Michael Devlin

Binge eating disorder: A multisite field trial of the diagnostic criteria

Diagnostic criteria have been developed for a new eating disorder, binge eating disorder (BED), to describe the many individuals who have problems with recurrent binge eating but do not engage in the characteristic compensatory behaviors of bulimia nervosa, vomiting, or use of laxatives. The results of a multisite field trial involving 1,984 subjects indicate that the disorder is common (30.1%) among subjects attending hospital-affiliated weight control programs, but is relatively rare in the community (2.0%). The disorder is more common in females than in males and is associated with severity of obesity and a history of marked weight fluctuations. Based on these results, the DSM-IV Work Group on Eating Disorders has recommended that the disorder be considered for inclusion in DSM-IV, either as an official category or in an appendix of categories requiring further study.

Body mass index and neurocognitive functioning across the adult lifespan.

OBJECTIVEnCognitive dysfunction and structural brain abnormalities have been observed in obese versus lean individuals, but with variability across age and weight groups. The current study was designed to clarify the cognitive profile of obesity by examining performance across multiple cognitive domains in adults with wide-ranging age and weight status.nnnMETHODnParticipants (N = 732; 61% women; ages 18-88; BMI range 19-75) underwent assessment of cognitive functioning and relevant medical/demographic covariates. Neuropsychological tests were grouped by cognitive domain (via confirmatory factor analysis), and standardized scores were averaged into composite variables.nnnRESULTSnHierarchical linear regression analyses revealed main effects for BMI on motor (ΔR2 = .02, β = -.15) and attention/processing speed (ΔR2 = .01, β = -.07), whereas a significant interaction between BMI and age was observed (ΔR2 = .01, β = -.08) for predicting executive functioning (p < .05). BMI was not independently associated with memory or language functioning and no interaction effects were observed for these variables. Although BMI was not independently related to executive dysfunction, a significant age × BMI interaction suggests that obesity-related executive deficits may increase with age.nnnCONCLUSIONSnOverall, these findings may support an independent association between obesity and a frontal-subcortical pathology, though prospective studies are needed to further clarify this possibility.

Cognitive function predicts 24-month weight loss success after bariatric surgery

BACKGROUNDnClinically significant cognitive impairment, particularly in attention/executive and memory function, is found in many patients undergoing bariatric surgery. These difficulties have previously been linked to decreased weight loss 12 months after surgery, but more protracted examination of this relationship has not yet been conducted. The present study prospectively examined the independent contribution of cognitive function to weight loss 24 months after bariatric surgery. Given the rapid rate of cognitive improvement observed after surgery, postoperative cognitive function (i.e., cognition 12 weeks after surgery, controlling for baseline cognition) was expected to predict lower body mass index (BMI) and higher percent total weight loss (%WL) at 24-month follow-up.nnnMETHODSnData were collected by 3 sites of the Longitudinal Assessment of Bariatric Surgery (LABS) parent project. Fifty-seven individuals enrolled in the LABS project who were undergoing bariatric surgery completed cognitive evaluation at baseline, 12 weeks, and 24 months. BMI and %WL were calculated for 24-month postoperative follow-up.nnnRESULTSnBetter cognitive function 12 weeks after surgery predicted higher %WL and lower BMI at 24 months, and specific domains of attention/executive and memory function were robustly related to decreased BMI and greater %WL at 24 months.nnnCONCLUSIONSnResults show that cognitive performance shortly after bariatric surgery predicts greater long-term %WL and lower BMI 24 months after bariatric surgery. Further work is needed to clarify the degree to which this relationship is mediated by adherence to postoperative guidelines.

The Role of Cognitive Function in Postoperative Weight Loss Outcomes: 36-Month Follow-Up

BackgroundCognitive dysfunction is associated with reduced postoperative weight loss up to 2xa0years following surgery, though the role of cognition at more extended follow-up is not yet understood. Thirty-six months following bariatric surgery, we retrospectively compared obese and non-obese patients on 12-week postoperative cognitive performance. We hypothesized that early postoperative cognitive dysfunction would predict higher body mass index (BMI) and lower percent weight loss (%WL) in the total sample at 36xa0month follow-up.Materials and MethodsFifty-five individuals undergoing bariatric surgery completed cognitive testing at preoperative baseline and serial postoperative timepoints, including 12xa0weeks and 36xa0months. Cognitive test scores were normed for demographic variables. Percent weight loss (%WL) and body mass index (BMI) were calculated at 36-month follow-up.ResultsAdjusting for gender, baseline cognitive function, and 12-week %WL, 12-week global cognitive test performance predicted 36xa0month postoperative %WL and BMI. Partial correlations revealed recognition memory, working memory, and generativity were most strongly related to weight loss.ConclusionCognitive function shortly after bariatric surgery is closely linked to extended postoperative weight loss at 36xa0months. Further work is necessary to clarify mechanisms underlying the relationship between weight loss, durability, and cognitive function, including contribution of adherence, as this may ultimately help identify individuals in need of tailored interventions to optimize postoperative weight loss.

Establishing guidelines for pharmacotherapy trials in bulimia nervosa and anorexia nervosa

OBJECTIVEnThis paper addresses the lack of a standard protocol for pharmacotherapy trials for patients with bulimia nervosa (BN) and anorexia nervosa (AN).nnnMETHODnTwenty-two surveys were sent to established researchers in the field of eating disorders to elicit their opinions regarding medication trials, including baseline laboratory tests, the optimal length/frequency of medication management sessions, and the information that should or should not be included in these sessions.nnnRESULTSnSixteen of 22 researchers completed and returned the survey. Their answers are the basis of the data presented.nnnDISCUSSIONnWe propose a battery of screening laboratory tests for both conditions. We suggest 30-45-min initial medication management sessions in both AN and BN trials with 15-min follow-ups to be held weekly for AN subjects, and weekly for 2 weeks, then biweekly for 2 weeks, then monthly, for BN subjects. We also recommend that published trials should include explicit details of medication management.

The Association Between Reduced Inflammation and Cognitive Gains After Bariatric Surgery.

Objective Bariatric surgery is associated with improved cognitive function, although the mechanisms are unclear. Elevated inflammation is common in obesity and associated with impaired cognition. Inflammation decreases after bariatric surgery, implicating it as a possible mechanism for cognitive improvement. The objective of this study was to examine whether reduced inflammation is a possible mechanism for postoperative cognitive improvement in bariatric surgery patients. Methods Participants were 77 bariatric surgery patients who completed cognitive testing before surgery and 1 year postsurgery. Cognitive domains assessed were attention/executive function, language, and memory. High-sensitivity C-reactive protein (CRP) was assessed at both time points. Results Patients exhibited preoperative cognitive impairment, although improvements 1 year postsurgery were seen in both attention/executive function (mean [M; standard deviation {SD}]baseline = 53.57 [8.68] versus M (SD)follow-up= 60.32 [8.19]) and memory (M [SD]baseline= 44.96 [7.98] versus M [SD]follow-up= 51.55 [8.25]). CRP was elevated at baseline and fell into the normative range postsurgery (M [SD]baseline= 0.9 [0.7] versus M [SD]follow-up= 0.2 [0.3] mg/dl). Preoperative CRP was not associated with baseline cognitive function (&bgr; values = −0.10 to 0.02) and changes in CRP also did not correspond to changes in cognition postsurgery (&bgr; values = 0.02–0.11; p values > .05 for all domains). A trend was detected for smaller improvements in memory among participants with elevated baseline CRP (>0.30 mg/dl) versus those with normal levels (group × time: p = .083). Conclusions Improvements in high-sensitivity CRP were not associated with postoperative cognitive benefits. Future studies are needed to explore other inflammatory markers and potential mechanisms of cognitive improvement after bariatric surgery, including improved glycemic control and neurohormone changes.

Mild cognitive impairment is prevalent in persons with severe obesity.

This study examines the prevalence of mild cognitive impairment (MCI) in a sample of adults with severe obesity and whether undergoing bariatric surgery reduces the frequency of MCI.

The Mini-Mental State Exam (MMSE) is not sensitive to cognitive impairment in bariatric surgery candidates

BACKGROUNDnCognitive dysfunction is common among bariatric surgery candidates and associated with poorer weight loss outcomes. Identification of a brief screening measure to detect cognitive impairment in this population is needed, because comprehensive neuropsychological evaluations may not be available in all clinical settings.nnnMETHODSnThe present study examined the utility of the Mini-Mental State Examination (MMSE) for detecting cognitive impairment in 30 bariatric surgery candidates by comparing impairment on the MMSE (at varying cutoffs) to impairment on a comprehensive neuropsychological test battery.nnnRESULTSnResults indicated that the MMSE showed low sensitivity and specificity in identifying impairment, even at the more stringent MMSE cutoffs of 27 and 28.nnnCONCLUSIONnThese findings suggest that the MMSE is a poor screener for cognitive impairment in bariatric surgery candidates. Future research is needed to identify or develop cognitive screeners for use in this population.

Implementation of a Weight Loss Program for Latino Outpatients with Severe Mental Illness

To determine feasibility of implementation of a weight loss program for overweight Latinos with severe mental illness. In this quasi-experimental study, a 14-week behavioral weight loss course (extended) was implemented at one clinic. A one-time nutrition class (brief) was given at a sister clinic. Implementation feasibility was assessed by consent and participation rates. Weight was followed for 6xa0months. Consent rates were high [77 % (49/64) extended; 68 % (39/57) brief], and 88 % (43/49) of extended subjects participated and 88 % (38/43) completed follow-up. Weight loss did not differ between groups. A behavioral weight loss course is feasible to implement for this population.

Adolescent weight history and adult cognition: before and after bariatric surgery.

BACKGROUNDnCognitive deficits occur in a subset of individuals with obesity. Deficits can be reversed with bariatric surgery, though cognitive recovery is not equally exhibited across patients. Recent work has found that obesity during adolescence portends medical complications in adulthood; it is unknown if obesity in adolescence predicts adult cognition or cognitive recovery after weight loss surgery.nnnOBJECTIVESnThe present study examines the relationship between weight history and cognitive function in obese adults undergoing bariatric surgery.nnnSETTINGnAcademic medical centers with bariatric care services.nnnMETHODSnSeventy-eight bariatric surgery patients (mean age = 43.2 years) enrolled in an ancillary study to the Longitudinal Assessment of Bariatric Surgery (LABS) project completed a questionnaire recalling weight history at age 18. Cognitive testing was completed preoperatively and at 12-month follow-up.nnnRESULTSnWeight status at age 18 was linked to performance in several aspects of cognition. Higher body mass index at age 18 predicted poorer preoperative verbal fluency (B = -.26, P = .045) as well as postoperative cognitive recovery in attention (B = -.30, P = .01) at 12-month follow-up.nnnCONCLUSIONnHigher body mass index at age 18 predicts verbal fluency performance in adults with obesity, as well as postoperative recovery of attention after bariatric surgery. The mechanisms underlying this connection are not fully clear, though findings may reflect effects of obesity on the brain during a crucial period of neural maturation or duration of obesity and cumulative impact of co-morbidities on cognition. Future work examining possible causal factors involved in these relationships is needed.