures of habitual physical activity (PA) at baseline predict weight change, weight compensation, and changes in energy intake (EI) during a 24-week supervised aerobic exercise intervention. METHODS: Data from 108 participants (78 women; 48.7 [SD: 11.6] years; BMI 31.4 [SD: 4.6] kg/m2 ), randomly assigned to either the moderate-dose exercise group (8 kcal/kg of body weight per week) or the high-dose exercise group (20 kcal/kg of body weight per week) of the Examination of Mechanisms of Exercise-induced Weight Compensation (E-MECHANIC) trial, were analyzed. Moderate-to-vigorous PA (MVPA), steps per day, and PA energy expenditure (PAEE) were measured with SenseWear armbands (BodyMedia, Pittsburgh, Pennsylvania), and total activity energy expenditure and EI were estimated with doubly labeled water, all over 2 weeks, before and toward the end of the intervention. Multiple linear regression models, adjusted for sex, exercise group, and baseline value of the outcome, were used. RESULTS: Baseline habitual MVPA levels predicted weight change (ß = -0.275; P = 0.020), weight compensation (ß = -0.238; P = 0.043), and change in EI (ß = -0.318; P = 0.001). Associations between baseline PAEE and outcomes were comparable, whereas steps per day and, importantly, total activity energy expenditure (via doubly labeled water) did not significantly predict change in weight-related outcomes. CONCLUSIONS: While acknowledging substantial variability in the data, on average, lower baseline habitual MVPA and PAEE levels were associated with less weight loss from exercise, higher compensation, and increased EI.

4.
Obesity (Silver Spring) ; 28(2): 268-276, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31891231

RESUMEN

OBJECTIVE: The aim of this study is to characterize changes in body composition during pregnancy in women with obesity. METHODS: Fifty-four healthy women with obesity (class 1, 30-34.9 kg/m2 : n = 25; class 2, 35-39.9 kg/m2 : n = 21; class 3, ≥ 40.0 kg/m2 : n = 8) expecting a singleton pregnancy were studied. Body composition was measured in early pregnancy (13-16 weeks), midpregnancy (24-27 weeks), and late pregnancy (35-37 weeks) using air displacement plethysmography, stable isotopes, and skinfold thickness measurements. Fasting glucose, insulin, and leptin were measured. RESULTS: The gain in fat-free mass was lower in the second trimester compared with the third (2.7 ± 0.2 to 5.3 ± 0.2 kg; P < 0.001), whereas fat mass accumulation declined over time (0.6 ± 0.3 to -0.7 ± 0.4 kg; P = 0.005). Women with class 1 and 2 obesity gained 1.1 ± 0.7 kg of fat mass during pregnancy, while women with class 3 obesity lost 4.1 ± 0.6 kg (both P < 0.001). The difference in fat accumulation between obesity classes was observed only in the second trimester (P = 0.02). Gestational weight gain was associated positively with changes in plasma concentrations of insulin, leptin, and insulin resistance (all P < 0.01). CONCLUSIONS: Gestational weight gain in pregnancy differs by obesity class and trimester. Women with class 3 obesity gain less body weight and fat mass. Fat mass gain is most likely preventable in the second trimester.

5.
Med Sci Sports Exerc ; 52(2): 408-416, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31939911

RESUMEN

PURPOSE: To examine the impact of a community-based exercise training intervention on cardiometabolic outcomes in African American men who have a family history of type 2 diabetes. METHODS: The Aerobic Plus Resistance Training and Insulin Sensitivity in African American Men (ARTIIS) study randomized participants into either an exercise training intervention or an information only control group for 5 months. The exercise training intervention consisted of 150 min of moderate intensity aerobic activity and 2 d of resistance training per week, consistent with the current federal physical activity guidelines. Participants in the control group received monthly newsletters featuring topics focused heavily on type 2 diabetes education and prevention. Outcome data were analyzed using repeated-measures ANCOVA models and incorporating both intention-to-treat and per-protocol principles. RESULTS: Adherence to the aerobic and resistance training prescriptions were between 77% and 79%. Despite significant within group improvements in glucose and insulin levels (fasting, 2 h, 2 h minus baseline) and Homeostatic Model 2-Insulin Resistance, there were not significant between group differences. There was a marginally significant between group difference for Homeostatic Model 2-Beta (P < 0.06), and significant between group differences in peak cardiorespiratory fitness (P < 0.001) and waist circumference (P = 0.03). CONCLUSIONS: These findings suggest that exercise training in accordance with the current national recommendations is effective in improving some health parameters in middle-age African American men who have a family history of type 2 diabetes, but did not have a significant impact on glycemic status.

6.
J Clin Endocrinol Metab ; 105(3)2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31965161

RESUMEN

OBJECTIVE: Fasting plasma glucose (FPG), 2-hour plasma glucose (2hPG) from a 75-g oral glucose tolerance test (OGTT) and glycated hemoglobin (HbA1c) can lead to different results when diagnosing prediabetes and diabetes. The Hemoglobin Glycation Index (HGI) quantifies the interindividual variation in glycation resulting in discrepancies between FPG and HbA1c. We used data from the Vitamin D and Type 2 Diabetes (D2d) study to calculate HGI, to identify HGI-associated variables, and to determine how HGI affects prediabetes and diabetes diagnosis. MEASUREMENTS: A linear regression equation [HbA1c (%) = 0.0164 × FPG (mg/dL) + 4.2] was derived using the screening cohort (n = 6829) and applied to calculate predicted HbA1c. This was subtracted from the observed HbA1c to determine HGI in the baseline cohort with 2hPG data (n = 3945). Baseline variables plus prediabetes and diabetes diagnosis by FPG, HbA1c, and 2hPG were compared among low, moderate, and high HGI subgroups. RESULTS: The proportion of women and Black/African American individuals increased from low to high HGI subgroups. Mean FPG decreased and mean HbA1c increased from low to high HGI subgroups, consistent with the HGI calculation; however, mean 2hPG was not significantly different among HGI subgroups. CONCLUSIONS: High HGI was associated with Black race and female sex as reported previously. The observation that 2hPG was not different across HGI subgroups suggests that variation in postprandial glucose is not a significant source of population variation in HGI. Exclusive use of HbA1c for diagnosis will classify more Black individuals and women as having prediabetes compared with using FPG or 2hPG.

7.
J Adolesc Health ; 2020 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-31987725

RESUMEN

PURPOSE: The aim of the study was to assess the associations of meeting physical activity (PA), sleep, and dietary guidelines with cardiometabolic risk factors and adiposity in adolescents. METHODS: The sample included adolescents aged 10-16 years. Accelerometry was used to measure PA and sleep over 7 days, 24 h/d. The PA guideline was defined as ≥60 min/d of moderate-to-vigorous PA. The sleep guideline was 9-11 hours (10-13 years) or 8-10 hours (14-16 years) per night. The dietary guideline was based on the Healthy Eating Index calculated from dietary recalls. Cardiometabolic risk factors and adiposity were assessed in an in-patient setting. Linear regression was used to examine the association between meeting each guideline and cardiometabolic risk factors/adiposity, adjusted for confounders and meeting other guidelines. RESULTS: Of the 342 participants, 251 (73%) provided complete measurements. Adolescents were 12.5 ± 1.9 years (African American [37%] and white [57%], girls [54%], and overweight or obesity [48%]). Half met the sleep guideline (52%), few met the PA guideline (11%), and the top quintile was preselected as meeting the diet guideline (20%). Most met one (47%) or no guidelines (35%), and few met multiple guidelines (18%). Meeting the PA guideline was associated with lower cardiometabolic risk factors and adiposity (p < .05 for all). Compared with meeting no guidelines, those who met multiple guidelines had lower cardiometabolic risk factors and adiposity (p < .05 for all). CONCLUSIONS: Few met the PA or multiple guidelines, and those not meeting guidelines were associated with adverse cardiometabolic factors and adiposity. Multidisciplinary strategies for improving multiple behaviors are needed to improve adolescent health.

8.
Diabetes Obes Metab ; 2019 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-31696603

RESUMEN

AIMS: To assess the pharmacokinetic (PK) and pharmacodynamic characteristics of VI-0521, a fixed-dose combination of immediate-release phentermine (PHEN) and extended-release topiramate (TPM) in adolescents aged 12 to 17 years with obesity, and to report weight loss and adverse events using this drug combination. MATERIALS AND METHODS: This was a multicentre, randomized, double-blind, parallel-design, placebo-controlled study in adolescents with obesity. A total of 42 adolescents were randomly assigned in a 1:1:1 ratio to placebo, or to a mid-dose (PHEN/TPM 7.5 mg/46 mg), or a top-dose (PHEN/TPM 15 mg/92 mg) of VI-0521. A total of 26 adolescents were included in the PK analysis (14 from the mid-dose group and 12 from the top-dose group). RESULTS: On day 56, arithmetic means of terminal elimination half-life, apparent clearance (CL/F) and apparent central volume of distribution (Vc/F) were consistent across dose levels for both PHEN and TPM. Arithmetic means of CL/F and Vc/F for PHEN and TPM administered as a combination in adolescents with obesity were within 10% to 30% of those previously assessed in adults with obesity enrolled in phase II and III studies. A higher proportion of adolescents in both the mid- and top-dose groups (13.3% and 50.0%, respectively) compared with placebo (0.0%) reached ≥5% weight loss at day 56. The least squares (LS) mean change in systolic blood pressure from baseline to day 56 was -5.2 mmHg for the placebo group, -2.5 mmHg for the mid-dose group, and - 5.5 mmHg for the top-dose group. The LS mean change in diastolic blood pressure from baseline to day 56 was -2.4 mmHg for the placebo group, +3.8 mmHg for the mid-dose group, and + 2.0 mmHg for the top-dose group. Participants in the top-dose group had increases in heart rate from baseline of 4.1 bpm, while participants in the mid-dose group experienced a mean decrease in heart rate of 4.5 bpm at day 56. Both PHEN/TPM dose combinations were safe and well tolerated. CONCLUSIONS: Treatment of adolescents with obesity using a fixed-dose combination of PHEN/TPM for 8 weeks resulted in exposure to PHEN and TPM that was comparable to that observed in adults, statistically significant weight loss, and a tolerable safety profile. These data indicate that both mid- and top-dose levels are appropriate for longer-term safety and efficacy studies in adolescents.

9.
Med Sci Sports Exerc ; 2019 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-31479007

RESUMEN

PURPOSE: To examine the impact of a community-based exercise training intervention on cardiometabolic outcomes in African American men who have a family history of type 2 diabetes. METHODS: The Aerobic Plus Resistance Training and Insulin Sensitivity in African American Men (ARTIIS) study randomized participants into either an exercise training intervention or an information only control group for 5 months. The exercise training intervention consisted of 150 minutes of moderate intensity aerobic activity and two days of resistance training per week, consistent with the current federal physical activity guidelines. Participants in the control group received monthly newsletters featuring topics focused heavily on type 2 diabetes education and prevention. Outcome data were analyzed using repeated measures analysis of covariance (ANCOVA) models and incorporating both intention-to-treat and per-protocol principles. RESULTS: Adherence to the aerobic and resistance training prescriptions were between 77% and 79%. Despite significant within group improvements in glucose and insulin levels (fasting, 2-hour, 2-hour minus baseline) and Homeostatic Model 2-Insulin Resistance, there were not significant between group differences. There was a marginally significant between group difference for Homeostatic Model 2-Beta (p < 0.06), and significant between group differences in peak cardiorespiratory fitness (p < 0.001) and waist circumference (p = 0.03). CONCLUSION: These findings suggest that exercise training in accordance with the current national recommendations is effective in improving some health parameters in middle-aged African American men who have a family history of type 2 diabetes, but did not have a significant impact on glycemic status. TRIAL REGISTRATION: The study is registered in clinicaltrials.gov [NCT01787617].

11.
Eur J Appl Physiol ; 119(9): 2095-2103, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31367909

RESUMEN

PURPOSE: Heart rate recovery (HRR) after exercise is an independent risk factor for cardiovascular disease and mortality. Regular aerobic exercise can improve HRR, yet little is known regarding the dose necessary to promote increases. The aim was to assess the impact of different doses of vigorous-intensity aerobic exercise on HRR in individuals with overweight/obesity. METHODS: Data from 137 sedentary adults with overweight/obesity from E-MECHANIC were analyzed. Participants were randomized to either a moderate-dose exercise group (8 kcal/kg body weight/week; KKW), a high-dose exercise group (20 KKW), or a non-exercise control group. HRR was defined as the difference between peak heart rate (HR) during a graded exercise test and the HR after exactly 1 min of active recovery at 1.5 mph and level grade. RESULTS: Change in HRR did not differ significantly by exercise group; therefore, the data from both exercise groups were combined. The combined exercise group showed an improvement in HRR of 2.7 bpm (95% CI 0.1, 5.4; p = 0.04) compared to the control group. Those participants who lost more weight during the intervention (non-compensators) increased HRR by 6.2 bpm (95% CI 2.8, 9.5; p < 0.01) compared to those who lost less weight (compensators). Multiple linear regression models indicated that improvements in HRR are independently associated with increases in VO2peak (ß = 0.4; 95% CI 0.1, 0.7; p = 0.04) but also influenced by concomitant weight loss (ß = 0.6; 95% CI 0.2, 1.1; p = 0.01). CONCLUSION: Exercise-induced improvements in 1-min HRR are likely due to increases in cardiorespiratory fitness as well as concomitant weight loss.


Asunto(s)
Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiología , Obesidad/fisiopatología , Sobrepeso/fisiopatología , Adulto , Peso Corporal/fisiología , Capacidad Cardiovascular/fisiología , Prueba de Esfuerzo/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Conducta Sedentaria , Pérdida de Peso/fisiología
12.
J Clin Invest ; 130: 4682-4690, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31369400

RESUMEN

BACKGROUND: In women with obesity, excess gestational weight gain (≥270 g/week) occurs in two out of three pregnancies and contributes to metabolic impairments in both mother and baby. To improve obstetrical care, objectively assessed information on energy balance is urgently needed. The objective of this study was to characterize determinants of gestational weight gain in women with obesity. METHODS: This was a prospective, observational study of pregnant women with obesity. The primary outcome was energy intake calculated by the energy intake-balance method. Energy expenditure was measured by doubly-labeled water and whole-room indirect calorimetry and body composition as 3-compartment model by air displacement plethysmography and isotope dilution in early (13-16 weeks) and late pregnancy (35-37 weeks). RESULTS: In pregnant women with obesity (n=54), recommended weight gain (n=8, 15%) during the second and third trimesters was achieved when energy intake was 125±52 kcal/d less than energy expenditure. In contrast, women with excess weight gain (67%) consumed 186±29 kcal/d more than they expended (P<0.001). Energy balance affected maternal adiposity (recommended: -2.5±0.8 kg fat mass, excess: +2.2±0.5, inadequate: -4.5±0.5, P<0.001), but not fetal growth. Weight gain was not related to demographics, activity, metabolic biomarkers, or diet quality. We estimated that energy intake requirements for recommended weight gain during the second and third trimesters were not increased as compared to energy requirements early in pregnancy (34±53 kcal/d, P=0.83). CONCLUSIONS: We here provide the first evidence-based recommendations for energy intake in pregnant women with obesity. Contrary to current recommendations, energy intake should not exceed energy expenditure. FUNDING: This study was funded by the National Institutes of Health (R01DK099175; Redman, U54GM104940 and P30DK072476; Core support). TRIAL REGISTRATION: clinicaltrials.gov: NCT01954342.

13.
Nutrients ; 11(9)2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31466276

RESUMEN

African Americans (AAs) have a higher obesity risk than Whites; however, it is unclear if appetite-related hormones and food intake are implicated. We examined differences in appetite-related hormones, appetite, and food intake between AAs (n = 53) and Whites (n = 111) with overweight or obesity. Participants were randomized into a control group or into supervised, controlled exercise groups at 8 kcal/kg of body weight/week (KKW) or 20 KKW. Participants consumed lunch and dinner at baseline and follow-up, with appetite and hormones measured before and after meals (except leptin). At baseline, AAs had lower peptide YY (PYY; p < 0.01) and a blunted elevation in PYY after lunch (p = 0.01), as well as lower ghrelin (p = 0.02) and higher leptin (p < 0.01) compared to Whites. Despite desire to eat being lower and satisfaction being higher in AAs relative to Whites (p ≤ 0.03), no racial differences in food intake were observed. Compared to Whites, leptin increased in the 8 KKW group in AAs (p = 0.01), yet no other race-by-group interactions were evident. Differences in appetite-related hormones between AAs and Whites exist; however, their influence on racial disparities in appetite, food intake, and obesity within this trial was limited.


Asunto(s)
Afroamericanos , Regulación del Apetito/etnología , Ingestión de Energía/etnología , Grupo de Ascendencia Continental Europea , Disparidades en el Estado de Salud , Obesidad/etnología , Hormonas Peptídicas/sangre , Adulto , Biomarcadores/sangre , Femenino , Ghrelina/sangre , Humanos , Leptina/sangre , Louisiana/epidemiología , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/fisiopatología , Péptido YY/sangre , Periodo Posprandial , Factores de Tiempo
14.
Obesity (Silver Spring) ; 27(8): 1244-1254, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31339000

RESUMEN

OBJECTIVE: Eating earlier in the daytime to align with circadian rhythms in metabolism enhances weight loss. However, it is unknown whether these benefits are mediated through increased energy expenditure or decreased food intake. Therefore, this study performed the first randomized trial to determine how meal timing affects 24-hour energy metabolism when food intake and meal frequency are matched. METHODS: Eleven adults with overweight practiced both early time-restricted feeding (eTRF) (eating from 8 am to 2 pm) and a control schedule (eating from 8 am to 8 pm) for 4 days each. On the fourth day, 24-hour energy expenditure and substrate oxidation were measured by whole-room indirect calorimetry, in conjunction with appetite and metabolic hormones. RESULTS: eTRF did not affect 24-hour energy expenditure (Δ = 10 ± 16 kcal/d; P = 0.55). Despite the longer daily fast (intermittent fasting), eTRF decreased mean ghrelin levels by 32 ± 10 pg/mL (P = 0.006), made hunger more even-keeled (P = 0.006), and tended to increase fullness (P = 0.06-0.10) and decrease the desire to eat (P = 0.08). eTRF also increased metabolic flexibility (P = 0.0006) and decreased the 24-hour nonprotein respiratory quotient (Δ = -0.021 ± 0.010; P = 0.05). CONCLUSIONS: Meal-timing interventions facilitate weight loss primarily by decreasing appetite rather than by increasing energy expenditure. eTRF may also increase fat loss by increasing fat oxidation.

15.
Am J Clin Nutr ; 110(3): 583-592, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31172175

RESUMEN

BACKGROUND: Exercise is recommended for weight management, yet exercise produces less weight loss than expected, which is called weight compensation. The mechanisms for weight compensation are unclear. OBJECTIVE: The aim of this study was to identify the mechanisms responsible for compensation. METHODS: In a randomized controlled trial conducted at an academic research center, adults (n = 198) with overweight or obesity were randomized for 24 wk to a no-exercise control group or 1 of 2 supervised exercise groups: 8 kcal/kg of body weight/wk (KKW) or 20 KKW. Outcome assessment occurred at weeks 0 and 24. Energy intake, activity, and resting metabolic rate (RMR) were measured with doubly labeled water (DLW; with and without adjustments for change in RMR), armband accelerometers, and indirect calorimetry, respectively. Appetite and compensatory health beliefs were measured by self-report. RESULTS: A per-protocol analysis included 171 participants (72.5% women; mean ± SD baseline body mass index: 31.5 ± 4.7 kg/m2). Significant (P < 0.01) compensation occurred in the 8 KKW (mean: 1.5 kg; 95% CI: 0.9, 2.2 kg) and 20 KKW (mean: 2.7 kg; 95% CI: 2.0, 3.5 kg) groups, and compensation differed significantly between the exercise groups (P = 0.01). Energy intake by adjusted DLW increased significantly (P < 0.05) in the 8 KKW (mean: 90.7 kcal/d; 95% CI: 35.1, 146.4 kcal/d) and 20 KKW (mean: 123.6 kcal/d; 95% CI: 64.5, 182.7 kcal/d) groups compared with control (mean: -2.3 kcal/d; 95% CI: -58.0, 53.5 kcal/d). Results were similar without DLW adjustment. RMR and physical activity (excluding structured exercise) did not differentially change among the 3 groups. Participants with higher compared with lower compensation reported increased appetite ratings and beliefs that healthy behaviors can compensate for unhealthy behaviors. Furthermore, they increased craving for sweet foods, increased sleep disturbance, and had worsening bodily pain. CONCLUSIONS: Compensation resulted from increased energy intake and concomitant increases in appetite, which can be treated with dietary or pharmacological interventions. Compensation was not due to activity or metabolic changes. This trial was registered at clinicaltrials.gov as NCT01264406.

16.
N Engl J Med ; 381(6): 520-530, 2019 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-31173679

RESUMEN

BACKGROUND: Observational studies support an association between a low blood 25-hydroxyvitamin D level and the risk of type 2 diabetes. However, whether vitamin D supplementation lowers the risk of diabetes is unknown. METHODS: We randomly assigned adults who met at least two of three glycemic criteria for prediabetes (fasting plasma glucose level, 100 to 125 mg per deciliter; plasma glucose level 2 hours after a 75-g oral glucose load, 140 to 199 mg per deciliter; and glycated hemoglobin level, 5.7 to 6.4%) and no diagnostic criteria for diabetes to receive 4000 IU per day of vitamin D3 or placebo, regardless of the baseline serum 25-hydroxyvitamin D level. The primary outcome in this time-to-event analysis was new-onset diabetes, and the trial design was event-driven, with a target number of diabetes events of 508. RESULTS: A total of 2423 participants underwent randomization (1211 to the vitamin D group and 1212 to the placebo group). By month 24, the mean serum 25-hydroxyvitamin D level in the vitamin D group was 54.3 ng per milliliter (from 27.7 ng per milliliter at baseline), as compared with 28.8 ng per milliliter in the placebo group (from 28.2 ng per milliliter at baseline). After a median follow-up of 2.5 years, the primary outcome of diabetes occurred in 293 participants in the vitamin D group and 323 in the placebo group (9.39 and 10.66 events per 100 person-years, respectively). The hazard ratio for vitamin D as compared with placebo was 0.88 (95% confidence interval, 0.75 to 1.04; P = 0.12). The incidence of adverse events did not differ significantly between the two groups. CONCLUSIONS: Among persons at high risk for type 2 diabetes not selected for vitamin D insufficiency, vitamin D3 supplementation at a dose of 4000 IU per day did not result in a significantly lower risk of diabetes than placebo. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; D2d ClinicalTrials.gov number, NCT01942694.).


Asunto(s)
Colecalciferol/uso terapéutico , Diabetes Mellitus Tipo 2/prevención & control , Suplementos Dietéticos , Estado Prediabético/tratamiento farmacológico , Vitaminas/uso terapéutico , Administración Oral , Anciano , Colecalciferol/administración & dosificación , Supervivencia sin Enfermedad , Método Doble Ciego , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estado Prediabético/sangre , Factores de Riesgo , Insuficiencia del Tratamiento , Vitamina D/análogos & derivados , Vitamina D/sangre , Vitaminas/administración & dosificación
17.
J Clin Endocrinol Metab ; 104(10): 4492-4500, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31058974

RESUMEN

CONTEXT: It is unclear how adolescent glycemic status relates to brain health in adulthood. OBJECTIVE: To assess the association between adolescent fasting plasma glucose (FPG) and MRI-based brain measures in midlife. DESIGN: Between 1973 and 1992, the Bogalusa Heart Study (BHS) collected FPG from children, 3 to 18 years old, and followed up between 1992 and 2018. Cognitive tests and brain MRI were collected in 2013 to 2016 and 2018. SETTING: Observational longitudinal cohort study. PARTICIPANTS: Of 1298 contacted BHS participants, 74 completed screening, and 50 completed MRI. MAIN OUTCOME MEASURES: Mean FPG per participant at ages <20, 20 to 40, and over 40 years old; brain white matter hyperintensity (WMH) volume, gray matter volume, and functional MRI (fMRI) activation to a Stroop task; tests of logical and working memory, executive function, and semantic fluency. RESULTS: At MRI, participants were middle aged (51.3 ± 4.4 years) and predominantly female (74%) and white (74%). Mean FPG was impaired for zero, two, and nine participants in pre-20, 20 to 40, and over-40 periods. The pre-20 mean FPG above the pre-20 median value (i.e., above 83.5 mg/dL) was associated with greater WMH volume [mean difference: 0.029% of total cranial volume, CI: (0.0059, 0.052), P = 0.015] and less fMRI activation [-1.41 units (-2.78, -0.05), P = 0.043] on midlife MRI compared with below-median mean FPG. In controlling for over-40 mean FPG status did not substantially modify the associations. Cognitive scores did not differ by pre-20 mean FPG. CONCLUSIONS: High-normal adolescent FPG may be associated with preclinical brain changes in midlife.

18.
J Phys Act Health ; 16(2): 141-148, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30636499

RESUMEN

BACKGROUND: Active workstations offer the potential for augmenting energy expenditure (EE) in sedentary occupations. However, comparisons of EE during pedal and treadmill desk usage at self-selected intensities are lacking. METHODS: A sample of 16 adult participants (8 men and 8 women; 33.9 [7.1] y, 22.5 [2.7] kg/m2) employed in sedentary occupations had their EE measured using indirect calorimetry during 4 conditions: (1) seated rest, (2) seated typing in a traditional office chair, (3) self-paced pedaling on a pedal desk while typing, and (4) self-paced walking on a treadmill desk while typing. RESULTS: For men and women, self-paced pedal and treadmill desk typing significantly increased EE above seated typing (pedal desk: +1.20 to 1.28 kcal/min and treadmill desk: +1.43 to 1.93 kcal/min, P < .001). In men, treadmill desk typing (3.46 [0.19] kcal/min) elicited a significantly higher mean EE than pedal desk typing (2.73 [0.21] kcal/min, P < .001). No significant difference in EE was observed between treadmill desk typing (2.68 [0.19] kcal/min) and pedal desk typing among women (2.52 [0.21] kcal/min). CONCLUSIONS: Self-paced treadmill desk usage elicited significantly higher EE than self-paced pedal desk usage in men but not in women. Both pedal and treadmill desk usage at self-selected intensities elicited approximate 2-fold increases in EE above what would typically be expected during traditional seated office work.

20.
Pediatrics ; 142(6)2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30381474

RESUMEN

: media-1vid110.1542/5839981580001PEDS-VA_2018-0290Video Abstract OBJECTIVES: To determine the association of antibiotic use with weight outcomes in a large cohort of children. METHODS: Health care data were available from 2009 to 2016 for 35 institutions participating in the National Patient-Centered Clinical Research Network. Participant inclusion required same-day height and weight measurements at 0 to <12, 12 to <30, and 48 to <72 months of age. We assessed the association between any antibiotic use at <24 months of age with BMI z score and overweight or obesity prevalence at 48 to <72 months (5 years) of age, with secondary assessments of antibiotic spectrum and age-period exposures. We included children with and without complex chronic conditions. RESULTS: Among 1 792 849 children with a same-day height and weight measurement at <12 months of age, 362 550 were eligible for the cohort. One-half of children (52%) were boys, 27% were African American, 18% were Hispanic, and 58% received ≥1 antibiotic prescription at <24 months of age. At 5 years, the mean BMI z score was 0.40 (SD 1.19), and 28% of children had overweight or obesity. In adjusted models for children without a complex chronic condition at 5 years, we estimated a higher mean BMI z score by 0.04 (95% confidence interval [CI] 0.03 to 0.05) and higher odds of overweight or obesity (odds ratio 1.05; 95% CI 1.03 to 1.07) associated with obtaining any (versus no) antibiotics at <24 months. CONCLUSIONS: Antibiotic use at <24 months of age was associated with a slightly higher body weight at 5 years of age.


Asunto(s)
Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Obesidad Pediátrica/inducido químicamente , Obesidad Pediátrica/epidemiología , Índice de Masa Corporal , Preescolar , Estudios de Cohortes , Esquema de Medicación , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Obesidad Pediátrica/diagnóstico
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