Clinical efficacy of a medically supervised outpatient high-protein, low-calorie diet program is equivalent in prediabetic, diabetic and normoglycemic obese patients

A high-protein total diet replacement alters the regulation of food intake and energy homeostasis in healthy, normal-weight adults

PURPOSE

Dietary intake can affect energy homeostasis and influence body weight control. The aim of this study was to compare the impact of high-protein total diet replacement (HP-TDR) versus a control (CON) diet in the regulation of food intake and energy homeostasis in healthy, normal-weight adults.

METHODS

In this acute randomized controlled, cross-over study, participants completed two isocaloric arms: a) HP-TDR: 35% carbohydrate, 40% protein, and 25% fat; b) CON: 55% carbohydrate, 15% protein, and 30% fat. The diets were provided for 32 h while inside a whole-body calorimetry unit. Appetite sensations, appetite-related hormones, and energy metabolism were assessed.

RESULTS

Forty-three healthy, normal-weight adults (19 females) participated. Appetite sensations did not differ between diets (all p > 0.05). Compared to the CON diet, the change in fasting blood markers during the HP-TDR intervention was smaller for peptide tyrosine-tyrosine (PYY; - 18.9 ± 7.9 pg/mL, p = 0.02) and greater for leptin (1859 ± 652 pg/mL, p = 0.007). Moreover, postprandial levels of glucagon-like peptide 1 (1.62 ± 0.36 pM, p < 0.001) and PYY (31.37 ± 8.05 pg/mL, p < 0.001) were higher in the HP-TDR. Significant correlations were observed between energy balance and satiety (r = - 0.41, p = 0.007), and energy balance and PFC (r = 0.33, p = 0.033) in the HP-TDR.

CONCLUSION

Compared to the CON diet, the HP-TDR increased blood levels of anorexigenic hormones. Moreover, females and males responded differently to the intervention in terms of appetite sensations and appetite-related hormones.

TRIAL REGISTRATION

NCT02811276 (retrospectively registered on 16 June 2016) and NCT03565510 (retrospectively registered on 11 June 2018).

Association of a Self-Paid Medically Supervised Weight Management Program with Reversal of Obesity-Associated Impaired Fasting Glucose

Aims: The progression of prediabetes to T2DM can be delayed through diet modification and weight management. However, the intensive lifestyle program is often not covered by medical insurance. This retrospective analysis evaluates the association of a patient self-paid weight management program on an improvement of blood sugar in overweight and obese patients with impaired fasting glucose (IFG). Methods: The medical records of 4634 patients who participated in the self-pay UCLA Weight Management Program were reviewed and 2572 patients met the criteria for this retrospective analysis to examine whether this program was associated with the reversal of IFG over 3 months among 1396 patients with normal fasting glucose (NFG) and 1176 with IFG. Results: The patients with IFG lost comparable amounts of weight (10.5 ± 1.3 kg) at three months, as did the subjects with NFG (10.1 ± 1.3 kg). Fasting blood glucose in the IFG group decreased from 108.49 ± 6.4 to 101.8 ± 9.41 mg/dL (p < 0.0001) after three months. There were also significant reductions in triglycerides, and both systolic and diastolic blood pressure in both groups in association with weight loss. Conclusion: Our medically supervised self-pay multidisciplinary weight management program was associated with reduced fasting blood glucose levels in patients with IFG over three months with comparable weight loss to patients with NFG.

Efficiency of a 15-Week Weight-Loss Program, Including a Low-Calorie Formula Diet, on Glycemic Control in Patients with Type 2 Diabetes Mellitus and Overweight or Obesity

INTRODUCTION

Patients who are overweight or obese have an increased risk of developing type 2 diabetes mellitus (T2DM). Weight loss can have a positive effect on glycemic control.

OBJECTIVE

We aimed to investigate glycemic control in patients with T2DM and overweight or obesity during a structured weight-loss program.

METHODS

This was a prospective, interventional study. We recruited 36 patients (14 men and 22 women) with a median age of 58.5 years and median body mass index (BMI) of 34.1, to a 15-week structured weight-loss program with a low-calorie (800 kcal) formula diet for 6 weeks. The primary end point, HbA1c level, and secondary end points, anthropometric data, medication, and safety, were assessed weekly. Laboratory values and quality of life were assessed at baseline and after 15 weeks.

RESULTS

HbA1c decreased from 7.3% at baseline to 6.5% at 15 weeks (p < 0.001), median body weight by 11.9 kg (p < 0.001), median BMI by 4.3 (p < 0.001) and median waist circumference by 11.0 cm (p < 0.001). Two participants discontinued insulin therapy, 4 could reduce their dosage of oral antidiabetic agents, and 6 completely discontinued their antidiabetic medication. Insulin dose decreased from 0.63 (0.38-0.89) to 0.39 (0.15-0.70) units/kg body weight (p < 0.001). No patient experienced hypoglycemic episodes or hospital emergency visits. Triglycerides and total cholesterol decreased as well as surrogate markers of liver function. However, the levels of high-density and low-density lipoprotein cholesterol (HDL-C and LDL-C) as well as uric acid remain unchanged. Regarding quality of life, the median physical health score increased from 44.5 (39.7-51.4) at baseline to 48.0 (43.1-55.3; p = 0.007), and the median mental health score decreased from 42.1 (36.1-46.7) to 37.4 (30.3-43.7; p = 0.004).

CONCLUSIONS

A structured weight-loss program is effective in the short term in reducing HbA1c, weight, and antidiabetic medication in patients with T2DM who are overweight or obese. Levels of HDL-C and LDL-C were not affected by short-term weight loss. The decline in mental health and the long-term effects of improved glycemic control require further trials.

A high-protein total diet replacement increases energy expenditure and leads to negative fat balance in healthy, normal-weight adults

BACKGROUND

High-protein diets and total diet replacements are becoming increasingly popular for weight loss; however, further research is needed to elucidate their impact on the mechanisms involved in weight regulation.

OBJECTIVE

The aim of this inpatient metabolic balance study was to compare the impact of a high-protein total diet replacement (HP-TDR) versus a control diet (CON) on select components of energy metabolism in healthy adults of both sexes.

METHODS

The acute intervention was a randomized, controlled, crossover design with participants allocated to 2 isocaloric arms: 1) HP-TDR: 35% carbohydrate, 40% protein, and 25% fat achieved through a nutritional supplement; 2) CON: 55% carbohydrate, 15% protein, and 30% fat. Participants received the prescribed diets for 32 h while inside a whole-body calorimetry unit (WBCU). The first dietary intervention randomly offered in the WBCU was designed to maintain energy balance and the second matched what was offered during the first stay. Energy expenditure, macronutrient oxidation rates and balances, and metabolic blood markers were assessed. Body composition was measured at baseline using DXA.

RESULTS

Forty-three healthy, normal-weight adults (19 females and 24 males) were included. Compared with the CON diet, the HP-TDR produced higher total energy expenditure [(EE) 81 ± 82 kcal/d, P <0.001], protein and fat oxidation rates (38 ± 34 g/d, P <0.001; 8 ± 20 g/d, P = 0.013, respectively), and a lower carbohydrate oxidation rate (-38 ± 43 g/d, P <0.001). Moreover, a HP-TDR led to decreased energy (-112 ± 85 kcal/d; P <0.001), fat (-22 ± 20 g/d; P <0.001), and carbohydrate balances (-69 ± 44 g/d; P <0.001), and increased protein balance (90 ± 32 g/d; P <0.001).

CONCLUSIONS

Our primary findings were that a HP-TDR led to higher total EE, increased fat oxidation, and negative fat balance. These results suggest that a HP-TDR may promote fat loss compared with a conventional isocaloric diet. These trials were registered at clinicaltrials.gov as NCT02811276 and NCT03565510.

Scientific evidence underlying contraindications to the ketogenic diet: An update

First identified as a feasible treatment for intractable epilepsy, the ketogenic diet (KD) has recently gained popularity thanks to growing evidence on applications such as weight loss, most importantly, but also NAFLD, cancer, neurologic conditions and chronic pain. As with any treatment, whether pharmacologic or not, the KD might not be an appropriate intervention for every individual, and a number of contraindications have been proposed, now deeply rooted into clinical practice, excluding de facto many patients that could benefit from its use. However, many of these concerns were expressed due to the absence of clinical studies conducted on fragile populations, and an assessment of lately emerged evidence relative to KD safety is currently lacking and much needed. We herein provide a critical revision of the literature behind each safety alert, in order to guide through the treatment options in the case of subjects with an indication to the KD and a borderline safe situation. Based on available evidence, the possible use of this diet as a therapeutic intervention should be assessed on a patient-to-patient basis by adequately skilled medical doctors, keeping in mind current recommendations, but reading them through the knowledge of the current state of the art.

A position statement on screening and management of prediabetes in adults in primary care in Australia

Prediabetes has a high prevalence, with early detection essential to facilitate optimal management to prevent the development of conditions such as type 2 diabetes and cardiovascular disease. Prediabetes can include impaired fasting glucose, impaired glucose tolerance and elevated HbA1c. This position statement outlines the approaches to screening and management of prediabetes in primary care. There is good evidence to implement intensive, structured lifestyle interventions for individuals with impaired glucose tolerance. The evidence for those with impaired fasting glucose or elevated HbA1c is less clear, but individuals should still be provided with generalised healthy lifestyle strategies. A multidisciplinary approach is recommended to implement healthy lifestyle changes through education, nutrition and physical activity. Individuals should aim to lose weight (5-10% of body mass) using realistic and sustainable dietary approaches supported by an accredited practising dietitian, where possible. Physical activity and exercise should be used to facilitate weight maintenance and reduce blood glucose. Moderate-vigorous intensity aerobic exercise and resistance training should be prescribed by an accredited exercise physiologist, where possible. When indicated, pharmacotherapy, metabolic surgery and psychosocial care should be considered, in order to enhance the outcomes associated with lifestyle change. Individuals with prediabetes should generally be evaluated annually for their diabetes status.

Effect of a Behavioral Weight Loss Intervention in People With Serious Mental Illness and Diabetes

OBJECTIVE

Given the high prevalence of obesity and diabetes in patients with serious mental illness (SMI) and the lack of evidence on the effects of weight loss programs in SMI patients with diabetes, we evaluated the effectiveness of a behavioral weight loss intervention among SMI participants with and without diabetes.

RESEARCH DESIGN AND METHODS

Using data from ACHIEVE, a randomized controlled trial to evaluate the effects of a behavioral weight loss intervention among overweight/obese people with SMI, we assessed and compared weight change from baseline to 18 months in participants with and without diabetes using a longitudinal mixed-effects model.

RESULTS

Of the 291 trial participants, 82 (28.2%) participants had diabetes (34 and 48 in intervention and control groups, respectively) at baseline. Participants with diabetes were more likely to be taking antipsychotics (31.7% vs. 18.7%, P = 0.02). At 18 months, participants in the control group with diabetes lost 1.2 lb (0.6%) of body weight compared with 0.8 lb (0.7%) among those without diabetes. In the intervention group, participants with diabetes lost 13.7 lb (6.6%) of their initial body weight compared with 5.4 lb (2.9%) for those without diabetes. Corresponding net effects (intervention minus control) were 4.6 lb (2.2%) and 12.5 lb (6.0%) net weight reduction over 18 months in the no diabetes and the diabetes subgroups, respectively. However, the between-group difference in intervention effects was statistically nonsignificant (absolute weight change: P-interaction = 0.08; % weight change: P-interaction = 0.10).

CONCLUSIONS

A behavioral weight loss intervention is effective among overweight and obese individuals with SMI regardless of their diabetes status.

Treating prediabetes: why and how should we do it?

Prediabetes is the subclinical impairment in fasting plasma glucose, impaired glucose tolerance or both. The degree of impairment is between euglycemia and the hyperglycemia of type 2 diabetes (T2DM). Prediabetes is not considered benign, because it is a risk factor for T2DM but is also associated with micro and macrovascular complications. Lifestyle interventions including diet and exercise are first-line treatments. Medications can also play a role, as randomized controlled trials of biguanides (metformin) alpha-glucosidase inhibitors (Acarbose), inhibitors of pancreatic lipase (Orlistat), PPAR-gamma agonists (Rosiglitazone, Pioglitazone), meglitinides (Nateglinide) and GLP-1 receptor agonists (Liraglutide) have all shown benefits. Bariatric surgery is another efficacious means of preventing T2DM in patients with prediabetes and obesity. Prediabetes in its various guises is a risk factor for the future development T2DM and diabetic complications. Importantly the prediabetic state is amenable to interventions that prevent/delay transition to overt T2DM. Knowledge gaps exist regarding how best to make prognostication highly sensitive and specific as to which patient will develop T2DM. Moreover, understanding of phenotype specific pathophysiology may add value to funding appropriate interventions for patients with prediabetes. Management of patients with prediabetes should be individualized based on the algorithms that predict phenotype specific risk and allow for the use of phenotype tailored interventions.

A health economic model to assess the cost-effectiveness of OPTIFAST for the treatment of obesity in the United States

OBJECTIVES

Obesity is associated with high direct medical costs and indirect costs resulting from productivity loss. The high prevalence of obesity generates a justified need to identify cost-effective weight loss approaches from a payer's perspective. Within the variety of weight management techniques, OPTIFAST is a clinically recognized and scientifically proven total meal replacement Low Calorie Diet that provides meaningful results in terms of weight loss and reduction in comorbidities. The objective of this study is assess potential cost-savings of the OPTIFAST program in the US, as compared to "no intervention" and pharmacotherapy.

METHODS

An event-driven decision analytic model was used to estimate payer's cost-savings from reimbursement of the 1-year OPTIFAST program over 3 years in the US. The analysis was performed for the broad population of obese persons (BMI >30 kg/m²) undergoing the OPTIFAST program vs liraglutide 3 mg, naltrexone/bupropion and vs "no intervention". The model included the risk of complications related to increased BMI. Data sources included published literature, clinical trials, official US price/tariff lists, and national population statistics. The primary perspective was that of a US payer; costs were provided in 2016 US dollars.

RESULTS

OPTIFAST leads over a period of 3 years to cost-savings of USD 9,285 per class I and II obese patient (BMI 30-39.9 kg/m²) as compared to liraglutide and USD 685 as compared to naltrexone/bupropion. In the same time perspective, the OPTIFAST program leads to a reduction of cost of obesity complications of USD 1,951 as compared to "no intervention", with the incremental cost-effectiveness ratio of USD 6,475 per QALY. Scenario analyses also show substantial cost-savings in patients with class III obesity (BMI ≥ 40.0 kg/m²) and patients with obesity (BMI = 30-39.9 kg/m²) and type 2 diabetes vs all three previous comparators and bariatric surgery.

CONCLUSIONS

Reimbursing OPTIFAST leads to meaningful cost-savings for US payers as compared with "no intervention" and liraglutide and naltrexone/bupropion in obese patients. Similar results can be expected in matching healthcare settings of other countries. Moreover, OPTIFAST has additional clinical and economic advantages through very low complication and adverse events rates.

Comparative effectiveness of a portion-controlled meal replacement program for weight loss in adults with and without diabetes/high blood sugar

BACKGROUND

Individuals with type 2 diabetes (DM2) may be less successful at achieving therapeutic weight loss than their counterparts without diabetes. This study compares weight loss in a cohort of adults with DM2 or high blood sugar (D/HBS) to a cohort of adults without D/HBS. All were overweight/obese and following a reduced or low-calorie commercial weight-loss program incorporating meal replacements (MRs) and one-on-one behavioral support.

SUBJECTS/METHODS

Demographic, weight, body composition, anthropometric, pulse and blood pressure data were collected as part of systematic retrospective chart review studies. Differences between cohorts by D/HBS status were analyzed using Mann-Whitney U-tests and mixed model regression.

RESULTS

A total of 816 charts were included (125 with self-reported D/HBS). The cohort with D/HBS had more males (40.8 vs 25.6%), higher BMI (39.0 vs 36.3 kg m^-2) and was older (56 vs 48 years). Among clients continuing on program, the cohorts with and without D/HBS lost, on average, 5.6 vs 5.8 kg (NS) (5.0 vs 5.6%; P=0.005) of baseline weight at 4 weeks, 11.0 vs 11.6 kg (NS) (9.9 vs 11.1%; P=0.027) at 12 weeks and 16.3 vs 17.1 kg (13.9 vs 15.7%; NS) at 24 weeks, respectively. In a mixed model regression controlling for baseline weight, gender and meal plan, and an intention-to-treat analysis, there was no significant difference in weight loss between the cohorts at any time point. Over 70% in both cohorts lost ⩾5% of their baseline weight by the final visit on their originally assigned meal plan. Both cohorts had significant reductions from baseline in body fat, blood pressure, pulse and abdominal circumference.

CONCLUSION

Adults who were overweight/obese and with D/HBS following a commercial weight-loss program incorporating MRs and one-on-one behavioral support achieved therapeutic weight loss. The program was equally effective for weight loss and reductions in cardiometabolic risk factors among adults with and without D/HBS.

LIMITED CARBOHYDRATE REFEEDING INSTRUCTION FOR LONG-TERM WEIGHT MAINTENANCE FOLLOWING A KETOGENIC, VERY-LOW-CALORIE MEAL PLAN

OBJECTIVE

Weight-loss maintenance following very-low-calorie meal plans is poorly studied. This report describes weight-loss efficacy and predictors of weight-loss maintenance of a ketogenic, very-low-calorie meal plan (protein-sparing modified fast, PSMF) in people with obesity.

METHODS

A total of 127 consecutive adults in the PSMF meal plan (27.2 ± 19.5 weeks) and 48 adults on a conventional, hypocaloric meal plan (23.6 ± 20.8 weeks) were retrospectively studied for percent weight change from baseline to end of intervention and at 6, 12, and 24 months postintervention. Baseline factors were analyzed for correlations with weight-loss maintenance.

RESULTS

At end of intervention, weight loss from baseline was greater for the PSMF group compared to the conventional intervention group (-12.4% vs. -2.6%; P<.001) but was similar between groups by 12 months postintervention. PSMF subjects who attended follow-up visits to receive instruction on gradual and limited carbohydrate refeeding after ketosis saw significant weight loss at the end of PSMF compared to those who did not follow-up to receive instruction (-17.5% vs. -8.0%; P<.001) and maintained greater weight loss through 12 months post-PSMF (-9.8% vs. -1.5%; P<.001). Higher baseline body mass index correlated with less weight loss at 12 months post-PSMF (P = .035).

CONCLUSION

PSMF results in effective short-term weight loss of more than 5% from baseline weight. Follow-up for limited carbohydrate refeeding instruction is important for weight-loss maintenance up to 2 years after initial weight loss.

ABBREVIATIONS

BMI = body mass index; PSMF = protein-sparing modified fast.

Weight losses with low-energy formula diets in obese patients with and without type 2 diabetes: systematic review and meta-analysis

AIM

To provide a systematic review, of published data, to compare weight losses following very low calorie (<800 kcal per day VLCD) or low-energy liquid-formula (>800 kcal per day LELD) diets, in people with and without type 2 diabetes mellitus (T2DM).

METHODS

Systematic electronic searches of Medline (1946-2015) and Embase (1947-2015) to identify published studies using formula total diet replacement diets (VLCD/LELD). Random effects meta-analysis using weighted mean difference (WMD) in body weight between groups (with and without diabetes) as the summary estimate.

RESULTS

Final weight loss, in the five included studies, weighted for study sizes, (n=569, mean BMI=35.5-42.6 kg/m2), was not significantly different between participants with and without T2DM: -1.2 kg; 95% CI: -4.1 to 1.6 kg). Rates of weight loss were also similar in the two groups -0.6 kg per week (T2DM) and 0.5 kg per week (no diabetes), and for VLCD (<800 kcal per day) and LELD (>800 kcal per day).

CONCLUSIONS

Weight losses with liquid-formula diets are very similar for VLCD and LELD and for obese subjects with or without T2DM. They can potentially achieve new weight loss/ maintenance targets of >15-20% for people with severe and medically complicated obesity.

The Protein-Sparing Modified Fast Diet: An Effective and Safe Approach to Induce Rapid Weight Loss in Severely Obese Adolescents

Objectives: The protein-sparing modified fast (PSMF) is a rigorous way of rapidly losing a large amount of weight. Although adult studies have shown the PSMF to be effective, data in adolescents are lacking. The aim of this study was to determine the efficacy and safety of the PSMF in severely obese adolescents. Methods: 12 subjects who were evaluated in the Obesity Management Program at the Cleveland Clinic from 2011 to 2014 were included. The subjects were initiated on the PSMF after failing other conventional methods of weight loss. Once the goal weight was achieved, subjects were transitioned to the refeeding phase for weight maintenance. Results: Follow-up was scheduled at 3-month (11 patients) and 6-month (6 patients) intervals. At the 6-month follow-up visit, the average weight loss was 11.19 kg (95% confidence interval = -5.4, -27.8, P = .028), with average of 9.8% from baseline. Fifty percent of subjects had >5% weight loss and 20% had >10% weight loss. Four patients were lost to the follow-up (40%). An improvement was noted in total cholesterol and high-density lipoprotein. Due to a small sample size these results were not statistically significant. Side effects reported by subjects were mild dehydration due to nausea (2 patients), decreased energy (1 patient), and transient labile mood (1 patient). No life-threatening side effects were reported. Conclusion: Our results show that the PSMF diet can be used as an effective and safe method in the outpatient setting for rapid weight loss in adolescents with severe obesity.

Inhibition of Diethylnitrosamine-Induced Hepatocarcinogenesis in Mice by a High Dietary Protein Intake

Epidemiological and experimental evidence supports the key role of diet in the development of many types of cancer. Recent studies have suggested that dietary modifications may be beneficial for individuals at high risk for hepatocellular carcinoma (HCC). In this study, we investigated the effect of a high-protein (HP; 20% casein) dietondiethylnitrosamine (DEN)-induced hepatocarcinogenesis. Mice were given free access to water with 30 μg/ml DEN and fed a normal or HP diet for 22 wk. The results showed mice consuming HP diets had reduced mortality rates and body weights and lower hepatic enzyme activity compared to DEN-treated mice on a normal diet. HP consumption also promoted collagen accumulation in the liver, and reduced numbers of proliferating hepatocytes and infiltrating inflammatory cells, as well as decreased expression of inflammatory factor interleukin-1β, and nuclear factor κB activation. These data indicate that HP diets can inhibit DEN-induced hepatocarcinogenesis via suppression of the inflammatory response and provide a new evidence for the dietary management of clinical patients with hepatocellular carcinoma.