Evaluation of a community-based weight management program for predominantly severely obese, difficult-to-reach, inner-city minority adolescents.

BACKGROUND: Few interventions targeting severely obese minority youth have been implemented in community-based settings. We evaluate a 9-month multicomponent, community-based program for obese, inner-city adolescents. METHODS: Of 5250 estimated eligible adolescents, 349 were recruited; they had a mean age of 15 ± 2 years, mean BMI %ile 98.9 ± 1.5, and comprised 52% African American and 44% Hispanic. Longitudinal trends of anthropometric measures were compared 1 year before enrollment (T-12), at baseline (T0) and after program completion (T9). Dietary and physical activity behaviors were compared at T0 and T9. Anthropometric changes were compared at T9 and 18 months (T18) in completers and noncompleters. RESULTS: A majority of participants were severely obese (67%) and expressed low readiness to change behaviors (82%). For intervals T-12 to T0 versus T0 to T9, there were significant decreases in rates of gain in BMI (0.13 vs. 0.04, p < 0.01), BMI percentile (0.0002 vs. -0.0001, p < 0.01), percent overweight (0.001 vs. -0.001, p < 0.01), and BMI z-score (0.003 vs. -0.003, p < 0.01). Significant increases in vegetable and fruit consumption and in vigorous physical activity participation were observed. From T9 to T18, except for a significant increase in BMI (38.3 ± 7.4 vs. 39.0 ± 7.5, p < 0.01) in completers, all other anthropometric measures remained unchanged in completers and noncompleters. CONCLUSIONS: We demonstrate modest clinical improvements and increased healthy lifestyle behaviors in predominantly severely obese, difficult-to-reach, ethnic minority adolescents attending a community-based weight management program. The loss of clinical improvements 9 months after program completion implies that extending the duration of such a program may prevent long-term weight regain in severely obese adolescents.

Adenotonsillectomy in obese children with obstructive sleep apnea syndrome: magnetic resonance imaging findings and considerations.

OBJECTIVE: The reasons why adenotonsillectomy (AT) is less effective treating obese children with obstructive sleep apnea syndrome (OSAS) are not understood. Thus, the aim of the study was to evaluate how anatomical factors contributing to airway obstruction are affected by AT in these children. METHODS: Twenty-seven obese children with OSAS (age 13.0 ± 2.3 y, body mass index Z-score 2.5 ± 0.3) underwent polysomnography and magnetic resonance imaging of the head during wakefulness before and after AT. Volumetric analysis of the upper airway and surrounding tissues was performed using commercial software (AMIRA®). RESULTS: Patients were followed for 6.1 ± 3.6 mo after AT. AT improved mean obstructive apnea-hypopnea index (AHI) from 23.7 ± 21.4 to 5.6 ± 8.7 (P < 0.001). Resolution of OSAS was noted in 44% (12 of 27), but only in 22% (4 of 18) of those with severe OSAS (AHI > 10). AT increased the volume of the nasopharynx and oropharynx (2.9 ± 1.3 versus 4.4 ± 0.9 cm(3), P < 0.001, and 3.2 ± 1.2 versus 4.3 ± 2.0 cm(3), P < 0.01, respectively), reduced tonsils (11.3 ± 4.3 versus 1.3 ± 1.4 cm(3), P < 0.001), but had no effect on the adenoid, lingual tonsil, or retropharyngeal nodes. A small significant increase in the volume of the soft palate and tongue was also noted (7.3 ± 2.5 versus 8.0 ± 1.9 cm(3), P = 0.02, and 88.2 ± 18.3 versus 89.3 ± 24.4 cm(3), P = 0.005, respectively). CONCLUSIONS: This is the first report to quantify volumetric changes in the upper airway in obese children with OSAS after adenotonsillectomy showing significant residual adenoid tissue and an increase in the volume of the tongue and soft palate. These findings could explain the low success rate of AT reported in obese children with OSAS and are important considerations for clinicians treating these children.

Sleep and cardiometabolic function in obese adolescent girls with polycystic ovary syndrome.

OBJECTIVE: To compare the polysomnography findings and cardiometabolic function among adolescent girls with polycystic ovary syndrome (PCOS) and matched female and male controls. METHOD: Retrospective chart review of electronic medical records of 28 girls with PCOS (age: 16.8±1.9 years, body mass index (BMI) Z-score 2.4±0.4), 28 control females (age: 17.1±1.8, BMI Z-score 2.4±0.3) and 28 control males (age: 16.6±1.6, BMI Z-score 2.5±0.5) in a tertiary care centre. RESULTS: The prevalence of obstructive sleep apnoea (OSA) was higher in girls with PCOS compared to control females (16/28 (57%) vs. 4/28(14.3%), p<0.01); however, it was comparable to that of the control males (16/28(57%) vs. 21/28(75%), p=0.4). Girls with PCOS had a significantly higher prevalence of insulin resistance compared to control females and control males (20/28 (71.4%) vs. 9/22 (41.0%) (p=0.04) vs. 8/23 (34.8%) (p=0.01). Among girls with PCOS, those with OSA had significantly higher proportions of metabolic syndrome (MetS) (9/16 (56.3%) vs. 1/12 (8.3%) p=0.03), higher insulin resistance (14/16 (87.5%) vs. 6/12 (50%), p=0.04), elevated daytime systolic blood pressure (128.4±12.8 vs. 115.6±11.4, p<0.01), lower high-density lipoprotein (HDL) (38.6±8.7 vs. 49±10.9, p=0.01) and elevated triglycerides (TG) (149.7±87.7 vs. 93.3±25.8, p=0.03) compared to those without OSA. CONCLUSIONS: We report a higher prevalence of OSA and metabolic dysfunction in a selected group of obese girls with PCOS referred with sleep-related complaints compared to BMI-matched control girls without PCOS. We also report higher prevalence of cardiometabolic dysfunction in girls with PCOS and OSA compared to girls with PCOS without OSA.

Upper airway lymphoid tissue size in children with sickle cell disease.

BACKGROUND: The prevalence of obstructive sleep apnea syndrome (OSAS) is higher in children with sickle cell disease (SCD) as compared with the general pediatric population. It has been speculated that overgrowth of the adenoid and tonsils is an important contributor. METHODS: The current study used MRI to evaluate such an association. We studied 36 subjects with SCD (aged 6.9 ± 4.3 years) and 36 control subjects (aged 6.6 ± 3.4 years). RESULTS: Compared with control subjects, children with SCD had a significantly smaller upper airway (2.8 ± 1.2 cm(3) vs 3.7 ± 1.6 cm(3), P < .01), and significantly larger adenoid (8.4 ± 4.1 cm(3) vs 6.0 ± 2.2 cm(3), P < .01), tonsils (7.0 ± 4.3 cm(3) vs 5.1 ± 1.9 cm(3), P < .01), retropharyngeal nodes (3.0 ± 1.9 cm(3) vs 2.2 ± 0.9 cm(3), P < .05), and deep cervical nodes (15.7 ± 5.7 cm(3) vs 12.7 ± 4.0 cm(3), P < .05). Polysomnography showed that 19.4% (seven of 36) of children with SCD had OSAS compared with 0% (zero of 20) of control subjects (P < .05) and that in children with SCD the apnea-hypopnea index correlated positively with upper airway lymphoid tissues size (r = 0.57, P < 001). In addition, children with SCD had lower arterial oxygen saturation nadir (84.3% ± 12.3% vs 91.2% ± 4.2%, P < .05), increased peak end-tidal CO(2) (53.4 ± 8.5 mm Hg vs 42.3 ± 5.3 mm Hg, P < .001), and increased arousals (13.7 ± 4.7 events/h vs 10.8 ± 3.8 events/h, P < .05). CONCLUSIONS: Children with SCD have reduced upper airway size due to overgrowth of the surrounding lymphoid tissues, which may explain their predisposition to OSAS.

Screening for sleep-disordered breathing and excessive daytime sleepiness in adolescent girls with polycystic ovarian syndrome.

OBJECTIVE: To determine the prevalence and clinical and metabolic correlates of sleep-disordered breathing (SDB) and excessive daytime sleepiness (EDS) in adolescent girls with polycystic ovarian syndrome (PCOS). STUDY DESIGN: Standardized questionnaires were administered to participants with PCOS and age-, sex-, ethnicity-, and body mass index (BMI) z score-matched controls. Medical records were reviewed for anthropometric and metabolic data. RESULTS: We studied 103 participants with PCOS (16.9 ± 1.5 years) and 90 controls (16.8 ± 1.7 years). Compared with controls, girls with PCOS had a higher prevalence of SDB (45.6% vs 27.8%; P = .01) and EDS (54.4% vs 35.6%; P < .01). Within PCOS, those with SDB had higher BMI z score (2.1 ± 0.5 vs 1.7 ± 0.6; P < .01), higher homeostatic model assessment index (5.1 ± 2.3 vs 4.1 ± 3.5; P < .01), and higher prevalence of the metabolic syndrome (MetS) (42.6% vs 16.1%; P = .003) compared with those without SDB. Similarly, participants with PCOS and EDS had a higher BMI z score (2.0 ± 0.6 vs 1.7 ± 0.6; P = .03), higher homeostatic model assessment index (5.1 ± 2.9 vs 3.8 ± 3.1; P = .01), and higher rate of MetS (39.3% vs. 14.9%; P < .01) compared with those without EDS. MetS was independently associated with SDB (OR, 3.2; 95% CI, 1.0-10.1) and EDS (OR, 4.5; 95% CI, 1.2-16). CONCLUSIONS: SDB and EDS are highly prevalent in adolescent girls with PCOS compared with matched controls. The MetS is independently associated with SDB and EDS in this group.

Prediction of protein loop geometries in solution.

The ability to determine the structure of a protein in solution is a critical tool for structural biology, as proteins in their native state are found in aqueous environments. Using a physical chemistry based prediction protocol, we demonstrate the ability to reproduce protein loop geometries in experimentally derived solution structures. Predictions were run on loops drawn from (1)NMR entries in the Protein Databank (PDB), and from (2) the RECOORD database in which NMR entries from the PDB have been standardized and re-refined in explicit solvent. The predicted structures are validated by comparison with experimental distance restraints, a test of structural quality as defined by the WHAT IF structure validation program, root mean square deviation (RMSD) of the predicted loops to the original structural models, and comparison of precision of the original and predicted ensembles. Results show that for the RECOORD ensembles, the predicted loops are consistent with an average of 95%, 91%, and 87% of experimental restraints for the short, medium and long loops respectively. Prediction accuracy is strongly affected by the quality of the original models, with increases in the percentage of experimental restraints violated of 2% for the short loops, and 9% for both the medium and long loops in the PDB derived ensembles. We anticipate the application of our protocol to theoretical modeling of protein structures, such as fold recognition methods; as well as to experimental determination of protein structures, or segments, for which only sparse NMR restraint data is available.