Prediction of response to sibutramine therapy in obese non-diabetic and diabetic patients

Unraveling the Variability of Human Satiation: Implications for Precision Obesity Management

Satiation is the physiologic process that regulates meal size and termination, and it is quantified by the calories consumed to reach satiation. Given its role in energy intake, changes in satiation contribute to obesity's pathogenesis. Our study employed a protocolized approach to study the components of food intake regulation including a standardized breakfast, a gastric emptying study, appetite sensation testing, and a satiation measurement by an ad libitummeal test. These studies revealed that satiation is highly variable among individuals, and while baseline characteristics, anthropometrics, body composition and hormones, contribute to this variability, these factors do not fully account for it. To address this gap, we explored the role of a germline polygenic risk score, which demonstrated a robust association with satiation. Furthermore, we developed a machine-learning-assisted gene risk score to predict satiation and leveraged this prediction to anticipate responses to anti-obesity medications. Our findings underscore the significance of satiation, its inherent variability, and the potential of a genetic risk score to forecast it, ultimately allowing us to predict responses to different anti-obesity interventions.

Evaluation and Treatment of Obesity and Its Comorbidities: 2022 Update of Clinical Practice Guidelines for Obesity by the Korean Society for the Study of Obesity

The goal of the 8th edition of the Clinical Practice Guidelines for Obesity is to help primary care physician provide safe, effective care to patients with obesity by offering evidence-based recommendations to improve the quality of treatment. The Committee for Clinical Practice Guidelines comprised individuals with multidisciplinary expertise in obesity management. A steering board of seven experts oversaw the entire project. Recommendations were developed as the answers to key questions formulated in patient/problem, intervention, comparison, outcomes (PICO) format. Guidelines underwent multi-level review and cross-checking and received endorsement from relevant scientific societies. This edition of the guidelines includes criteria for diagnosing obesity, abdominal obesity, and metabolic syndrome; evaluation of obesity and its complications; weight loss goals; and treatment options such as diet, exercise, behavioral therapy, pharmacotherapy, and bariatric and metabolic surgery for Korean people with obesity. Compared to the previous edition of the guidelines, the current edition includes five new topics to keep up with the constantly evolving field of obesity: diagnosis of obesity, obesity in women, obesity in patients with mental illness, weight maintenance after weight loss, and the use of information and communication technology-based interventions for obesity treatment. This edition of the guidelines features has improved organization, more clearly linking key questions in PICO format to recommendations and key references. We are confident that these new Clinical Practice Guidelines for Obesity will be a valuable resource for all healthcare professionals as they describe the most current and evidence-based treatment options for obesity in a well-organized format.

The Potential of Semaglutide Once-Weekly in Patients Without Type 2 Diabetes with Weight Regain or Insufficient Weight Loss After Bariatric Surgery-a Retrospective Analysis

Purpose

About 20–25% of patients experience weight regain (WR) or insufficient weight loss (IWL) after bariatric metabolic surgery (BS). Therefore, we aimed to retrospectively assess the effectiveness of adjunct treatment with the GLP-1 receptor agonist semaglutide in non-diabetic patients with WR or IWL after BS.

Materials and Methods

Post-bariatric patients without type 2 diabetes (T2D) with WR or IWL (n = 44) were included in the analysis. The primary endpoint was weight loss 3 and 6 months after initiation of adjunct treatment. Secondary endpoints included change in BMI, HbA1c, lipid profile, hs-CRP, and liver enzymes.

Results

Patients started semaglutide 64.7 ± 47.6 months (mean ± SD) after BS. At initiation of semaglutide, WR after post-bariatric weight nadir was 12.3 ± 14.4% (mean ± SD). Total weight loss during semaglutide treatment was − 6.0 ± 4.3% (mean ± SD, p < 0.001) after 3 months (3.2 months, IQR 3.0–3.5, n = 38) and − 10.3 ± 5.5% (mean ± SD, p < 0.001) after 6 months (5.8 months, IQR 5.8–6.4, n = 20). At 3 months, categorical weight loss was > 5% in 61% of patients, > 10% in 16% of patients, and > 15% in 2% of patients. Triglycerides (OR = 0.99; p < 0.05), ALT (OR = 0.87; p = 0.05), and AST (OR = 0.89; p < 0.05) at baseline were negatively associated with weight loss of at least 5% at 3 months’ follow-up (p < 0.05).

Conclusion

Treatment options to manage post-bariatric excess weight (regain) are scarce. Our results imply a clear benefit of adjunct treatment with semaglutide in post-bariatric patients. However, these results need to be confirmed in a prospective randomized controlled trial to close the gap between lifestyle intervention and revision surgery in patients with IWL or WR after BS.

Graphical abstract

Future directions in obesity pharmacotherapy

There is a growing unmet need for more effective treatment of obesity and its complications. While current anti-obesity medications are effective and offer real clinical benefits over diet and lifestyle interventions, they cannot meet the levels of efficacy and reduction of hard endpoint outcomes seen with bariatric surgery. As knowledge on the control of body weight unravels, the complexity of this physiology opens the opportunity to new druggable targets. Currently, gut peptide analogues such as semaglutide, a glucagon like peptide-1 (GLP-1) receptor agonist, and the dual agonist GLP-1 and gastric inhibitory polypeptide (GIP) tirzepatide are the furthest advanced in clinical development and seem likely to meet current regulatory requirements within the next year or so. However, current regulatory requirements are out of step with the efficacy of new compounds and concepts relating to obesity and its complications. Many other drugs in early development will target different pathways of energy balance, raising the possibility of drug combinations to maximise efficacy as for other chronic disease such as hypertension and diabetes. This will allow more complex and personalised guidelines to evolve.

ONE MONTH WEIGHT LOSS PREDICTS THE EFFICACY OF LIRAGLUTIDE IN OBESE PATIENTS: DATA FROM A SINGLE CENTER

Objective: Liraglutide is a glucagon-like peptide 1 receptor agonist which acts through peripheral and central receptor pathways affecting food intake. Preliminary identification of responder patients represents a crucial point to reduce an inappropriate exposure to the drug and the health expenditure. The primary endpoint of our study was to identify predictors of liraglutide efficacy in the short term follow-up. The secondary endpoint was to evaluate the treatment efficacy stratified by the underlying psychiatric disorder. Methods: We evaluated a cohort of 100 patients (77 females, 23 males, mean body mass index 38.6 ± 3.2 kg/m²) who were evaluated at baseline, and after 1, 3, and 6 months of treatment. Liraglutide efficacy was defined by a weight loss ≥5% of initial weight. Sociodemographic/metabolic parameters, food intake, smoking habit, and physical activity were correlated with liraglutide efficacy. Results: There was a significant weight loss after 1 month of therapy, as well as after 3 and 6 months when compared to the baseline (P<.0001; 27%, 45%, and 57% of patients showed a weight loss ≥5%, respectively). No difference was found in weight loss between the 3 groups of patients (with binge eating, with/without psychiatric disorders). The weight loss at 1 month was the only predictor of a positive response to the treatment. Conclusion: Our results confirm the efficacy of liraglutide even at a lower dose than conventional. The early response to the drug seems to be a good predictor of long-term efficacy and it might be useful in clinical practice to identify patients in whom liraglutide may induce a significant weight loss. Abbreviations: BMI = body mass index; EMA = European Medicine Agency; FDA = Food and Drug Administration; GLP-1 RA = glucagon-like peptide 1 receptor agonist.

[Conjugated linoleic acid improves glucose and lipid metabolism in diabetic mice]

OBJECTIVE

To analyze the effect of conjugated linoleic acid (CLA) on glucose and lipid metabolism in obese diabetic (db/db) mice.

METHODS

db/db mice were randomized for treatment with saline or CLA mixture administered intragastrically. The changes in body weight, dietary intake, water intake, oral glucose tolerance, triglyceride and total cholesterol were recorded after the treatments. HE staining and oil red O staining were used to assess liver pathologies and fatty acid content. The expression levels of PPARα, PPARγ, CD36, CHREBP and SREBP-1c were detected using real-time PCR and Western blotting. HepG2 cells were treated with CLA and linoleic acid and the expressions of PPARα, ACC, P-ACC, and CD36 were detected; the level of acetyl-CoA in the cell supernatant was detected using ELISA.

RESULTS

CLA treatment obviously reduced the dietary and water intake of db/db mice, effectively reduced the body weight and decreased serum triglyceride and cholesterol levels (P &lt; 0.05). CLA significantly reduced fasting blood glucose, increased glucose tolerance, reduced the accumulation of lipid droplets in the liver and improved lipid metabolism in db/db mice. The mice showed significantly increased expression of PPARα (P &lt; 0.05) and lowered CD36 expression (P &lt; 0.001) in the liver after CLA treatment. Cellular experiments showed that CLA significantly up-regulated PPARα (P &lt; 0.001) and P-ACC and decreased the expression of CD36 (P &lt; 0.01). ELISA showed that acetyl-CoA was significantly up-regulated in the cells after CLA treatment (P &lt; 0.01).

CONCLUSIONS

The mixture of two conjugated linoleic acid isomers can reduce fasting blood glucose, increase glucose tolerance and improve glycolipid metabolism in db/db mice by enhancing the expression of PPARα, increasing P-ACC and inhibiting CD36 expression.

Precision Medicine in Weight Loss and Healthy Living

Obesity affects 600 million people globally and over one third of the American population. Along with associated comorbidities, including cardiovascular disease, stroke, diabetes, and cancer; the direct and indirect costs of managing obesity are 21% of the total medical costs. These factors shed light on why developing effective and pragmatic strategies to reduce body weight in obese individuals is a major public health concern. An estimated 60-70% of obese Americans attempt to lose weight each year, with only a small minority able to achieve and maintain long term weight loss. To address this issue a precision medicine approach for weight loss has been considered, which places an emphasis on sustainability and real-world application to individualized therapy. In this article we review weight loss interventions in the context of precision medicine and discuss the role of genetic and epigenetic factors, pharmacological interventions, lifestyle interventions, and bariatric surgery on weight loss.

Effect of a high-egg diet on cardiometabolic risk factors in people with type 2 diabetes: the Diabetes and Egg (DIABEGG) Study-randomized weight-loss and follow-up phase

Background

Some country guidelines recommend that people with type 2 diabetes (T2D) limit their consumption of eggs and cholesterol. Our previously published 3-mo weight-maintenance study showed that a high-egg (≥12 eggs/wk) diet compared with a low-egg diet (<2 eggs/wk) did not have adverse effects on cardiometabolic risk factors in adults with T2D.

Objective

The current study follows the previously published 3-mo weight-maintenance study and assessed the effects of the high-egg compared with the low-egg diets as part of a 3-mo weight-loss period, followed by a 6-mo follow-up period for a total duration of 12 mo.

Design

Participants with prediabetes or T2D (n = 128) were prescribed a 3-mo daily energy restriction of 2.1 MJ and a macronutrient-matched diet and instructed on specific types and quantities of foods to be consumed, with an emphasis on replacing saturated fats with monounsaturated and polyunsaturated fats. Participants were followed up at the 9- and 12-mo visits.

Results

From 3 to 12 mo, the weight loss was similar (high-egg compared with low-egg diets: -3.1 ± 6.3 compared with -3.1 ± 5.2 kg; P = 0.48). There were no differences between groups in glycemia (plasma glucose, glycated hemoglobin, 1,5-anhydroglucitol), traditional serum lipids, markers of inflammation (high-sensitivity C-reactive protein, interleukin 6, soluble E-selectin), oxidative stress (F2-isoprostanes), or adiponectin from 3 to 12 mo or from 0 to 12 mo.

Conclusions

People with prediabetes or T2D who consumed a 3-mo high-egg weight-loss diet with a 6-mo follow-up exhibited no adverse changes in cardiometabolic markers compared with those who consumed a low-egg weight-loss diet. A healthy diet based on population guidelines and including more eggs than currently recommended by some countries may be safely consumed. This trial is registered at http://www.anzctr.org.au/ as ACTRN12612001266853.

Pharmacotherapy for Patients with Obesity

BACKGROUND

Although pharmacotherapy is not the cornerstone of obesity treatment, it is a valuable tool that could be considered for patients who have not had adequate benefit from lifestyle interventions or who have difficulty maintaining initial weight loss over longer periods.

CONTENT

This review focuses on the role of antiobesity drugs, the mechanisms by which the drugs work, potential pharmacological targets in the neural control of food intake and regulation of body weight, the history of antiobesity drugs, a summary of efficacy and safety data from clinical trials, and the clinical application of pharmacotherapy. Currently, 5 approved drug therapies are available in the US for long-term weight management, with only 2 of these meeting the stronger Food and Drug Administration (FDA) criteria of 5% weight loss relative to a placebo after 1 year and others receiving approval based on the categorical criterion of the proportions of patients achieving 5% weight loss. Interpretation of the results of clinical trials conducted before regulatory agency approval is limited by high dropout rates; thus, the results might not be replicable in clinical practice settings. Many patients who are suitable candidates for pharmacotherapy are not using the new drugs due to lack of insurance coverage and high out-of-pocket costs.

SUMMARY

With the availability of 4 new drugs since 2012, clinicians in the US now have more tools for long-term weight management. The quality of pharmacotherapy clinical investigations needs considerable improvement. Future research should focus on examining the mediators and moderators of response.

Effects of resistant dextrin for weight loss in overweight adults: a systematic review with a meta-analysis of randomized controlled trials

BACKGROUND

Randomized controlled trials (RCTs) reported that resistant dextrin (RD) exerted pleiotropic effects on humans. However, limited information is available on the effects of RD for weight loss. We conducted a systematic review with a meta-analysis to summarize the available literature and compare the efficacy of RD for weight loss with that of a placebo in overweight adults.

METHODS

We searched the electronic databases MEDLINE, EMBASE, The Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, Web of Science, ClincalTrials.gov, and Japana Centra Revuo Medicina (Ichushi-web) for studies from their onset to November 2016, and there was no language restriction. Trials were included if they were RCTs (1) comparing the effects of RD with a placebo in adults (18 years or older), (2) reporting body mass index, and (3) including overweight/obese subjects as defined by the authors of RCTs. The weighted mean difference with a 95% confidence interval (CI) was calculated using a random-effects model.

RESULTS

Of the 484 studies retrieved, 3 RCTs involving 275 subjects were included in our review. The durations of RCTs ranged between 8 and 12 weeks. All RCTs were conducted in Asian countries. RD significantly improved body mass index [mean difference -0.39 (95% CI -0.57 to -0.21) kg/m², p < 0.01] and body weight [mean difference -0.81 (95% CI -0.93 to -0.69) kg, p < 0.01] in overweight adults.

CONCLUSION

Our review suggests that RD exerts beneficial effects for weight loss in overweight adults. More RCTs with different populations and longer follow-ups are needed in order to confirm that supplementation with RD has beneficial effects for weight loss in overweight adults. We consider this review to provide important information for the future submission of food with health claims.

Early Weight Loss with Liraglutide 3.0 mg Predicts 1-Year Weight Loss and is Associated with Improvements in Clinical Markers

OBJECTIVE

To identify an early response criterion for predicting ≥5% weight loss with liraglutide 3.0 mg at week 56 and to compare efficacy outcomes in early responders (ERs) and early nonresponders (ENRs).

METHODS

Using pooled data from the SCALE Obesity and Prediabetes and SCALE Diabetes trials, weight loss of ≥4% at 16 weeks best predicted ≥5% weight loss after 56 weeks. Weight loss and changes in cardiometabolic risk factors and health-related quality of life were evaluated in ERs (≥4% weight loss at week 16) and ENRs (<4% weight loss at week 16) completing 56 weeks' treatment.

RESULTS

Proportions of ERs/ENRs to liraglutide 3.0 mg were 77.3%/22.7% (individuals without type 2 diabetes, T2D) and 62.7%/37.3% (those with T2D). Greater mean weight loss was observed in ERs versus ENRs: 10.8% versus 3.0% (without T2D) and 8.5% versus 3.1% (T2D). In both trials, greater proportions of ERs versus ENRs achieved ≥5%, >10%, and >15% weight loss at week 56 with liraglutide 3.0 mg. Greater improvements in cardiometabolic risk factors and health-related quality of life scores were observed in ERs versus ENRs.

CONCLUSIONS

The early response criterion was clinically useful to identify individuals who would achieve clinically meaningful weight loss at 56 weeks.

The relationship between early weight loss and weight loss at 1 year with naltrexone ER/bupropion ER combination therapy

BACKGROUND/OBJECTIVES

Weight management medications increase the likelihood that patients will achieve clinically meaningful improvements in cardiovascular, metabolic and other weight-related measures of health. However, the weight loss achieved with any weight management intervention can vary widely among individuals, and patients who do not respond to pharmacotherapy by achieving clinically meaningful weight loss should discontinue therapy. We characterized 1-year weight loss in the phase 3 clinical trial program of the weight management medication, naltrexone/bupropion 32/360 mg (NB), as well as the relationship between early weight loss and long-term weight loss, particularly with respect to participants who achieved the clinically recommended threshold of ⩾5% weight loss by Week 16.

PARTICIPANTS/METHODS

Data from participants from each of the four phase 3, randomized, placebo-controlled, 56-week clinical trials with NB were pooled (modified intent-to-treat population; NB N=2043, Placebo N=1319). This exploratory analysis examined the relationship between participant achievement of various weight loss thresholds early in treatment (at Week 8, 12 or 16) and the associated weight loss at Week 56 (Completers population; NB N=1310, Placebo N=763).

RESULTS

In the NB participants who completed 1 year of treatment, weight loss of at least 5% at Week 16 (n=873) was associated with least-squares mean weight loss of 11.7% at Week 56 and 85% of these participants had Week 56 weight loss of ⩾5%. Eighty percent (95% confidence interval: 78-82%) of the participants who would, and would not, achieve ⩾5% weight loss at Week 56 were correctly identified using the clinically recommended threshold of ⩾5% at Week 16. Safety and tolerability of NB was similar to previously published reports.

CONCLUSIONS

Participants who meet the Week 16 threshold of ⩾5% weight loss are likely to maintain clinically significant weight loss after 1 year of treatment. Further evaluations are required to evaluate improvements in measures of cardiovascular and metabolic risk.

Evolution of pharmacological obesity treatments: focus on adverse side-effect profiles

Pharmacotherapy directed toward reducing body weight may provide benefits for both curbing obesity and lowering the risk of obesity-associated comorbidities; however, many weight loss medications have been withdrawn from the market because of serious adverse effects. Examples include pulmonary hypertension (aminorex), cardiovascular toxicity, e.g. flenfluramine-induced valvopathy, stroke [phenylpropanolamine (PPA)], excess non-fatal cardiovascular events (sibutramine), and neuro-psychiatric issues (rimonabant; approved in Europe, but not in the USA). This negative experience has helped mould the current drug development and approval process for new anti-obesity drugs. Differences between the US Food and Drug Administration (FDA) and the European Medicines Agency, however, in perceptions of risk-benefit considerations for individual drugs have resulted in discrepancies in approval and/or withdrawal of weight-reducing medications. Thus, two drugs recently approved by the FDA, i.e. lorcaserin and phentermine + topiramate extended release, are not available in Europe. In contrast, naltrexone sustained release (SR)/bupropion SR received FDA approval, and liraglutide 3.0 mg was recently approved in both the USA and Europe. Regulatory strategies adopted by the FDA to manage the potential for uncommon but potentially serious post-marketing toxicity include: (i) risk evaluation and mitigation strategy programmes; (ii) stipulating post-marketing safety trials; (iii) considering responder rates and limiting cumulative exposure by discontinuation if weight loss is not attained within a reasonable timeframe; and (iv) requiring large cardiovascular outcome trials before or after approval. We chronicle the adverse effects of anti-obesity pharmacotherapy and consider how the history of high-profile toxicity issues has shaped the current regulatory landscape for new and future weight-reducing drugs.

Update on Prevention of Cardiovascular Disease in Adults With Type 2 Diabetes Mellitus in Light of Recent Evidence: A Scientific Statement From the American Heart Association and the American Diabetes Association

Cardiovascular disease risk factor control as primary prevention in patients with type 2 diabetes mellitus has changed substantially in the past few years. The purpose of this scientific statement is to review the current literature and key clinical trials pertaining to blood pressure and blood glucose control, cholesterol management, aspirin therapy, and lifestyle modification. We present a synthesis of the recent literature, new guidelines, and clinical targets, including screening for kidney and subclinical cardiovascular disease for the contemporary management of patients with type 2 diabetes mellitus.

Update on Prevention of Cardiovascular Disease in Adults With Type 2 Diabetes Mellitus in Light of Recent Evidence: A Scientific Statement From the American Heart Association and the American Diabetes Association

Cardiovascular disease risk factor control as primary prevention in patients with type 2 diabetes mellitus has changed substantially in the past few years. The purpose of this scientific statement is to review the current literature and key clinical trials pertaining to blood pressure and blood glucose control, cholesterol management, aspirin therapy, and lifestyle modification. We present a synthesis of the recent literature, new guidelines, and clinical targets, including screening for kidney and subclinical cardiovascular disease for the contemporary management of patients with type 2 diabetes mellitus.

Early weight loss while on lorcaserin, diet and exercise as a predictor of week 52 weight-loss outcomes

OBJECTIVE

To identify an early treatment milestone that optimizes sensitivity and specificity for predicting ≥5% weight loss at Week (W) 52 in patients with and without type 2 diabetes on lorcaserin or placebo.

METHODS

Post hoc area under the curve for receiver operating characteristic analyses of data from three phase 3 trials comparing lifestyle modification+placebo with lifestyle modification+lorcaserin. A total of 6897 patients (18-65 years; BMI, 30-45 or 27-29.9 kg/m(2) with ≥1 comorbidity) were randomized to placebo or lorcaserin 10 mg bid. Changes (baseline to W52) in cardiometabolic parameters were assessed.

RESULTS

Response (≥5% weight loss from baseline) at W12 was a strong predictor of W52 response. Lorcaserin patients with a W12 response achieved mean W52 weight losses of 10.6 kg (without diabetes) and 9.3 kg (with diabetes). Proportions achieving ≥5% and ≥10% weight loss at W52 were 85.5% and 49.8% (without diabetes), and 70.5% and 35.9% (with diabetes). Lorcaserin patients who did not achieve a W12 response lost 3.2 kg (without diabetes) and 2.8 kg (with diabetes) at W52. Responders had greater improvements in cardiometabolic risk factors than the modified intent-to-treat (MITT) population, consistent with greater weight loss.

CONCLUSIONS

≥5% weight loss by W12 predicts robust response to lorcaserin at 1 year.

The impact of a weight reduction program with and without meal-replacement on health related quality of life in middle-aged obese females

BACKGROUND

In addition to an increased risk for chronic illnesses, obese individuals suffer from social stigmatization and discrimination, and severely obese people may experience greater risk of impaired psychosocial and physical functioning. Lower health-related quality of life (HRQOL) has been reported among obese persons seeking intensive treatment for their disease. To aid in the treatment of obesity, meal replacements have been recommended as an effective therapeutic strategy for weight loss, particularly when consumed in the beginning of an intervention. Hence, the objective of this study was to assess the impact of two 12-month weight reduction interventions (one arm including a meal replacement) on changes in HRQOL among obese females.

METHODS

This controlled trial compared two versions of a standardized 12-month weight reduction intervention: the weight-reduction lifestyle program without a meal replacement (LS) versus the same lifestyle program with the addition of a soy-based meal replacement product (LSMR). 380 women (LS: n = 190, LSMR: n = 190) were matched by age, gender, and weight (51.4 ± 7.0 yrs., 35.5 ± 3.03 kg/m2). This sample of women all completed the 12-month lifestyle intervention that was part of a larger study. The lifestyle intervention included instruction on exercise/sport, psychology, nutrition, and medicine in 18 theoretical and 40 practical units. Led by a sport physiologist, participants engaged in group-based exercise sessions once or twice a week. To evaluate HRQOL, all participants completed the SF-36 questionnaire pre- and post-intervention. Anthropometric, clinical, physical performance (ergometric stress tests), and self-reported leisure time physical activity (hours/day) data were collected.

RESULTS

The LSMR sample showed lower baseline HRQOL scores compared to the LS sample in six of eight HRQOL dimensions, most significant in vitality and health perception (p < 0.01). After the intervention, body weight was reduced in both lifestyle intervention groups (LS: -6.6±6.6 vs. LSMR -7.6±7.9 kg), however, weight loss and HRQOL improvements were more pronounced in the LSMR sample (LSMR: seven of eight, LS: four of eight dimensions).

CONCLUSIONS

Our results show that HRQOL may improve among middle-aged obese females during a standardized lifestyle weight reduction program and may be enhanced by consuming a soy-based meal replacement product.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00356785.

Current pharmacotherapy for obesity: extrapolation of clinical trials data to practice

INTRODUCTION

When used prudently and in combination with lifestyle modification, pharmacotherapy has an important role in the management of obesity.

AREAS COVERED

This review covers targets for antiobesity drugs, challenges and limitations, failed translation of basic science to clinical practice, methodological and regulatory issues in clinical trials of pharmacotherapy, efficacy and risks of drugs currently approved for obesity, and clinical practice issues when using antiobesity drugs with emphasis on recently approved drugs.

EXPERT OPINION

Drugs currently approved for long-term therapy of obesity offer modest benefits for most patients, substantial benefits for some and no benefits for others. Numerous methodological problems including exclusion of the type of patients who are most often seen in clinical practices, inadequate enrollment of men and minorities, exclusion of patients taking antidepressants, high dropout rates, lack of follow-up after treatment discontinuation, and less than ideal imputation methods in data analysis limit the interpretation of clinical trials data and generalizability. Single-drug therapies offer small to moderate weight-loss benefits, but are generally better tolerated. Efficacy is enhanced with combination drug therapies, but so are the hazards. Clinicians should base their decisions on the expected and observed benefit-to-risk balance.

Long-term drug treatment for obesity: a systematic and clinical review

IMPORTANCE

Thirty-six percent of US adults are obese, and many cannot lose sufficient weight to improve health with lifestyle interventions alone.

OBJECTIVE

To conduct a systematic review of medications currently approved in the United States for obesity treatment in adults. We also discuss off-label use of medications studied for obesity and provide considerations for obesity medication use in clinical practice.

EVIDENCE REVIEW

A PubMed search from inception through September 2013 was performed to find meta-analyses, systematic reviews, and randomized, placebo-controlled trials for currently approved obesity medications lasting at least 1 year that had a primary or secondary outcome of body weight change, included at least 50 participants per group, reported at least 50% retention, and reported results on an intention-to-treat basis. Studies of medications approved for other purposes but tested for obesity treatment were also reviewed.

FINDINGS

Obesity medications approved for long-term use, when prescribed with lifestyle interventions, produce additional weight loss relative to placebo ranging from approximately 3% of initial weight for orlistat and lorcaserin to 9% for top-dose (15/92 mg) phentermine plus topiramate-extended release at 1 year. The proportion of patients achieving clinically meaningful (at least 5%) weight loss ranges from 37% to 47% for lorcaserin, 35% to 73% for orlistat, and 67% to 70% for top-dose phentermine plus topiramate-extended release. All 3 medications produce greater improvements in many cardiometabolic risk factors than placebo, but no obesity medication has been shown to reduce cardiovascular morbidity or mortality. Most prescriptions are for noradrenergic medications, despite their approval only for short-term use and limited data for their long-term safety and efficacy.

CONCLUSIONS AND RELEVANCE

Medications approved for long-term obesity treatment, when used as an adjunct to lifestyle intervention, lead to greater mean weight loss and an increased likelihood of achieving clinically meaningful 1-year weight loss relative to placebo. By discontinuing medication in patients who do not respond with weight loss of at least 5%, clinicians can decrease their patients' exposure to the risks and costs of drug treatment when there is little prospect of long-term benefit.

Treatment of the obese patient in primary care: targeting and meeting goals and expectations

Obesity is a serious disease associated with increased patient risk of several comorbidities, including type 2 diabetes mellitus, cardiovascular disease, dyslipidemia, hypertension, some cancers, and greater mortality. Furthermore, obesity has a deleterious impact on quality of life and increases health care costs. Moderate weight loss of 5% to 10% has been shown to significantly improve several patient cardiometabolic risk factors and physical functioning, however, it is often difficult to begin the weight-loss conversation with patients. Primary care providers play a critical role in discussing the health effects of excess weight with patients, managing obesity-related comorbidities, and recommending appropriate weight-loss strategies. Open communication, realistic goal setting, and consistent monitoring are key factors in implementing an effective weight-loss program in the primary care setting. Although diet and lifestyle modifications are the first lines of approach and the foundation of any weight-loss strategy, in many cases, additional interventions may be necessary, including medical or surgical management. Herein, we discuss the approaches that primary care providers should consider when recommending appropriate weight-loss strategies for overweight/obese patients to achieve clinically meaningful weight loss, including pharmacotherapies approved for chronic management of patients with obesity, to be used as adjuncts to diet and lifestyle modifications, and surgical options.

Why do we need drugs to treat the patient with obesity?

OBJECTIVE

Obesity is a public health problem, which increases the risk of chronic diseases and mortality. Weight loss can reduce mortality and improve most of the detrimental health consequences of obesity.

DESIGN AND METHODS

This paper was developed from two presentations to the US Food and Drug Administration (FDA), which has responsibility for reviewing and approving drugs to treat obesity.

RESULTS

A weight loss of 5% or more is sufficient to significantly reduce health risks in individuals with impaired glucose tolerance, hypertension, or nonalcoholic fatty liver disease. Slightly more weight loss (16% on average, achieved by surgery) reduces mortality. The goal of medicating for obesity is to help more patients achieve more weight loss. A barrier to drug approval has been the concern that weight loss medications might be used by individuals with little or no health risks, thus mandating a low side effect profile for approval of any drug. This limits the options for patients who have obesity-related health problems that could improve with weight loss. Recently the FDA signaled interest in identifying health benefits in higher risk patients that might justify medications with higher risk; however, the potential impact on a large segment of the population has led the FDA to consider requiring a cardiovascular outcome trial for all obesity medications, either prior to or after approval.

CONCLUSION

This review argues that drugs are needed for obesity because they enhance behaviorally induced weight loss and that new medications for obesity are needed in the approval process.

Predictors of Successful Weight Loss

The identification of variables in the early stages of treatment that are related to successful weight loss provides practitioners with important information. These factors may be assessed to determine the likelihood of future success. Weight loss at the beginning of treatment, depressive symptomatology, and social support, each of these has been shown to be predictive of long-term outcomes for weight loss efforts.

A study of the use of drugs in the treatment of obesity among adult females

Purpose

Obesity is a prevalent health problem among adult females in Egypt. The aim of this study is to investigate the use of drugs in managing of obesity among adult females.

Design/methodology/approach

A random sample of 764 obese adult females with a BMI >25 were included in the study. Data were collected using a pre‐coded questionnaire on personal characteristics, type of regimen followed, the use of anti‐obesity drugs, sources of information about medicine, compliance pattern and the outcome of using medicine.

Findings

The results show that 19.9 per cent of the females took medicines while dieting and another 11.4 per cent while dieting and exercising. Physicians were the main source of advice about anti‐obesity medicine (33.1 per cent), followed by pharmacists (25.5 per cent), peers (24.2 per cent) and mass media (17.2 per cent). Medicines stimulating the metabolism were most commonly used (42.7 per cent), followed by drugs blocking fat absorption (24.3 per cent), appetite depressants (23.3 per cent) and herbs (18.4 per cent). The most common side effects were diarrhoea (30.1 per cent) followed by headache (20.1 per cent) and depression (17.2 per cent). The data show that 47.7 per cent of the females fully complied while 30.5 per cent did not comply. The intake of medicine while dieting induced weight loss among 48.9 per cent of the subjects, 18.0 per cent did not report weight loss and 33.1 per cent stopped medicine intake. Older females and those with a BMI >35 were more keen to seek advice from a physician, were more likely to comply fully and reported the highest rate of weight loss. The use of anti‐obesity drugs was highest (44 per cent) among university graduates compared to 24.8 per cent among females with limited education.

Originality/value

This study presents the first report of the pattern of using anti‐obesity drugs in Egypt.

Clinical correlates of weight loss and attrition during a 10-week dietary intervention study: results from the NUGENOB project

OBJECTIVE

The aim of this study was to identify the pre-treatment subject characteristics and weight loss changes as determinants of weight loss and attrition during a 10-week dietary intervention study.

METHODS

A total of 771 obese subjects (BMI 35.6 kg/m(2)) of both genders were included from 8 clinical centres in 7 European countries, who underwent a 10-week dietary intervention study comparing two hypo-energetic (-600 kcal/day) diets varying in fat content.

RESULTS

The multiple regression model showed that weight loss at week 10 was predicted by: 6.55 + 1.27 × early weight loss (kg) at week 1 + 1.35 × gender (R(2) = 0.28, p < 0.001). When performing the corresponding model with half-way weight loss (week 5) as covariate, the regression equation was: weight loss (kg) at week 10 = 1.88 + 1.38 × half-way weight loss (kg) (week 5) + 0.42 × gender (R(2) = 0.77, p < 0.001). A cut-off target of ≥ 4 kg weight loss at week 5 emerged as an optimal predictor for reaching at least 10% weight loss at week 10. Greater attrition likelihood was predicted by high-fat diet, decreased early and half-way weight losses.

CONCLUSION

Early and half-way weight losses are associated with and could contribute to prediction of the final weight loss and attrition.

Efficacy and safety of CP-945,598, a selective cannabinoid CB1 receptor antagonist, on weight loss and maintenance

Three double-blind, placebo-controlled, three-parallel-group, multicenter phase 3 trials were conducted to assess the efficacy and safety of CP-945,598 for weight loss and weight-loss maintenance. Two trials were designed to be 2 years in duration (in obese and overweight patients) and one as a 1-year study (in obese and overweight patients with type 2 diabetes). However, the 2-year trials and the CP-945,598 development program were terminated before completion due to changing regulatory perspectives of CB1 receptor-related drugs. In total, 1,253 and 2,536 participants in the two 2-year multinational and North American studies were randomized to 10-mg CP-945,598 (n = 360; 718); 20-mg CP-945,598 (n = 534, 1,084) and placebo (n = 359, 734), respectively; and 975 participants were randomized to 10-mg CP-945,598 (n = 318); 20-mg CP-945,598 (n = 320); and placebo (n = 337) in the 1-year multinational diabetes trial. Baseline demographics were similar between treatment groups within each trial. One year of treatment with CP-945,598 resulted in a dose-related mean percentage reduction from baseline body-weight in all trials. A significant proportion of all participants also achieved 5% and 10% weight loss after 1 year. In participants with mainly well-controlled type 2 diabetes, the combination of lifestyle and CP-945,598 induced substantial improvements in glycemic control. The most frequent adverse events (AEs) for CP-945,598 were: diarrhea, nausea, nasopharyngitis, and headache. Self-reported experiences of anxiety and suicidal thoughts were higher with CP-945,598 than placebo, as were the incidence of depression and depressed mood. However, the reported increases in psychiatric symptoms were not consistently dose dependent.

Predictors of weight loss and maintenance in patients treated with antiobesity drugs

BACKGROUND

The prevalence of obesity and related diseases has increased enormously in the last few decades, becoming a very important medical and social issue. Because of the increasing number of people who need weight loss therapies and the high costs associated with these, the search for reliable predictors of success for weight loss and weight maintenance treatments has become a priority.

OBJECTIVE

A literature review was undertaken to identify possible predictors of outcome of weight loss and weight maintenance in patients treated with antiobesity drugs.

RESULTS

For the majority of variables, published data are not sufficient to define their role on final outcomes. Among all considered factors, only early response to treatment appeared to be a reliable positive predictor, and diabetes a negative predictor of weight loss and maintenance.

CONCLUSION

To date, no definitive results have been obtained. Due to the great benefits of reliable predictors of outcome associated to currently available antiobesity drugs and those under development, identifying these predictors has to be supported and encouraged.

Proof-of-concept trial on the efficacy of sodium tungstate in human obesity

AIM

Considering the poor long-term success of current dietary and pharmacological interventions, we aimed to evaluate the potential effect of sodium tungstate in the treatment of grade I and II obesity (ClinicalTrials.gov identifier: NCT00555074).

METHODS

Prospective, randomized, placebo-controlled, double-blind, proof-of-concept study was carried out. Following a 2-week lead-in period, 30 obese (body mass index, BMI 30.0-39.9 kg/m(2)), non-diabetic subjects were randomized to receive either sodium tungstate (100 mg bid) or placebo for 6 weeks. The primary study endpoint was the absolute change in body weight relative to the time of randomization.

RESULTS

Treatment with sodium tungstate [-0.135 ± 0.268 kg (95% CI -0.686 to +0.416 kg)] was not associated with a significant weight loss compared to placebo [-0.063 ± 0.277 kg (95% CI -0.632 to +0.507 kg)] (p = 0.854). Likewise, treatment with sodium tungstate was not associated with significant changes in fat mass (DEXA), resting energy expenditure (indirect calorimetry) or caloric consumption (3-day food records).

CONCLUSION

Our data do not support sodium tungstate as a pharmacological agent in the treatment of human obesity.

Initial weight loss on an 800-kcal diet as a predictor of weight loss success after 8 weeks: the Diogenes study

OBJECTIVE

The purpose of this study was to investigate whether pre-treatment subject characteristics and weight change during the first weeks of a low-calorie diet (LCD) can predict weight loss outcomes at the end of a controlled 8-week weight loss period in overweight and obese adults.

SUBJECTS

A total of 932 overweight and obese subjects of both genders were included at eight European centers, and underwent an 8-week LCD period.

RESULTS

The weight loss at week 8 was positively correlated with initial body weight (Spearman's rho=0.62), height (rho=0.43), body mass index (rho=0.43), waist (rho=0.48) and hip circumference (rho=0.33), sagittal diameter (rho=0.45), fat mass (rho=0.35) and fat-free mass (rho=0.52), and gender (rho=-0.36) (all P<0.01). In the multivariate regression model, adjusted for center, only initial body weight, early weight loss (week 1) and weight loss at week 3 were significant predictors of weight loss outcome at week 8: weight loss (kg) at week 8=0.09+0.046 x baseline body weight (kg)-0.311 x weight loss (kg) at week 1+1.284 x weight loss (kg) at week 3 (R(2)=68%, P<0.0001). A weight loss of > or =2.6 kg at week 1 during the LCD period was identified as the optimal cut-off predictor for at least 10 kg weight loss at week 8.

CONCLUSIONS

This study suggests that initial body weight, early weight loss (week 1) and weight loss at week 3 are predictors of final weight loss during an 8-week LCD, and may be used as early biomarkers of subsequent responses to an LCD diet.

The weight lowering effect of sibutramine and its impact on serum lipids in cardiovascular high risk patients with and without type 2 diabetes mellitus - an analysis from the SCOUT lead-in period

BACKGROUND

Obesity, type 2 diabetes mellitus (T2D) and unhealthy blood lipid profile are strongly associated with the risk of developing cardiovascular disease (CVD). We examined whether blood lipid changes with short term administration of the weight lowering drug, sibutramine and lifestyle modification in obese and overweight high-risk patients was associated with T2D status at screening.

METHODS

The Sibutramine Cardiovascular OUTcomes (SCOUT) trial included obese and overweight patients at increased risk of cardiovascular events. All patients received guidance on diet and exercise plus once-daily 10 mg sibutramine during the 6-week, single blind lead-in period. Multivariable regression models were used to investigate factors associated with changes in lipid levels during the first four weeks of treatment.

RESULTS

A total of 10 742 patients received at least one dose of sibutramine during the 6-week lead-in period of SCOUT. After four weeks, patients experienced mean reductions in low density lipoprotein (LDL-C) 0.19 mmol/L, high density lipoprotein (HDL-C) 0.019 mmol/L, very low density lipoprotein (VLDL-C) 0.08 mmol/L, total cholesterol (TC) 0.31 mmol/L and triglycerides 0.24 mmol/L (p < 0.0001 for each). Four week changes in LDL-C, HDL-C and total cholesterol for patients without vs. with T2D were: LDL-C:-0.25 mmol/L vs. -0.18 mmol/L, P = 0.0004; HDL-C: -0.03 mmol/L vs. -0.02 mmol/L, P = 0.0014; total cholesterol: -0.37 mmol/l vs. -0.29 mmol/l, P = 0.0009. Multivariable regression analysis showed that similar decreases in body mass index (BMI) affected lipid changes differently according to diabetes status. A 1 kg/m2 decrease in BMI in patients with T2D was associated with -0.09 mmol/L in LDL-C (P < 0.0001) and -0.01 mmol/L in HDL-C (P = 0.0001) but larger changes of -0.16 mmol/L LDL-C and -0.03 mmol/L in HDL-C (P < 0.0001 for both) in patients without T2D.

CONCLUSION

Short term weight management with sibutramine therapy in obese or overweight high-risk patients induced significant mean reductions for all lipids. Those without T2D benefited most. Patients with hyperlipidaemia and the less obese patients also had greater falls in LDL-C and TC during weight loss. The trial is registered at ClinicalTrial.gov number: NCT00234832.

Weight and blood pressure response to weight management and sibutramine in diabetic and non-diabetic high-risk patients: an analysis from the 6-week lead-in period of the sibutramine cardiovascular outcomes (SCOUT) trial

OBJECTIVE

To assess treatment responses to sibutramine and weight management in diabetic patients during the lead-in period of the Sibutramine Cardiovascular OUTcomes (SCOUT) trial.

METHODS

SCOUT is an ongoing, prospective, randomized, double-blind, placebo-controlled outcome trial in cardiovascular high-risk overweight/obese patients. A total of 10 742 patients received single-blind sibutramine and individualized weight management during the 6-week lead-in period; 84% had a history of type 2 diabetes mellitus and additional co-morbidities. Post-hoc analyses assessed anthropomorphic and vital sign responses between patients with and without diabetes.

RESULTS

Concomitant antidiabetic medication use was reported by 86% of the diabetic patients (approximately 30% required insulin-alone or in combination). Body weight and waist circumference decreased in diabetic patients: median 2.1 kg; 2.0 cm (both men and women); for those on insulin: 1.9 kg; 1.5/2.0 cm (men/women); without insulin: 2.3 kg; 2.0 cm (both men and women); blood pressure (BP) was also reduced (median systolic/diastolic 3.5/1.0 mmHg) with larger reductions in diabetic patients who were hypertensive and/or lost the most weight (>5%). In diabetic patients who entered with BP at target (<130/<85 mmHg) but did not lose weight (N = 245), increases of 3.5/2.0 mmHg were observed. Non-diabetic patients had greater weight losses (2.5 kg) but smaller reductions in BP (systolic/diastolic -2.5/-0.5 mmHg). Pulse rate increases were less in diabetic vs. non-diabetic patients (1.5 vs. 2.0 bpm).

CONCLUSION

In these high-risk diabetic patients, sibutramine and lifestyle modifications for 6 weeks resulted in small, but clinically relevant, median reductions in body weight, waist circumference and BP. A small median increase in pulse rate was recorded.

Comparison of dietary conjugated linoleic acid with safflower oil on body composition in obese postmenopausal women with type 2 diabetes mellitus

BACKGROUND

Weight loss may improve glucose control in persons with type 2 diabetes. The effects of fat quality, as opposed to quantity, on weight loss are not well understood.

OBJECTIVE

We compared the effects of 2 dietary oils, conjugated linoleic acid (CLA) and safflower oil (SAF), on body weight and composition in obese postmenopausal women with type 2 diabetes.

DESIGN

This was a 36-wk randomized, double-masked, crossover study. Fifty-five obese postmenopausal women with type 2 diabetes received SAF or CLA (8 g oil/d) during two 16-wk diet periods separated by a 4-wk washout period. Subjects met monthly with the study coordinator to receive new supplements and for assessment of energy balance, biochemical endpoints, or anthropometric variables.

RESULTS

Thirty-five women completed the 36-wk intervention. Supplementation with CLA reduced body mass index (BMI) (P = 0.0022) and total adipose mass (P = 0.0187) without altering lean mass. The effect of CLA in lowering BMI was detected during the last 8 wk of each 16-wk diet period. In contrast, SAF had no effect on BMI or total adipose mass but reduced trunk adipose mass (P = 0.0422) and increased lean mass (P = 0.0432). SAF also significantly lowered fasting glucose (P = 0.0343) and increased adiponectin (P = 0.0051). No differences were observed in dietary energy intake, total fat intake, and fat quality in either diet period for either intervention.

CONCLUSIONS

Supplementation with CLA and SAF exerted different effects on BMI, total and trunk adipose mass, and lean tissue mass in obese postmenopausal women with type 2 diabetes. Supplementation with these dietary oils may be beneficial for weight loss, glycemic control, or both.

The use of sibutramine in the management of obesity and related disorders: an update

Aims:

To review the major trials that evaluated the efficacy and safety of the use of sibutramine for weight loss and the impact of this agent on obesity-related disorders.

Methods and results:

The most important articles on sibutramine up to January 2009 were located by a PubMed and Medline search. Sibutramine reduces food intake and body weight more than placebo and has positive effects on the lipid profile (mainly triglycerides and high density lipoprotein cholesterol), glycemic control and inflammatory markers in studies for up to one year. Preliminary studies showed that sibutramine may also improve other obesity-associated disorders such as polycystic ovary syndrome, left ventricular hypertrophy, binge eating disorder and adolescent obesity. The high discontinuation rates and some safety issues mainly due to the increase in blood pressure and pulse rate have to be considered. Additionally, it has not yet been established that treatment with sibutramine will reduce cardiovascular events and total mortality.

Conclusions:

Sibutramine, in conjunction with lifestyle measures, is a useful drug for reducing body weight and improving associated cardiometabolic risk factors and obesity-related disorders. Studies of longer duration are required to determine the precise indications of the drug, to evaluate safety issues and to assess its efficacy on cardiovascular mortality.

Predictors of attrition and weight loss success: Results from a randomized controlled trial

Attrition is a common problem in weight loss trials. The present analysis examined several baseline and early-treatment process variables, as predictors of attrition and outcome in a clinical trial that combined pharmacotherapy and behavior therapy for weight loss. Participants were 224 obese adults who were treated with sibutramine alone, lifestyle modification alone, combined therapy, or sibutramine plus brief lifestyle modification. Predictors included baseline characteristics (e.g., demographic, weight-related, psychological, and consumption-related variables), plus attendance, adherence, and weight loss in the early weeks of treatment. Outcomes were attrition and weight loss success (i.e., >or=5% reduction in body weight) at 1 year. Multivariable models, adjusting for other relevant variables, found that younger age and greater baseline depressive symptoms were related to increased odds of attrition (ps <or= 0.003). Greater early weight loss marginally reduced the odds of attrition (p = 0.06). Predictors of weight loss success at 1 year were Caucasian ethnicity (p = 0.04), lower baseline depressive symptoms (p = 0.04), and weight loss during the first 3 weeks of treatment (p < 0.001). Thus, depressive symptoms at baseline were a significant predictor of both attrition and weight loss success. As a process variable, early weight loss appears to have more predictive value than early attendance at treatment sessions or early adherence.

5-HT(1A) activation counteracts cardiovascular but not hypophagic effects of sibutramine in rats

The noradrenaline (NA) and serotonin reuptake inhibitor, sibutramine, gives effective weight loss, but full efficacy cannot be attained at approved doses due to cardiovascular side effects. We assessed in rats the contributions of NA and serotonin transporters to sibutramine's hypophagic and cardiovascular effects, and whether selective 5-hydroxytryptamine (5-HT(1A)) receptor activation could counteract the latter without affecting the former. Food intake was assessed in freely feeding rats and cardiovascular parameters in conscious telemetered rats. Ex vivo radioligand binding was used to estimate brain monoamine transporter occupancy. Sibutramine (1-10 mg/kg p.o.) dose-dependently reduced food intake; however, 10 mg/kg p.o. markedly elevated blood pressure and heart rate. Sibutramine gave greater occupancy of NA than serotonin reuptake sites. Coadministration of the selective 5-HT(1A) agonist F-11440 (2.5 mg/kg p.o.) attenuated sibutramine-induced hypertension and tachycardia without altering its food intake effects. The selective NA reuptake inhibitors, nisoxetine or reboxetine, did not alter food intake alone, but each reduced food intake when combined with F-11440. These results suggest that sibutramine-induced hypophagic and cardiovascular effects are largely due to increased brain synaptic NA via NA reuptake inhibition, and that 5-HT(1A) activation can counter the undesirable cardiovascular effects resulting from increased sympathetic activity. Selective NA reuptake inhibitors did not reduce food intake alone but did when combined with 5-HT(1A) activation. Hence increased synaptic serotonin, via serotonin reuptake inhibition or 5-HT(1A) activation, together with increased NA, would appear to produce hypophagia. Thus weight loss with minimal cardiovascular risk could be achieved by 5-HT(1A) activation combined with NA transporter blockade.

A controlled pharmacogenetic trial of sibutramine on weight loss and body composition in obese or overweight adults

BACKGROUND & AIMS

Weight loss in response to sibutramine is highly variable. We assessed the association of specific markers of polymorphisms of candidate alpha2A adrenoreceptor, 5-HT transporter, and GNbeta3 genes and weight loss with sibutramine.

METHODS

We conducted a randomized, double-blind, pharmacogenetic study of behavioral therapy and sibutramine (10 or 15 mg daily) or placebo for 12 weeks in 181 overweight or obese participants. We measured body weight, body mass index, body composition, gastric emptying, and genetic variation (alpha2A C1291G, 5-HTTLPR, and GNbeta3 C825T genotypes). Analysis of covariance was used to assess treatment effects on and associations of the specific markers of candidate genes with weight loss and body composition.

RESULTS

Sibutramine, 10 and 15 mg, caused weight loss (P = .009); there was a statistically significant gene by dose interaction for GNbeta3 genotype. For each candidate gene, significant treatment effects at 12 weeks were observed (P < .017) for all specific genotype variants (Delta weight loss in the 2 sibutramine doses vs placebo): alpha2A CC (Delta, approximately 5 kg), GNbeta3 TC/TT (Delta, approximately 6 kg), and 5-HTTLPR LS/SS (Delta, approximately 4.5 kg). Gene pairs resulted in significantly greater sibutramine treatment effects on weight (both P < .002): in participants with 5-HTTLPR LS/SS with GNbeta3 TC/TT; Delta, approximately 6 kg and those with alpha2A CC with GNbeta3 TC/TT; Delta, approximately 8 kg; however, effects were not synergistic. Treatment with sibutramine also resulted in significantly greater reduction of body fat for specific alpha2A CC and GNbeta3 TC/TT genotype variants individually (both P < .02).

CONCLUSIONS

Patient selection based on candidate genes may enhance response to multidimensional sibutramine and behavioral therapy for obesity.

Who will lose weight on sibutramine and orlistat? Psychological correlates for treatment success

AIM

To study the associations between weight loss with sibutramine and orlistat with psychological aspects that may interact with patients' response to these drugs.

METHODS

A total of 478 obese patients with a mean body mass index of 42 +/- 12 kg/m(2) gave self-reported, retrospective data on different types of previous weight loss treatments (sibutramine and orlistat, and Weight Watchers used as a control condition) including the amount of weight lost with these treatments, eating behaviour (Dutch Eating Behaviour Questionnaire) and personality (NEO Personality Inventory - Revised).

RESULTS

Greater weight loss with sibutramine was associated with lower levels of restrained eating and higher levels of 'neuroticism', in particular 'anxiety' and 'depression'. Greater weight loss with orlistat was associated with aspects of the personality dimension 'conscientiousness' (e.g. 'order' and 'deliberation').

CONCLUSION

Sibutramine may exert its greatest effect in patients whose eating is a 'natural' response to hunger rather than regulated by cognitions and conscious controls. Patients with low levels of restraint could be more sensitive to the satiety-enhancing effect of sibutramine. They may be able to reduce their food intake without cognitive interference and/or start to control their eating most radically in response to enhanced satiety. Enhanced satiety may also help patients withstand a wish to eat triggered by psychological distress. Possible central nervous system effects on mood could also have reduced eating, which was related to distress. The administration regimen of orlistat is more demanding, requiring greater adherence. This can account for the finding that personality attributes such as conscientiousness are important for success.

A prospective study of predictors of successful weight maintenance by women enrolled in community-based weight-loss programs

OBJECTIVE

Research is limited on the psychological predictors of successful long-term weight maintenance after weight loss. Therefore, the present study examined the individual contributions of body image, depression, and self-esteem to successful weight maintenance after a significant weight loss.

METHOD

Measures of depression, self-esteem, and body image were administered at baseline, three-, and twelve-months to 73 women enrolled in community- based weight loss programs.

RESULTS

Significant predictors of weight maintenance included baseline self-classified weight, early (3 months) weight maintenance, later (12 months) change in perceptual body image, and the interaction between early and late change in body image avoidance. Classifying oneself as more overweight at baseline predicted less weight maintenance, while later discrepancies between current and realistic body size were positively associated with weight maintenance. Those who showed steady improvements in body image avoidance behavior were more likely to maintain weight loss. Baseline BMI, self-esteem, and depression did not predict 12-month weight maintenance.

DISCUSSION

Further understanding how body image and related factors contribute to weight maintenance may inform development of more effective interventions to promote long-term weight maintenance.

Treatment modalities of obesity: what fits whom?

The prevalence of obesity is increasing in both developed and developing countries, with rates reaching approximately 10-35% among adults in the Euro-American region. Obesity is associated with increased risks of cardiovascular diseases, type 2 diabetes, arthritis, and some type of cancers. Obesity significantly affects the quality of life and reduces the average life expectancy. The effective treatment of obesity should address both the medical and the social burden of this disease. Obesity needs to be treated within the health care system as any other complex disease, with empathy and without prejudice. Both health care providers and patients should know that the obesity treatment is a lifelong task. They should also set realistic goals before starting the treatment, whereas keeping in mind that even a modest weight loss of 5-15% significantly reduces obesity-related health risks. Essential treatment of obesity includes low-calorie low-fat diets, increased physical activity, and strategies contributing to the modification of lifestyle. Anti-obesity drugs facilitate weight loss and contribute to further amelioration of obesity-related health risks. A short-term weight loss, up to 6 months, is usually achieved easily. However, the long-term weight management is often associated with a lack of compliance, failures, and a high dropout rate. Regular physical activity, cognitive behavioral modification of lifestyle, and administration of anti-obesity drugs improve weight loss maintenance. Bariatric surgery is an effective strategy to treat severely obese patients. Bariatric surgery leads to a substantial improvement of comorbidities as well as to a reduction in overall mortality by 25-50% during the long-term follow-up. Obesity treatment should be individually tailored and the following factors should be taken into account: sex, the degree of obesity, individual health risks, psychobehavioral and metabolic characteristics, and the outcome of previous weight loss attempts. In the future, an evaluation of hormonal and genetic determinants of weight loss could also contribute to a better choice of individual therapy for a particular obese patient. A multilevel obesity management network of mutually collaborating facilities should be established to provide individually tailored treatment. Centers of excellence in obesity management represented by multidisciplinary teams should provide comprehensive programs for the treatment of obesity derived from evidence-based medicine.

Adipose gene expression prior to weight loss can differentiate and weakly predict dietary responders

BACKGROUND

The ability to identify obese individuals who will successfully lose weight in response to dietary intervention will revolutionize disease management. Therefore, we asked whether it is possible to identify subjects who will lose weight during dietary intervention using only a single gene expression snapshot.

METHODOLOGY/PRINCIPAL FINDINGS

The present study involved 54 female subjects from the Nutrient-Gene Interactions in Human Obesity-Implications for Dietary Guidelines (NUGENOB) trial to determine whether subcutaneous adipose tissue gene expression could be used to predict weight loss prior to the 10-week consumption of a low-fat hypocaloric diet. Using several statistical tests revealed that the gene expression profiles of responders (8-12 kgs weight loss) could always be differentiated from non-responders (<4 kgs weight loss). We also assessed whether this differentiation was sufficient for prediction. Using a bottom-up (i.e. black-box) approach, standard class prediction algorithms were able to predict dietary responders with up to 61.1%+/-8.1% accuracy. Using a top-down approach (i.e. using differentially expressed genes to build a classifier) improved prediction accuracy to 80.9%+/-2.2%.

CONCLUSION

Adipose gene expression profiling prior to the consumption of a low-fat diet is able to differentiate responders from non-responders as well as serve as a weak predictor of subjects destined to lose weight. While the degree of prediction accuracy currently achieved with a gene expression snapshot is perhaps insufficient for clinical use, this work reveals that the comprehensive molecular signature of adipose tissue paves the way for the future of personalized nutrition.

[Treatment of type 2 diabetes: revision of current therapeutical options and priorities]

The paradigm of type 2 diabetes mellitus treatment is based in an adequate meal plan and the regular practice of physical exercise. The benefits of these measures are of evident as it is the perseverance in their compliance. In the daily practice, this reality favours the early implementation of a pharmacological therapy that, in the opinion of different experts, would be simultaneous to the introduction of life style changes. In the last years, new drugs have been developed. On the one hand, there are agents with beneficial effects not only on blood glucose control but also on the components of metabolic syndrome. Other drugs, according to different experts, have doubtful therapeutical contribution. The appearance of new drugs to treat obesity, associated with diabetes or not, extends other possibilities of choice to take into account. The great variety of options makes the decision of the adequate therapy more difficult. In the last decade, many therapeutic guidelines have been developed, with convergences and divergences that may mislead the inexpert practitioners. In this review we propose some practical advise in diet and exercise, and an evaluation of the different drugs and rules of intervention proposed in the different therapeutic guidelines. The ultimate goal is to facilitate and direct type 2 diabetes management.

Obesity: which drug and when?

BACKGROUND

Obesity, with all its consequences, is audaciously confronting medical professionals and health service providers worldwide. Diet and exercise intervention is an essential part of any weight management strategy, but may not succeed in isolation. Effective approaches for routine practice are more likely to involve affordable, efficacious and well-tolerated drug therapy than the more expensive, case selective approach of bariatric surgery.

OBJECTIVES AND CONCLUSIONS

Advancement of pharmacotherapy is expanding the battery of available drugs; the clinician is faced with an increasingly complex therapeutic decision. Which drug to use, and when, is influenced by a range of factors, discussed here. There is a large body of high quality evidence in the literature to support the presently available drugs; however, many questions remain unanswered including duration of therapy and whether longer-term goals of improved morbidity and mortality are achievable. Clinician and patient awareness of these issues will provide a more informed therapeutic decision and ultimately improve the potential for reaching the weight management targets.

Abnormal lipid and glucose metabolism in obesity: implications for nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease represents a spectrum of histopathologic abnormalities, the prevalence of which may be as high as 24% of the population of the United States. Nonalcoholic fatty liver disease will play a major role in the science and practice of gastroenterology in the near future. The fundamental derangement in nonalcoholic fatty liver disease is insulin resistance, a key component of the metabolic syndrome, which includes type 2 diabetes mellitus, hypertriglyceridemia, essential hypertension, low circulating high-density lipoprotein, and obesity. The natural history of fatty liver disease is not always benign, and causality for cirrhosis and chronic liver disease is well-founded in the literature. Treatment strategies are limited and, at present, are primarily focused on weight loss and use of insulin sensitizing agents, including the thiazolidenediones. Recent data clearly implicate hepatic insulin resistance as a culprit in accumulation of free fatty acids as triglycerides in hepatocytes. Hepatic insulin resistance is clearly exacerbated by systemic insulin resistance and impaired handling by skeletal muscle and adipose tissue of both glucose and free fatty acids. The key consequence of hepatic insulin resistance, impaired hepatocyte insulin signal transduction, results in adverse cellular and molecular changes exacerbating hepatocyte triglyceride storage. Cytokines secreted by white adipose tissue, adipokines, have emerged as key players in glucose and fat metabolism previously thought controlled largely by insulin. Modulation of adipokines may aid in further understanding of the pathophysiology and treatment of nonalcoholic fatty liver disease.