Psychosocial and Behavioral Aspects of Bariatric Surgery

Bariatric surgery has become an increasingly popular treatment option for individuals with extreme obesity (defined as a BMI ≥ 40 kg/m²) or those with less severe obesity accompanied by significant comorbidities. Sustained postoperative weight loss and improvements in obesity‐related health problems make bariatric surgery the most effective treatment for this population. Nevertheless, most experts agree that psychosocial and behavioral factors contribute to successful postoperative outcomes. This paper reviews the literature on the preoperative psychosocial status, eating behaviors, and quality of life of patients who seek bariatric surgery. In addition, the paper examines studies that investigated changes in these factors postoperatively. The review concludes with an agenda for future research in this area.     

Improved Arteriole‐to‐Venule Ratio of Retinal Vessels Resulting From Bariatric Surgery

Obesity causes increased morbidity and mortality from metabolic and cardiovascular disease (CVD). We investigated the effect of bariatric surgery on endothelial dysfunction (ED) in retinal vessels as a marker of metabolic and cardiovascular risk in patients with obesity WHO III. Thirty consecutive patients (19/11, w/m) were evaluated by anthropometry, lipid profile, and oral glucose tolerance test before and after bariatric surgery (Mannheim Obesity Study (MOS); NCT 00770276). Risk stratification was performed by the presence of metabolic syndrome (MetS) according to ATP‐III (adult treatment panel‐III). Subclinical atherosclerosis was assessed by measurement of intima‐media thickness (IMT). Flicker light response of retinal vessels was used as measures of ED. We measured their arteriole‐to‐venule ratio (AVR) for evaluation of vascular pathology. After a median of 9 months following bariatric surgery, mean weight loss was 39.4 kg (37.3%). Remission of impaired glucose metabolism was achieved in 53.3% of affected patients. Dyslipidemia improved significantly (triglycerides ?61.3 mg/dl, P < 0.0001, total cholesterol ?28.2 mg/dl, P = 0.002, and low‐density lipoprotein cholesterol were reduced ?24.5 mg/dl, P = 0.008). This resulted in a significant reduction of patients classified for MetS (27 vs. 9, P < 0.0001). Adiponectin increased by 2.08 µg/l (P = 0.032) and high sensitivity C‐reactive protein (hs‐CRP) and soluble intercellular cell adhesion molecule (sICAM) decreased (?7.3 mg/l, P < 0.0001 and ?146.4 ng/ml, P = 0.0006). AVR improved significantly (+0.04, P < 0.0001), but neither Flicker light response nor IMT changed significantly. Retinal AVR is ameliorated after bariatric intervention. As an increased AVR results from either or both widening retinal arteriolar caliber and narrowing retinal venular caliber, an improvement in small vessel profile is evident 9 months after bariatric surgery.     

Reconsidering connectivity in the sub‐Antarctic

Extreme and remote environments provide useful settings to test ideas about the ecological and evolutionary drivers of biological diversity. In the sub‐Antarctic, isolation by geographic, geological and glaciological processes has long been thought to underpin patterns in the region's terrestrial and marine diversity. Molecular studies using increasingly high‐resolution data are, however, challenging this perspective, demonstrating that many taxa disperse among distant sub‐Antarctic landmasses. Here, we reconsider connectivity in the sub‐Antarctic region, identifying which taxa are relatively isolated, which are well connected, and the scales across which this connectivity occurs in both terrestrial and marine systems. Although many organisms show evidence of occasional long‐distance, trans‐oceanic dispersal, these events are often insufficient to maintain gene flow across the region. Species that do show evidence of connectivity across large distances include both active dispersers and more sedentary species. Overall, connectivity patterns in the sub‐Antarctic at intra‐ and inter‐island scales are highly complex, influenced by life‐history traits and local dynamics such as relative dispersal capacity and propagule pressure, natal philopatry, feeding associations, the extent of human exploitation, past climate cycles, contemporary climate, and physical barriers to movement. An increasing use of molecular data – particularly genomic data sets that can reveal fine‐scale patterns – and more effective international collaboration and communication that facilitates integration of data from across the sub‐Antarctic, are providing fresh insights into the processes driving patterns of diversity in the region. These insights offer a platform for assessing the ways in which changing dispersal mechanisms, such as through increasing human activity and changes to wind and ocean circulation, may alter sub‐Antarctic biodiversity patterns in the future.     

Bariatric Surgery Patients’ Views of Their Physicians’ Weight‐Related Attitudes and Practices

Objective: A prior study found that nearly 80% of bariatric surgery patients felt that they were treated disrespectfully by members of the medical profession. This study assessed patient‐physician interactions in a group of bariatric surgery patients and in a group of less obese patients who sought weight loss by other means. Research Methods and Procedures: A total of 105 bariatric surgery candidates (mean BMI, 54.8 kg/m²) and 214 applicants to a randomized controlled trial of the effects of behavior modification and sibutramine (mean BMI, 37.8 kg/m²) completed a questionnaire that assessed patient‐physician interactions concerning weight. Results: Only 13% of bariatric surgery patients reported that they were usually or always treated disrespectfully by members of the medical profession, a percentage substantially lower than that found in the previous study. Surprisingly, surgery patients were significantly more satisfied than nonsurgery patients with the care they received for their obesity. Surgery patients also reported significantly more interactions with physicians concerning obesity and weight loss compared with nonsurgery patients. A substantial percentage of both groups, however, reported that their physician did not discuss weight control with them. Discussion: These and other findings suggest that doctor‐patient interactions concerning weight may have improved in the past decade; however, there is still much room for improvement. Increased efforts are needed to help physicians discuss, assess, and potentially treat obesity in primary care practice.     

Pre‐ to Postoperative Physical Activity Changes in Bariatric Surgery Patients: Self Report vs. Objective Measures

Bariatric surgery patients report significant pre‐ to postoperative increases in physical activity (PA). However, it is unclear whether objective measures would corroborate these changes. The present study compared self‐reported and accelerometer‐based estimates of changes in moderate‐to‐vigorous intensity PA (MVPA) from pre‐ (pre‐op) to 6 months postsurgery (post‐op). Twenty bariatric surgery (65% laparoscopic‐adjustable gastric banding, 35% gastric bypass) patients (46.2 ± 9.8 years, 88% female, pre‐op BMI = 50.8 ± 9.7 kg/m²) wore RT3 accelerometers as an objective measure of MVPA and completed the Paffenbarger Physical Activity Questionnaire (PPAQ) as a subjective measure before and 6 months after bariatric surgery. Time (min/week) spent in MVPA was calculated for the PPAQ and RT3 (≥1‐min and ≥10‐min bouts) at pre‐op and post‐op. Self‐reported MVPA increased fivefold from pre‐op to post‐op (44.6 ± 80.8 to 212.3 ± 212.4 min/week; P < 0.005). By contrast, the RT3 showed nonsignificant decreases in MVPA for both ≥1‐min (186.0 ± 169.0 to 151.2 ± 118.3 min/week) and ≥10‐min (41.3 ± 109.3 to 39.8 ± 71.3 min/week) bouts. At pre‐op, the percentage of participants who accumulated ≥150‐min/week of MVPA in bouts ≥10‐min according to the PPAQ and RT3 was identical (10%). However, at post‐op, 55% of participants reported compliance with the recommendation compared to 5% based on RT3 measurement (P = 0.002). Objectively‐measured changes in MVPA from pre‐op to 6 months post‐op appear to be much smaller than self‐reported changes. Further research involving larger samples is needed to confirm these findings and to determine whether self‐report and objective PA measures are differentially associated with surgical weight loss outcomes.     

Low 25‐Hydroxyvitamin D Does Not Affect Insulin Sensitivity in Obesity after Bariatric Surgery

Objective: A positive correlation between levels of 25‐hydroxyvitamin D [25(OH)D] and insulin sensitivity has been shown in healthy subjects. We aimed to test the hypothesis that concentration of 25(OH)D influences insulin sensitivity in obesity before and after weight loss. Research Methods and Procedures: We investigated the relation between serum 25(OH)D and insulin sensitivity (estimated by euglycemic‐hyperinsulinemic clamp) in 116 obese women (BMI ≥ 40 kg/m²) evaluated before and 5 and 10 years after biliopancreatic diversion (BPD). Body composition was estimated by the isotope dilution method. Results: Prevalence of hypovitaminosis D was 76% in the obese status and 91% and 89% at 5 and 10 years after BPD, respectively, despite ergocalciferol supplementation. 25(OH)D concentration decreased from 39.2 ± 22.3 in obesity (p = 0.0001) to 27.4 ± 16.4 and 25.1 ± 13.9 nM 5 and 10 years after BPD, respectively. Whole‐body glucose uptake increased from 24.27 ± 4.44 at the baseline to 57.29 ± 11.56 and 57.71 ± 8.41 μmol/kg_{fat free mass} per minute 5 and 10 years after BPD, respectively (p = 0.0001). Predictor of 25(OH)D was fat mass (R² = 0.26, p = 0.0001 in obesity; R² = 0.20, p = 0.02 after BPD). Parathormone correlated with fat mass (R² = 0.19; p = 0.0001) and BMI (R² = 0.053; p = 0.01) and inversely with M value (R² = 0.16; p = 0.0001), but only in obese subjects. Discussion: A high prevalence of hypovitaminosis D was observed in morbid obesity both before and after BPD. Low 25(OH)D did not necessarily imply increased insulin resistance after BPD, a condition where, probably, more powerful determinants of insulin sensitivity overcome the low circulating 25(OH)D levels. However, the present data cannot exclude some kind of influence of vitamin D status on glucose and insulin metabolism.     

Appropriateness Criteria for Bariatric Surgery: Beyond the NIH Guidelines

Careful selection of bariatric patients is critical for successful outcomes. In 1991, the NIH first established patient selection guidelines; however, some surgeons operate on individuals outside of these criteria, i.e., extreme age groups. We developed appropriateness criteria for the spectrum of patient characteristics including age, BMI, and severity of eight obesity‐related comorbidities. Candidate criteria were developed using combinations of patient characteristics including BMI: ≥40 kg/m², 35–39, 32–34, 30–31, <30; age: 12–18, 19–55, 56–64, 65+ years old; and comorbidities: prediabetes, diabetes, hypertension, dyslipidemia, sleep apnea, venous stasis disease, chronic joint pain, and gastroesophageal reflux (plus severity level). Criteria were formally validated on their appropriateness of whether the benefits of surgery clearly outweighed the risks, by an expert panel using the RAND/UCLA modified Delphi method. Nearly all comorbidity severity criteria for patients with BMI ≥40 kg/m² or BMI = 35–39 kg/m² in intermediate age groups were found to be appropriate for surgery. In contrast, patients in the extreme age categories were considered appropriate surgical candidates under fewer conditions, primarily the more severe comorbidities, such as diabetes and hypertension. For patients with a BMI of 32–34, only the most severe category of diabetes (Hgb A1c >9, on maximal medical therapy), is an appropriate criterion for those aged 19–64, whereas many mild to moderate severity comorbidity categories are “inappropriate.” There is overwhelming agreement among the panelists that the current evidence does not support performing bariatric surgery in lower BMI individuals (BMI <32). This is the first development of appropriateness criteria for bariatric surgery that includes severity categories of comorbidities. Only for the most severe degrees of comorbidities were adolescent and elderly patients deemed appropriate for surgery. Patient selection for bariatric procedures should include consideration of both patient age and comorbidity severity.     

Bariatric Surgery and the Role of the Clinical Endocrinologist: 2011 Update

ObjectiveTo discuss the emerging roles of bariatric surgery and clinical endocrinology within the context of obesity and diabetes mellitus comprehensive care plans and cost-effective strategies.MethodsRelevant literature is reviewed and clinical cases are presented.ResultsThe global obesity epidemic poses many challenges to clinical endocrinologists and has fomented a coordinated effort among specialists to revolutionize management paradigms. Technologic innovation drives the need for accelerated learning and research efforts in bariatric surgery. The national shortage of physicians with expertise in nutritional medicine compounds the management problems for this expanding patient population. Certain issues merit continued attention and research, such as gastric banding for mild obesity, surgery for treatment of diabetes, sleeve gastrectomy, and nutritional and metabolic consequences.ConclusionClinical endocrinologists should have a central role in the perioperative decision-making for patients undergoing bariatric surgery. (Endocr Pract. 2011;17:788-797)