Snoring and Sleep Apnea in Obese Adolescents: Effect of Long-term weight loss-Rehabilitation.

Objective: To test the effect of a long-term weight loss rehabilitation program in extremely obese adolescents on breathing parameters during sleep. Methods: Thirty-eight extremely obese [mean body mass index (BMI) 45.3 +/- 7.9kg/m(2)] adolescents participated during a three- to nine-month period in an inpatient weight loss rehabilitation in a specialized long-term rehabilitation center. Breathing parameters were registered via a seven-channel portable screening device. Body weight and arterial blood pressure were measured before and after the long-term treatment. Results: Mean BMI decreased from 45.3 to 35.8 (p < 0.001), mean diastolic blood pressure decreased from 89 mmHg to 81 mmHg (p = 0,002). Nine patients had a RDI of >/=5 and 30 patients a RDI of <5; the mean RDI decreased from 4.08 to 3.27 (n.s.). Within the group, the RDI was >/=5 and the mean RDI decreased from 10.3/h to 5.2/h (p = 0.02). The mean SaO2 increased from 93.65 to 95.35% (p = 0.003), lowest SaO2 increased from 72.14 to 73.19% (n.s.) and snoring frequency decreased from 37.56% of total sleep time (TST) to 32.86% of TST (n.s.). Conclusion: A long-term inpatient weight loss program has a positive effect on breathing parameters during sleep in extremely obese adolescents. However, the effect on apneic events and snoring is relatively minor compared to the effect on arterial oxygen saturation. The role of obesity in the origin of respiratory events and snoring in adolescents might be overestimated.

The national cholesterol education program diet vs a diet lower in carbohydrates and higher in protein and monounsaturated fat: a randomized trial.

BACKGROUND: In the United States, obesity is a major clinical and public health problem causing diabetes, dyslipidemia, and hypertension, as well as increasing cardiovascular and total mortality. Dietary restrictions of calories and saturated fat are beneficial. However, it remains unclear whether replacement of saturated fat with carbohydrates (as in the US National Cholesterol Education Program [NCEP] diet) or protein and monounsaturated fat (as in our isocaloric modified low-carbohydrate [MLC] diet, which is lower in total carbohydrates but higher in protein, monounsaturated fat, and complex carbohydrates) is optimal. METHODS: We randomized 60 participants (29 women and 31 men) to the NCEP or the MLC diet and evaluated them every 2 weeks for 12 weeks. They were aged 28 to 71 years (mean age, 44 years in the NCEP and 46 years in the MLC group). A total of 36% of participants from the NCEP group and 35% from the MLC group had a body mass index (calculated as weight in kilograms divided by the square of height in meters) greater than 27. The primary end point was weight loss, and secondary end points were blood lipid levels and waist-to-hip ratio. RESULTS: weight loss was significantly greater in the MLC (13.6 lb) than in the NCEP group (7.5 lb), a difference of 6.1 lb (P = .02). There were no significant differences between the groups for total, low density, and high-density lipoprotein cholesterol, triglycerides, or the proportion of small, dense low-density lipoprotein particles. There were significantly favorable changes in all lipid levels within the MLC but not within the NCEP group. Waist-to-hip ratio was not significantly reduced between the groups (P = .27), but it significantly decreased within the MLC group (P = .009). CONCLUSIONS: Compared with the NCEP diet, the MLC diet, which is lower in total carbohydrates but higher in complex carbohydrates, protein, and monounsaturated fat, caused significantly greater weight loss over 12 weeks. There were no significant differences between the groups in blood lipid levels, but favorable changes were observed within the MLC diet group.

Do baseline serum leptin levels predict weight regain after dieting in obese women?

AIM: weight loss achieved during weight reduction programme is difficult to maintain. We investigated the possible role of circulating leptin in failure or success in maintaining weight loss. METHODS: Serum leptin levels were measured in 30 healthy premenopausal obese women before and after 12 weeks of dietary intervention and after 5 months of follow-up. RESULTS: After intervention body mass index (BMI) decreased from 30.6 to 25.4 kg/m2 (p < 0.01) and leptin levels decreased from 16.7 to 7.7 ng/ml (p < 0.01). After 5 months follow-up 12 women regained reduced weight and 18 women maintained weight loss. In the regainers leptin levels increased again, but remained low in the maintainers. Baseline leptin concentrations were lower in the regainers than in the maintainers (12.1 vs. 21.2 ng/ml, p = 0.04). During intervention leptin levels decreased three times more in the maintainers than in the regainers, although weight loss was similar in both groups. CONCLUSIONS: This study shows that obese women who regain weight after dieting have significantly lower baseline leptin levels than women who maintain weight loss. Our results suggest that differences in leptin resistance might exist in similarly obese women which could influence the success of dieting.

Relationship between single nucleotide polymorphisms in leptin, IL6 and adiponectin genes and their circulating product in morbidly obese subjects before and after gastric banding surgery.

BACKGROUND: Certain adipose-produced signals are secreted in proportion to body fat mass and are involved in regulation of the energy metabolism of the whole body. Leptin, IL6 and adiponectin can be considered as adiposity signals. Several Single Nucleotide Polymorphisms (SNPs) in genes encoding for these molecules are known to influence their concentration in situations of stable weight. We hypothesized that polymorphism effects could be better detected in a situation of negative energy balance and that modified concentrations of adiposity signal genes could change the dynamics of weight gain in obese subjects. METHODS: 65 obese patients undergoing gastric banding surgery were genotyped for LEP+19A-->G, LEP-2548G-->C, IL6-174G-->C, APM1-11377C-->G and PM1-11391G-->A common SNPs. BMI and concentrations of leptin, IL6 and adiponectin were measured before surgery and after 1 year. RESULTS: All SNPs except IL6-174G-->C SNP were associated with modifications of the circulating concentrations of signals produced by adipose tissue at baseline. During weight loss, variant genotype carriers of LEP -2548 and +19 SNPs were characterized by a trend towards less decrease in circulating leptin. weight loss was associated with an increase in IL6 concentration (16.9%+/-12.2) in the IL6-174 C/C genotype carriers, whereas the C/G or G/G genotypes carriers showed a decrease in IL6 (19.9%+/-5.2, P=0.001). CONCLUSION: We observed that the SNPs studied could modulate the concentration of adiposity signals not only at baseline but also during weight loss. Such variations may be sensed by the homeostatic feedback system that controls energy balance and may in turn contribute to some disturbances in weight regulation.

Adolescent binge/purge and weight loss behaviors: associations with developmental assets.

PURPOSE: To study associations between binge/purge and weight loss behaviors and "developmental assets" among adolescent girls and boys. METHODS: The Search Institute's Profile of Student Life: Attitudes and Behaviors self-report questionnaire was administered to 48,264 girls and 47,131 boys in grades 6 through 12 at schools in 213 cities or towns across the United States. The 156-item questionnaire measured 40 "developmental assets," or protective factors associated with successful adolescent development. Developmental assets were examined using multiple logistic regression among students who reported binge/purge behaviors, weight loss behavior, both, or neither. RESULTS: Developmental assets related to positive identity were the strongest discriminators of binge/purge and weight loss behaviors in both girls and boys. Girls who reported binge/purge and weight loss behaviors were about half as likely to report feeling a sense of purpose [odds ratio (OR) = 0.45, 95% confidence interval (CI) = 0.40, 0.50] and high self-esteem (OR = 0.55, 95% CI = 0.49, 0.61), compared with girls not reporting either of these behaviors. Among boys the ORs were: sense of purpose OR = 0.53 (95% CI = 0.46, 0.61) and self-esteem OR = 0.76 (95% CI = 0.65, 0.88). Assets related to values about abstinence from alcohol, drugs, or sex ("restraint") were also significant correlates. Girls and boys who reported these values were less likely to report binge/purge and weight loss behaviors, compared with those who did not report these values (girls: OR = 0.56, 95% CI = 0.50, 0.63; boys: OR = 0.83, 95% CI = 0.70, 0.97). CONCLUSIONS: Internal assets such as self-esteem, sense of purpose, and values related to abstinence from alcohol and sex appear to be protective against unhealthy eating behaviors and may reflect a general resilience that buffers against a broad range of health risk behaviors.

Effect of significant intermediate-term weight loss on serum leptin levels and body composition in severely obese subjects.

BACKGROUND: Leptin, produced by adipose tissue, signals body fat content to the hypothalamus. Serum leptin levels (SLL), elevated in obese humans, decrease with weight loss. This study investigated the reduction of SLL and fat mass following restrictive bariatric surgery. METHODS: Obese subjects (body mass index [BMI] >35 kg/m2, n=154) undergoing gastric banding (weight-reduced subjects) were investigated for SLL and body composition before surgery and for 2 years after. Overweight subjects matched for fat mass and gender (fat mass-matched overweight controls, n=194) and subjects who had never been obese (normal weight controls, n=158) were studied for comparison. RESULTS: SLL were highest in weight-reduced subjects and decreased with weight loss (P <0.001), remaining elevated compared with normal weight controls (P <0.001) but lower than fat mass-matched overweight controls (women: P <0.04). At 2 years, SLL normalized for fat mass (allowing comparison between various levels of adiposity) were lower in weight-reduced subjects compared with fat mass-matched overweight controls (women: P =0.003), yet were similar for weight-reduced subjects at 2 years compared with normal weight controls despite 14 kg greater fat mass. Relative lean mass of extremities in weight-reduced subjects increased with weight loss (P <0.001). CONCLUSION: SLL decreased after considerable weight loss more than could be accounted for by fat mass or BMI reduction alone. This disproportionate decrease in SLL might point to a mechanism that evolved as adaptation to starvation during times of famine. Thus, post-obese subjects may be at risk of weight-regain due to disproportionately low SLL and increased appetite via the leptin-melanocortin pathway.

Primary care weight management counseling: physician and patient perspectives.

This paper examines the use of the Guide to Clinical Preventive Services for behavioral counseling for overweight patients in the primary care setting. METHODS: Study 1 assessed counseling practices of family physicians with a 13-item physician questionnaire based on the Guide to Clinical Preventive Services. Study 2 assessed the perception of weight loss recommendations made to obese primary care patients attending a family practice clinic. RESULTS: 46% of the family physicians responded. The most common referrals were made to dieticians and exercise programs. The patient survey indicated that 80.3% had received weight loss recommendations, and 68.9% had received counseling on diet change or exercise. CONCLUSIONS: This study found adequate rates of compliance with the Guide to Clinical Preventive Services. However, these results have highlighted the need to expand the guidelines to counsel patients more specifically with regard to weight loss recommendations and to focus on improving patient compliance and motivation.

Predictors of complication and suboptimal weight loss after laparoscopic Roux-en-Y gastric bypass: a series of 188 patients.

HYPOTHESIS: An analysis of patients undergoing laparoscopic Roux-en-Y gastric bypass (RYGB) may identify factors predictive of complication and of suboptimal weight loss. DESIGN: Inception cohort. SETTING: Metropolitan university hospital. PATIENTS: One hundred eighty-eight consecutive patients with severe obesity who met National Institutes of Health consensus guidelines for bariatric surgery. INTERVENTIONS: Laparoscopic RYGB. MAIN OUTCOME MEASURES: Complications requiring therapeutic intervention and percentage of excess body weight lost at 1 year after surgery. RESULTS: Of the 188 patients who underwent laparoscopic RYGB, 50 (26.6%) developed complications that required an invasive therapeutic intervention, including 2 deaths. The average follow-up was 351 days (range, 89-1019 days). Multivariate analysis by stepwise logistic regression identified surgeon experience, sleep apnea (P =.003; odds ratio, 3.0; 95% confidence interval, 1.3-7.1), and hypertension (P =.07; odds ratio, 2.0; 95% confidence interval, 1.0-4.0) as predictors of complications. The most common complication requiring therapeutic intervention was stricture at the gastrojejunal anastomosis, occurring in 27 patients (14.4%). Of the 115 patients who underwent surgery more than 1 year previously, 1-year follow-up data were available for 93 (81%). The body mass index (weight in kilograms divided by the square of height in meters) decreased from 53 +/- 8 preoperatively to 35 +/- 6 at 1 year. The mean +/- SD percentage of excess body weight lost at 1 year was 61% +/- 14%. Diabetes mellitus was negatively correlated with percentage of excess body weight lost at 1 year (P =.06). CONCLUSIONS: Surgeon experience, sleep apnea, and hypertension are associated with complications after laparoscopic RYGB. Diabetes mellitus may be associated with poorer postoperative weight loss.