Development and cross-validation of prediction equations for estimating resting energy expenditure in severely obese Caucasian children and adolescents

The objectives of the present study were to develop and cross-validate new equations for predicting resting energy expenditure (REE) in severely obese children and adolescents, and to determine the accuracy of new equations using the Bland–Altman method. The subjects of the study were 574 obese Caucasian children and adolescents (mean BMI z-score 3·3). REE was determined by indirect calorimetry and body composition by bioelectrical impedance analysis. Equations were derived by stepwise multiple regression analysis using a calibration cohort of 287 subjects and the equations were cross-validated in the remaining 287 subjects. Two new specific equations based on anthropometric parameters were generated as follows: (1) REE=(Sex×892·68)−(Age×115·93)+(Weight×54·96)+(Stature×1816·23)+1484·50 (R2 0·66; se 1028·97 kJ); (2) REE=(Sex×909·12)−(Age×107·48)+(fat-free mass×68·39)+(fat mass×55·19)+3631·23 (R2 0·66; se 1034·28 kJ). In the cross-validation group, mean predicted REE values were not significantly different from the mean measured REE for all children and adolescents, as well as for boys and for girls (difference <2 %) and the limits of agreement (±2 sd) were +2·06 and −1·77 MJ/d (NS). The new prediction equations allow an accurate estimation of REE in groups of severely obese children and adolescents. These equations might be useful for health care professionals and researchers when estimating REE in severely obese children and adolescents

Psychometric properties of the Fatigue Severity Scale in obese patients

BACKGROUND: The aim of this study was to examine the psychometric properties of the Fatigue Severity Scale (FSS) to verify whether this instrument is a valid tool to measure fatigue in obese patients, and to examine the prevalence of fatigue in obese patients. METHODS: Before and after a three-week residential multidisciplinary integrated weight reduction program, 220 patients were asked to fill in the questionnaires: FSS, Profile of Mood States (Fatigue-Inertia subscale, POMS-Fatigue, and Vigor-Activity subscale, POMS-Vigor), and the Obesity-Related Well-Being (ORWELL-97). A subsample of 50 patients completed the questionnaire within two days. RESULTS: The prevalence of fatigue using a cut-off value of 4 for the FSS score was 59%. Correlations were found between FSS and POMS-Fatigue and -Vigor scores (r = 0.58 and 0.53, respectively). A relation was also found between FSS and ORWELL97 (r = 0.52, 0.42 to 0.61). From the factorial analysis only 1 factor was extracted explaining 63% of variance, with factor loading values ranging from 0.71 (item 7) to 0.87 (item 6). Intraclass Correlation Coefficient was 0.89 (0.82 to 0.94), while the agreement as measured using the Standard Error of Measurement was 0.43 (0.36 to 0.54) corresponding to 13% (11 to 17%). Cronbach’s alpha values ranged from 0.94 to 0.93. The internal responsiveness of FSS was comparable to the ORWELL97 (Standardized Response Mean = 0.50 and 0.44, respectively). CONCLUSIONS: Fatigue is an important and frequent symptom in obese patients and therefore should be routinely assessed in both research and clinical practice. This can be achieved using the FSS, which is a short, simple, valid and reliable tool for assessing and quantifying fatigue in obese patients

GH Responsiveness to Combined GH-Releasing Hormone and Arginine Administration in Obese Patients with Fibromyalgia Syndrome

Reportedly, fibromyalgia (FM) is frequently associated with reduced IGF-1 levels and GH hyporesponsiveness to different GH stimulation tests. Since there is a high prevalence of obesity in FM, and obesity itself is characterized by hyposomatotropism, the aim of this study was to assess IGF-1 levels and GH responsiveness in sixteen severely obese women suffering from FM, who, subdivided into two subgroups on the basis of their age-dependent IGF-1 values (> or <−2 SDS), underwent the combined GHRH plus arginine test. Four out of 16 obese women with FM (25%) had low IGF-1 SDS values, 2 cases of this subgroup (12.5%) failing also to normally respond to the test. Among patients with normal GH responses, 4 showed a delayed GH peak. The subgroup with low IGF-1 SDS values had higher BMI than that with normal IGF-1 SDS. GH peak and area under the curve were not correlated with CRP, ESR, or tender point score, while significant correlations were found with fat-free mass and fat mass. In conclusion, this study shows the existence of a high prevalence of GH-IGF-1 dysfunction in patients with both FM and obesity, presumably as a consequence of the obese rather than fibromyalgic condition

Effect of Gender and Obesity On Electrical Current Thresholds

Import JabRef | WosArea Neurosciences and NeurologyInternational audienceIntroduction: In this study we investigated the influence of gender and obesity on electrical current thresholds in an attempt to optimize the application of skeletal muscle electrical stimulation (ES) in clinical practice. Methods: Thirty-two obese and 35 age-matched, non-obese men and women received graded ES to the quadriceps muscle for sensory (detection) and motor (contraction) threshold assessment. Con-comitant pain and tolerance to ES were recorded. Results: Sensory threshold was lower in women than in men (P inf 0.001), both obese and non-obese. Sensory and motor thresholds were higher in obese than in non-obese subjects (P inf 0.05), and body mass index was a strong predictor of motor excitability (r(2) = 0.56-0.61). Current tolerance to motor stimulation was reduced in obese individuals, particularly in women, whereas pain was not influenced by gender or obesity. Conclusions: We suggest that both gender and obesity factors should be carefully considered in the design of rational ES treatments. Muscle Nerve 44: 202-207, 201

Acute respiratory muscle unloading by normoxic helium\u2013O2 breathing reduces the O2 cost of cycling and perceived exertion in obese adolescents

Purpose: In obesity, an increased work of breathing contributes to a higher O2 cost of exercise and negatively affects exercise tolerance. The purpose of the study was to determine whether, in obese adolescents, acute respiratory muscle unloading via normoxic helium\u2013O2 breathing reduces the O2 cost of cycling and perceived exertion. Methods: Nine males [age 16.8 \ub1 1.6 (x \ub1 SD) years, body mass 109.9 \ub1 15.0 kg] performed on a cycle ergometer, breathing room air (AIR) or a 21 % O2\u201379 % helium mixture (He\u2013O2): an incremental exercise, for determination of $$mathop Vlimits^{.}$$V.O2 peak and gas exchange threshold (GET); 12 min constant work rate (CWR) exercises at 70 % of GET (GET) determined in AIR. Results: $$mathop Vlimits^{.}$$V.O2 peak was not different in the two conditions. From the 3rd to the 12th minute of exercise (both during CWR GET), $$mathop Vlimits^{.}$$V.O2 was lower in He\u2013O2 vs. AIR (end-exercise values: 1.40 \ub1 0.14 vs. 1.57 \ub1 0.22 L min 121 GET). During CWR > GET in AIR, $$mathop Vlimits^{.}$$V.O2 linearly increased from the 3rd to the 12th minute of exercise, whereas no substantial increase was observed in He\u2013O2. The O2 cost of cycling was ~10 % (GET) lower in He\u2013O2 vs. AIR. Heart rate and ratings of perceived exertion for dyspnea/respiratory discomfort and leg effort were lower in He\u2013O2. Conclusions: In obese adolescents, acute respiratory muscle unloading via He\u2013O2 breathing lowered the O2 cost of cycling and perceived exertion during submaximal moderate- and heavy-intensity exercise

Effects of a multidisciplinary body weight reduction program on static and dynamic thoraco-abdominal volumes in obese adolescents

The objective of this study was to characterize static and dynamic thoraco-abdominal volumes in obese adolescents and to test the effects of a 3-week multidisciplinary body weight reduction program (MBWRP), entailing an energy-restricted diet, psychological and nutritional counseling, aerobic physical activity, and respiratory muscle endurance training (RMET), on these parameters. Total chest wall (VCW), pulmonary rib cage (VRC,p), abdominal rib cage (VRC,a), and abdominal (VAB) volumes were measured on 11 male adolescents (Tanner stage: 3-5; BMI standard deviation score: >2; age: 15.9 ± 1.3 years; percent body fat: 38.4%) during rest, inspiratory capacity (IC) maneuver, and incremental exercise on a cycle ergometer at baseline and after 3 weeks of MBWRP. At baseline, the progressive increase in tidal volume was achieved by an increase in end-inspiratory VCW (p < 0.05) due to increases in VRC,p and VRC,a with constant VAB. End-expiratory VCW decreased with late increasing VRC,p, dynamically hyperinflating VRC,a (p < 0.05), and progressively decreasing VAB (p < 0.05). After MBWRP, weight loss was concentrated in the abdomen and total IC decreased. During exercise, abdominal rib cage hyperinflation was delayed and associated with 15% increased performance and reduced dyspnea at high workloads (p < 0.05) without ventilatory and metabolic changes. We conclude that otherwise healthy obese adolescents adopt a thoracoabdominal operational pattern characterized by abdominal rib cage hyperinflation as a form of lung recruitment during incremental cycle exercise. Additionally, a short period of MBWRP including RMET is associated with improved exercise performance, lung and chest wall volume recruitment, unloading of respiratory muscles, and reduced dyspnea