A dissonance-based intervention for women post roux-en-Y gastric bypass surgery aiming at improving quality of life and physical activity 24 months after surgery: study protocol for a randomized controlled trial.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) surgery is the most common bariatric procedure in Sweden and results in substantial weight loss. Approximately one year post-surgery weight regain for these patient are common, followed by a decrease in health related quality of life (HRQoL) and physical activity (PA). Our aim is to investigate the effects of a dissonance-based intervention on HRQoL, PA and other health-related behaviors in female RYGB patients 24 months after surgery. We are not aware of any previous RCT that has investigated the effects of a similar intervention targeting health behaviors after RYGB. METHODS: The ongoing RCT, the "WELL-GBP"-trial (wellbeing after gastric bypass), is a dissonance-based intervention for female RYGB patients conducted at five hospitals in Sweden. The participants are randomized to either control group receiving usual follow-up care, or to receive an intervention consisting of four group sessions three months post-surgery during which a modified version of the Stice dissonance-based intervention model is used. The sessions are held at the hospitals, and topics discussed are PA, eating behavior, social and intimate relationships. All participants are asked to complete questionnaires measuring HRQoL and other health-related behaviors and wear an accelerometer for seven days before surgery and at six months, one year and two years after surgery. The intention to treat and per protocol analysis will focus on differences between the intervention and control group from pre-surgery assessments to follow-up assessments at 24 months after RYGB. Patients' baseline characteristics are presented in this protocol paper. DISCUSSION: A total of 259 RYGB female patients has been enrolled in the "WELL-GBP"-trial, of which 156 women have been randomized to receive the intervention and 103 women to control group. The trial is conducted within a Swedish health care setting where female RYGB patients from diverse geographical areas are represented. Our results may, therefore, be representative for female RYGB patients in the country as a whole. If the intervention is effective, implementation within the Swedish health care system is possible within the near future. TRIAL REGISTRATION: The trial was registered on February 23th 2015 with registration number ISRCTN16417174 .

Assessment of change in body fat percentage with DXA and eight-electrode BIA in centrally obese women.

PURPOSE: To compare estimates of change in percent body fat (Delta%BF) between DXA and BIA8 in abdominally obese women. METHODS: Six-month longitudinal study of 106 women (baseline: age 48.2 +/- 7.6 yr; BMI 30.4 +/- 2.9 kg.m; %BFDXA 45.8 +/- 3.6%) participating in an exercise-oriented behavior-change program (walking and bicycling). Fatness was measured by DXA and Tanita BC-418 (BIA8). Agreement between methods was assessed, and regression analysis was used to find predictors of the deviation between methods for estimating changes in fat mass percentage. RESULTS: The methods differed significantly, both at baseline and follow-up (-5.0 and -4.4%BF, respectively; both P < 0.001). The mean Delta%BF was -1.1 +/- 2.5%BFDXA and -0.5 +/- 2.2%BFBIA8 (mean difference between methods 0.6 +/- 1.8%BF; P < 0.001; 95% limits of agreement -3.0 to 4.2%BF), with a range of -14.8 to 3.3%BFDXA and -9.4 to 3.5%BFBIA8. Approximately 49% of the variation in the difference between methods was explained by variations in age (beta = -0.05; P = 0.006), DeltaBMI (beta = 0.98; P < 0.001), and Delta%BFDXA (beta = -0.71; P < 0.001), indicating that the larger the change, the greater the discrepancy between methods. CONCLUSION: The difference between methods regarding Delta%BF was statistically significant, but it was of small magnitude. However, with increasing Delta%BF, increasing discrepancies were observed, implying that the BIA equipment may have limited validity for detecting larger fat losses. Both clinicians and researchers may benefit from awareness of this potential limitation.

Changes in BMI and psychosocial functioning in partners of women who undergo gastric bypass surgery for obesity.

BACKGROUND: There is very little research exploring the effects of Roux-en-Y gastric bypass surgery (RYGB) on the patient's partner. The aim of the present study was to investigate longitudinally whether male partners of female RYGB patients were affected in terms of BMI, sleep quality, body dissatisfaction, depression, and anxiety. METHODS: Thirty-seven women, with partners who were willing to participate, were recruited from RYGB waiting lists at five Swedish hospitals. Data collection took place during two home visits, 3 months before and 9 months after RYGB surgery. Anthropometrical data were documented, and both women and men completed the Hospital Anxiety and Depression Scale (HADS) and the Karolinska Sleep Questionnaire (KSQ). The men also completed the Male Body Dissatisfaction Scale (MBDS). RESULTS: The men's BMI changes between the two time points that were analysed using general estimating equation (GEE) regression. Their BMI decreased significantly (ß = -0.9, p = 0.004). The change was more pronounced in the 26 men who had a baseline BMI of ≥25 (ß = -1.4, p < 0.001). Fixed-effects regression showed a statistically significant association between the men's weight loss and that of the women (ß = 0.3, p = 0.004). There were no significant changes in the men's HADS, KSQ, or MBDS scores. CONCLUSIONS: Overweight/obese male partners of RYGB patients also lose weight during the first 9 months post-operatively. However, symptoms of body dissatisfaction, anxiety, and depression remain unchanged, as does self-reported sleep quality.

Longitudinal assessment of physical activity in women undergoing Roux-en-Y gastric bypass.

BACKGROUND: Patients undergoing bariatric surgery do not seem to increase objectively measured physical activity (PA) after surgery, despite substantial weight loss. The aims of the present study were (i) to objectively characterize 3 months pre-surgery to 9 months postsurgery PA and sedentary behavior changes in women undergoing Roux-en-Y gastric bypass (RYGB) using tri-axial accelerometers and (ii) to examine associations between pre-surgery versus postsurgery PA and sedentary behavior with anthropometric measures taken in home environment. METHODS: Fifty-six women, with an average pre-surgery body mass index (BMI) of 37.6 (SD 2.6) and of age 39.5 years (SD 5.7), were recruited at five Swedish hospitals. PA was measured for 1 week by the Actigraph GT3X+ accelerometer, and anthropometric measures were taken at home visits 3 months pre-surgery and 9 months postsurgery, thus limiting seasonal effects. RESULTS: Average BMI loss, 9 months postsurgery, was 11.7 (SD 2.7) BMI units. There were no significant pre- to postsurgery differences in PA or sedentary behavior. However, pre-surgery PA showed negative association with PA change and positive association with postsurgery PA. Adjustments for pre-surgery BMI had no impact on these associations. CONCLUSIONS: No significant differences were observed in objectively measured changes in PA or time spent sedentary from 3 months pre-surgery to 9 months postsurgery among women undergoing RYGB. However, women with higher pre-surgery PA decreased their PA postsurgery while women with lower pre-surgery PA increased their PA.

Bicycling but not walking is independently associated with fasting insulin in abdominally obese women.

BACKGROUND: The impact of walking and bicycling on insulin resistance (IR) in women with abdominal obesity is unclear. METHODS: Pooled analysis of data from a randomized trial on physically active commuting (bicycling + walking vs walking only) in women with abdominal obesity [n = 98; age:47.3 ± 7.6 yrs; waist circumference (WC):103.1 ± 7.8 cm]. Bicycling and walking data were collected during 7 consecutive days by trip meters (Trelock FC-410) and pedometers (Yamax digiwalker SW-200) at baseline, 2, 4, and 6 months. Owing to a skew distribution we analyzed bicycling as a binary dummy variable with a 10 km/week cut-off. Fasting serum insulin and homeostatic model assessment - insulin resistance (HOMA-IR) were assessed at baseline and 6 months, as were body mass index (BMI), WC, and dual x-ray absorptiometry (DXA)-assessed % whole-body fat. RESULTS: Increased bicycling by 10 km/wk was associated with reductions in fasting serum insulin at follow-up independent of age, treatment allocation, baseline phenotype, Δ walking, and Δ % body fat (ß = -10.9, P = .042), but not HOMA-IR (ß = -2.0, P = .13). Increased walking was not associated with fasting serum insulin (P = .33) or HOMA-IR (P = .44) at follow-up, after adjustment for the same covariates and Δ bicycling. CONCLUSION: Increased bicycling but not walking was associated with reduced insulin levels at follow-up. Bicycling may be more effective than walking for reducing insulin levels in abdominally obese women.

Impact of physical activity and body composition on heart function and morphology in middle-aged, abdominally obese women.

Several studies have shown training induced morphological changes in the heart. Our aim was to assess how frequent, low-intensity exercise (walking and cycling) influences heart function and morphology in abdominally obese women. Fifty women with abdominal obesity (mean age 47.0 +/- 7.5 years, waist circumference (WC) 103.2 +/- 7.8 cm), free of cardiovascular problems were recruited. They were equipped with a bicycle and pedometers and instructed to start commuting in a physically active way for 6 months. Evaluation of cardiac function and morphology was performed using echocardiography (ECHO) before and after 6 months of training. The subjects increased significantly their daily physical activity. After 6 months, there was a significant decrease in WC (from 103.3 +/- 7.9 to 100.8 +/- 8.4 cm, P = 0.0003), in systolic and diastolic blood pressure (126.8 +/- 15.2 to 120.4 +/- 14.5 mmHg, P = 0.0001, and 79.8 +/- 7.8 to 77.8 +/- 8.4 mmHg, P = 0.0006, respectively). ECHO showed an increase in the right ventricular (RV) systolic longitudinal function expressed as tricuspid annular motion from 22.00 +/- 3.30 to 23.05 +/- 3.59 mm, P = 0.015; and a similar trend in left ventricular (LV) mitral annular motion, which increased from 13.09 +/- 1.53 to 13.39 +/- 1.47 mm, P = 0.070. Cycling was associated with reductions in LV systolic and RV diastolic dimensions, whereas walking was not associated with any changes in the ECHO-variables. A reduction in WC by frequent, low-intensity exercise in abdominally obese women is associated with decrease in blood pressure and improved longitudinal RV systolic function.

A two-year weight reduction program in obese sleep apnea patients.

STUDY OBJECTIVES: To evaluate the effects of a 2-year weight reduction program on respiratory disturbances, arousal index, daytime sleepiness, metabolic status, and quality of life in obese patients with obstructive sleep apnea syndrome (OSAS). METHODS: Prospective intervention study of 33 consecutive obese OSAS patients (24 men, 9 women); 19 subjects used continuous positive airway pressure and 4 used mandibular retaining device, except during nights with sleep recording. The program consisted of 8 weeks of low calorie diet followed by group meetings with behavioral change support. RESULTS: Seventy percent of the patients completed the program; 67% completed the sleep recordings. The success rate for the apnea-hypopnea index (AHI) (< 20 and reduction > or = 50%) was 15% in the intention to treat (ITT) analysis. The AHI showed a nonsignificant decrease in mean values, from 43 to 28. The oxygen desaturation index (ODI) decreased from 42 to 23 (p = 0.010), arousal index from 24 to 11 (p = 0.019), body mass index from 40 to 35 (p = 0.003) and the Epworth Sleepiness Scale (ESS) from 9 to 5 (p = 0.026), all ITT. Metabolic status, physical functioning, and vitality evaluations improved only in the per protocol analysis. Reduction in weight correlated significantly to reductions in ESS (p = 0.038) and insulin levels (p = 0.002), respectively. There were no differences based on gender or use/non-use of OSAS treatment device. CONCLUSIONS: Our weight reduction program showed a limited success in reducing AHI. However, there were significant improvements in weight, ODI, arousal index, and subjective symptoms. We recommend the program as an adjunct treatment for well-motivated obese OSAS patients.

No apparent progress in bioelectrical impedance accuracy: validation against metabolic risk and DXA.

Bioelectrical impedance (BIA) is quick, easy, and safe when quantifying fat and lean tissue. New BIA models (Tanita BC-418 MA, abbreviated BIA(8)) can perform segmental body composition analysis, e.g., estimate %trunkal fatness (%TF). It is not known, however, whether new BIA models can detect metabolic risk factors (MRFs) better than older models (Tanita TBF-300, abbreviated BIA(4)). We therefore tested the correlation between MRF and percentage whole-body fat (%BF) from BIA(4) and BIA(8) and compared these with the correlation between MRF and dual-energy X-ray absorptiometry (DXA, used as gold standard), BMI and waist circumference (WC). The sample consisted of 136 abdominally obese (WC >or= 88 cm), middle-aged (30-60 years) women. MRF included fasting blood glucose and insulin; high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides; high sensitive C-reactive protein, plasminogen activator inhibitor-1 (PAI-1), and fibrinogen; and alanine transaminase (ALT) liver enzyme. We found that similar to DXA, but in contrast to BMI, neither %BF BIA(4) nor %BF BIA(8) correlated with blood lipids or ALT. In the segmental analysis of %TF, BIA(8) only correlated with inflammatory markers, but not insulin, blood lipids, or ALT liver enzyme (in contrast to WC and %TF DXA). %TF DXA was associated with homeostatic model assessment insulin resistance (HOMA-IR) independently of WC (P = 0.03), whereas %TF BIA(8) was not (P = 0.53). Receiver-operating characteristic (ROC) curves confirmed that %TF BIA(8) did not differ from chance in the detection of insulin resistance (P = 0.26). BIA estimates of fatness were, at best, weakly correlated with obesity-related risk factors in abdominally obese women, even the new eight-electrode model. Our data support the continued use of WC and BMI.

Weight reduction improves nocturnal respiration in obese sleep apnoea patients-A randomized controlled pilot study.

OBJECTIVES: Randomized controlled pilot study of the effect of weight reduction on nocturnal respiratory parameters in obese patients with obstructive sleep apnoea syndrome (OSAS). METHODS: Twenty consecutive obese male patients fulfilling OSAS criteria at Karolinska University Hospital were randomized into two groups. Intervention with an 8-week weight reduction programme consisting of a low-calorie diet, together with group meetings, was evaluated compared to expectancy alone for the control group, followed by a crossover. Follow-up at 3 months included anthropometrics and ambulant sleep apnoea recordings. RESULTS: Eleven of twenty men completed the protocol. There were significant differences between the intervention group (n = 6) and the control group (n = 5) in changes of weight (p < 0.01) and oxygen desaturation index (ODI4) (p < 0.05). We also found a significant positive correlation in these 11 males after the crossover between their reduction in weight and their reduction in ODI4 (p < 0.05). CONCLUSIONS: This pilot study indicates that weight reduction improves nocturnal respiration in obese OSAS patients after 3 months' dietary treatment compared to expectancy.

Weight reduction improves sleep, sleepiness and metabolic status in obese sleep apnoea patients.

METHOD: In this prospective intervention study, 33 obese patients with obstructive sleep apnoea syndrome (OSAS) (24 men, 9 women) were consecutively enrolled for a weight reduction program at the Obesity Unit, Karolinska University Hospital. 23 of 33 patients used OSAS-device, 19 with Continuous Positive Airway Pressure and 4 with Mandibular Retaining Device. The patients were investigated with questionnaires, blood tests and ambulant nocturnal polysomnography before and after a 6-month program. Patients with OSAS-device slept without it during the sleep studies. The intervention consisted of 8 weeks low calorie diet and group meetings, followed by a day-care program of behaviour change support. RESULTS: 27 of 33 patients (82%, 21 men and 6 women) completed the study. After the intervention there were highly significant decreases (p < 0.001) in Body Mass Index from mean(S.D.) 40(5) to 34(3), apnoea-hypopnoea index from 43(24) to 26(20) and Epworth Sleepiness Scale (ESS)-score from 9(4) to 6(4). Sleep quality (arousal index, sleep efficiency, percentage deep sleep) and metabolic status (blood pressure, blood glucose levels, lipidemia) were also significantly improved. There was a significant correlation between increased percentage deep sleep and reduced ESS-score. There were no differences due to gender or use/no use of OSAS-device. CONCLUSION: The results suggest that weight loss, induced by low calorie diet and behaviour change support, significantly improves nocturnal respiratory parameters, sleep quality, daytime sleepiness and metabolic status in obese OSAS patients after 6 months.

Bioelectrical impedance underestimates total and truncal fatness in abdominally obese women.

OBJECTIVE: To compare estimates of total and truncal fatness from eight-electrode bioelectrical impedance analysis equipment (BIA(8)) with those from DXA in centrally obese women. The secondary aim was to examine BMI and waist circumference (WC) as proxy measures for percentage total body fat (%TBF) and truncal body fat percentage (tr%BF). RESEARCH METHODS AND PROCEDURES: This was a cross-sectional study of 136 women (age, 48.1 +/- 7.7 years; BMI, 30.4 +/- 2.9 kg/m(2); %TBF(DXA), 46.0 +/- 3.7%; WC, 104 +/- 8 cm). Fatness was measured by DXA and Tanita BC-418 equipment (Tanita Corp., Tokyo, Japan). Agreement among methods was assessed by Bland-Altman plots, and regression analysis was used to evaluate anthropometric measures as proxies for total and abdominal fatness. RESULTS: The percentage of overweight subjects was 41.9%, whereas 55.9% of the subjects were obese, as defined by BMI, and all subjects had a WC exceeding the World Health Organization cut-off point for abdominal obesity. Compared with DXA, the BIA(8) equipment significantly underestimated total %BF (-5.0; -3.6 to -8.5 [mean; 95% confidence interval]), fat mass (-3.6; -3.9 to -3.2), and tr%BF (-8.5; -9.1 to -7.9). The discrepancies between the methods increased with increasing adiposity for both %TBF and tr%BF (both p < 0.001). Variation in BMI explained 28% of the variation in %TBF(DXA) and 51% of %TBF(BIA8). Using WC as a proxy for truncal adiposity, it explained only 18% of tr%BF(DXA) variance and 27% of tr%BF(BIA8) variance. The corresponding figures for truncal fat mass were 49% and 35%, respectively. No significant age effects were observed in any of the regressions. DISCUSSION: BIA(8) underestimated both total and truncal fatness, compared with DXA, with higher dispersion for tr%BF than %TBF. The discrepancies increased with degree of adiposity, suggesting that the accuracy of BIA is negatively affected by obesity.