EXIST: EXamining rIsk of excesS adiposiTy-Machine learning to predict obesity-related complications

Background

Obesity is associated with an increased risk of multiple conditions, ranging from heart disease to cancer. However, there are few predictive models for these outcomes that have been developed specifically for people with overweight/obesity.

Objective

To develop predictive models for obesity-related complications in patients with overweight and obesity.

Methods

Electronic health record data of adults with body mass index 25-80 kg/m2 treated in primary care practices between 2000 and 2019 were utilized to develop and evaluate predictive models for nine long-term clinical outcomes using a) Lasso-Cox models and b) a machine-learning method random survival forests (RSF). Models were trained on a training dataset and evaluated on a test dataset over 100 replicates. Parsimonious models of <10 variables were also developed using Lasso-Cox.

Results

Over a median follow-up of 5.6 years, study outcome incidence in the cohort of 433,272 patients ranged from 1.8% for knee replacement to 11.7% for atherosclerotic cardiovascular disease. Harrell C-index averaged over replicates ranged from 0.702 for liver outcomes to 0.896 for death for RSF, and from 0.694 for liver outcomes to 0.891 for death for Lasso-Cox. The Harrell C-index for parsimonious models ranged from 0.675 for liver outcomes to 0.850 for knee replacement.

Conclusions

Predictive modeling can identify patients at high risk of obesity-related complications. Interpretable Cox models achieve results close to those of machine learning methods and could be helpful for population health management and clinical treatment decisions.

Clinical, economic, and health-related quality of life outcomes in patients with overweight or obesity in the United States: 2016-2018

Objectives

This study aimed to estimate clinical, economic (including productivity), and health-related quality of life (HRQoL) outcomes and associated individual characteristics among adults with overweight (OW) or obesity in the United States.

Methods

This study included adult respondents with body mass index (BMI) ≥18.5 kg/m2 in the 2017-2018 National Health and Nutrition Examination Survey (NHANES) and 2016 Medical Expenditure Panel Survey. Respondents were classified according to BMI. Individual characteristics were described by BMI categories. Multivariable regression models estimated the association between BMI categories and outcomes, adjusting for individual characteristics.

Results

Nearly three-quarters (73.7%) of NHANES participants were OW or obese. Relative to Normal weight (NW), respondents with Class 3 obesity had more obesity-related complications (2.07 vs. 4.62, p < 0.001). Higher BMI was associated with significantly lower HRQoL, lower productivity, and higher healthcare expenditures as well as more frequent weight loss attempts in the previous 12 months. Weight loss surgery and prescription anti-obesity medications (AOMs) were used only by a very small proportion of individuals. Despite frequent weight loss attempts, most respondents did not achieve clinically meaningful weight loss.

Conclusions

Adults with OW or obesity experienced worse clinical, economic and HRQoL outcomes than those with NW. Better use of evidence-based obesity treatments, including prescription AOMs, should be considered to achieve more clinically meaningful weight reduction and improved outcomes in individuals with OW or obesity.

Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial

Importance

The effect of continued treatment with tirzepatide on maintaining initial weight reduction is unknown.

Objective

To assess the effect of tirzepatide, with diet and physical activity, on the maintenance of weight reduction.

Design, Setting, and Participants

This phase 3, randomized withdrawal clinical trial conducted at 70 sites in 4 countries with a 36-week, open-label tirzepatide lead-in period followed by a 52-week, double-blind, placebo-controlled period included adults with a body mass index greater than or equal to 30 or greater than or equal to 27 and a weight-related complication, excluding diabetes.

Interventions

Participants (n = 783) enrolled in an open-label lead-in period received once-weekly subcutaneous maximum tolerated dose (10 or 15 mg) of tirzepatide for 36 weeks. At week 36, a total of 670 participants were randomized (1:1) to continue receiving tirzepatide (n = 335) or switch to placebo (n = 335) for 52 weeks.

Main Outcomes and Measures

The primary end point was the mean percent change in weight from week 36 (randomization) to week 88. Key secondary end points included the proportion of participants at week 88 who maintained at least 80% of the weight loss during the lead-in period.

Results

Participants (n = 670; mean age, 48 years; 473 [71%] women; mean weight, 107.3 kg) who completed the 36-week lead-in period experienced a mean weight reduction of 20.9%. The mean percent weight change from week 36 to week 88 was -5.5% with tirzepatide vs 14.0% with placebo (difference, -19.4% [95% CI, -21.2% to -17.7%]; P < .001). Overall, 300 participants (89.5%) receiving tirzepatide at 88 weeks maintained at least 80% of the weight loss during the lead-in period compared with 16.6% receiving placebo (P < .001). The overall mean weight reduction from week 0 to 88 was 25.3% for tirzepatide and 9.9% for placebo. The most common adverse events were mostly mild to moderate gastrointestinal events, which occurred more commonly with tirzepatide vs placebo.

Conclusions and Relevance

In participants with obesity or overweight, withdrawing tirzepatide led to substantial regain of lost weight, whereas continued treatment maintained and augmented initial weight reduction.

Trial Registration

ClinicalTrials.gov Identifier: NCT04660643.

Tirzepatide reduces the predicted risk of atherosclerotic cardiovascular disease and improves cardiometabolic risk factors in adults with obesity or overweight: SURMOUNT-1 post hoc analysis

AIM

To assess the effect of tirzepatide on long-term risk of atherosclerotic cardiovascular disease (ASCVD) among people with obesity or overweight without diabetes from SURMOUNT-1.

MATERIALS AND METHODS

SURMOUNT-1, a phase 3 trial, evaluated the efficacy and safety of tirzepatide in adults with body mass index ≥30 or ≥27 kg/m2 and at least one weight-related complication, excluding diabetes. Participants were randomly assigned to tirzepatide (5/10/15 mg) or placebo. Changes from baseline in cardiometabolic variables were assessed. The predicted 10-year ASCVD risk scores were calculated (American College of Cardiology/American Heart Association risk engine) at baseline, week 24, and week 72 in SURMOUNT-1 participants without a history of ASCVD. Percent change in risk scores from baseline to weeks 24 and 72 was compared between tirzepatide and placebo using mixed model for repeated measures analysis. Analyses were also conducted in participants with intermediate to high risk at baseline.

RESULTS

Tirzepatide-treated groups demonstrated reductions in cardiometabolic variables over 72 weeks. In participants without a history of ASCVD (N = 2461), the baseline median risk score was low and did not differ across groups (1.5%-1.6%). Relative change in risk from baseline to week 72 was greater for tirzepatide (-23.5% to -16.4%) than placebo (12.7%; P < 0.001). Relative change among participants with intermediate-to-high baseline risk was significantly greater for tirzepatide (P < 0.05). Intermediate-to-high-risk participants demonstrated similar relative change but greater absolute risk reduction compared to the overall population.

CONCLUSION

Tirzepatide treatment significantly reduced the 10-year predicted risk of ASCVD versus placebo in patients with obesity or overweight without diabetes.

Tirzepatide reduces the predicted risk of developing type 2 diabetes in people with obesity or overweight: Post hoc analysis of the SURMOUNT-1 trial

AIM

We assessed the impact of tirzepatide on 10-year predicted risk of developing type 2 diabetes (T2D) among participants in the SURMOUNT-1 trial.

MATERIALS AND METHODS

In this post hoc analysis of SURMOUNT-1, the Cardiometabolic Disease Staging risk engine was used to calculate the 10-year predicted risk of T2D at baseline, week 24 and week 72 among participants randomized to receive 5, 10, or 15 mg tirzepatide or placebo. Mean changes in risk scores from baseline to weeks 24 and 72 were compared between tirzepatide and placebo groups. Subgroup analyses were conducted based on participants' glycaemic status and body mass index at baseline.

RESULTS

Mean baseline T2D predicted risk scores did not differ between tirzepatide and placebo groups (range: 22.9%-24.3%). At week 72, mean absolute T2D predicted risk score reductions were significantly greater in tirzepatide groups (5 mg, 12.4%; 10 mg, 14.4%; 15 mg, 14.7%) versus placebo (0.7%). At week 72, median relative predicted risk reductions following tirzepatide treatment ranged from 60.3% to 69.0%. For participants with and without prediabetes, risk reductions were significantly greater in tirzepatide groups versus placebo. At week 72, participants with prediabetes (range: 16.0%-20.3%) had greater mean risk score reductions from baseline versus those without prediabetes (range: 10.1%-11.3%). Across body mass index subgroups, mean reductions from baseline were significantly greater in tirzepatide groups versus placebo.

CONCLUSION

Tirzepatide treatment significantly reduced the 10-year predicted risk of developing T2D compared with placebo in participants with obesity or overweight, regardless of baseline glycaemic status.

Tirzepatide after intensive lifestyle intervention in adults with overweight or obesity: the SURMOUNT-3 phase 3 trial

The effects of tirzepatide, a glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, on weight reduction after successful intensive lifestyle intervention are unknown. This double-blind, placebo-controlled trial randomized (1:1) adults with body mass index ≥30 or ≥27 kg/m2 and at least one obesity-related complication (excluding diabetes), who achieved ≥5.0% weight reduction after a 12-week intensive lifestyle intervention, to tirzepatide maximum tolerated dose (10 or 15 mg) or placebo once weekly for 72 weeks (n = 579). The treatment regimen estimand assessed effects regardless of treatment adherence in the intention-to-treat population. The coprimary endpoint of additional mean per cent weight change from randomization to week 72 was met with changes of -18.4% (standard error (s.e.) 0.7) with tirzepatide and 2.5% (s.e. 1.0) with placebo (estimated treatment difference -20.8 percentage points (95% confidence interval (CI) -23.2%, -18.5%; P < 0.001). The coprimary endpoint of the percentage of participants achieving additional weight reduction ≥5% was met with 87.5% (s.e. 2.2) with tirzepatide and 16.5% (s.e. 3.0) with placebo achieving this threshold (odds ratio 34.6%; 95% CI 19.2%, 62.6%; P < 0.001). The most common adverse events with tirzepatide were gastrointestinal, with most being mild to moderate in severity. Tirzepatide provided substantial additional reduction in body weight in participants who had achieved ≥5.0% weight reduction with intensive lifestyle intervention. ClinicalTrials.gov registration: NCT04657016 .

Tirzepatide once weekly for the treatment of obesity in people with type 2 diabetes (SURMOUNT-2): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial

BACKGROUND

Weight reduction is essential for improving health outcomes in people with obesity and type 2 diabetes. We assessed the efficacy and safety of tirzepatide, a glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, versus placebo, for weight management in people living with obesity and type 2 diabetes.

METHODS

This phase 3, double-blind, randomised, placebo-controlled trial was conducted in seven countries. Adults (aged ≥18 years) with a body-mass index (BMI) of 27 kg/m2 or higher and glycated haemoglobin (HbA1c) of 7-10% (53-86 mmol/mol) were randomly assigned (1:1:1), using a computer-generated random sequence via a validated interactive web-response system, to receive either once-weekly, subcutaneous tirzepatide (10 mg or 15 mg) or placebo for 72 weeks. All participants, investigators, and the sponsor were masked to treatment assignment. Coprimary endpoints were the percent change in bodyweight from baseline and bodyweight reduction of 5% or higher. The treatment-regimen estimand assessed effects regardless of treatment discontinuation or initiation of antihyperglycaemic rescue therapy. Efficacy and safety endpoints were analysed with data from all randomly assigned participants (intention-to-treat population). This trial is registered with ClinicalTrials.gov, NCT04657003.

FINDINGS

Between March 29, 2021, and April 10, 2023, of 1514 adults assessed for eligibility, 938 (mean age 54·2 years [SD 10·6], 476 [51%] were female, 710 [76%] were White, and 561 [60%] were Hispanic or Latino) were randomly assigned and received at least one dose of tirzepatide 10 mg (n=312), tirzepatide 15 mg (n=311), or placebo (n=315). Baseline mean bodyweight was 100·7 kg (SD 21·1), BMI 36·1 kg/m2 (SD 6·6), and HbA1c 8·02% (SD 0·89; 64·1 mmol/mol [SD 9·7]). Least-squares mean change in bodyweight at week 72 with tirzepatide 10 mg and 15 mg was -12·8% (SE 0·6) and -14·7% (0·5), respectively, and -3·2% (0·5) with placebo, resulting in estimated treatment differences versus placebo of -9·6% percentage points (95% CI -11·1 to -8·1) with tirzepatide 10 mg and -11·6% percentage points (-13·0 to -10·1) with tirzepatide 15 mg (all p<0·0001). More participants treated with tirzepatide versus placebo met bodyweight reduction thresholds of 5% or higher (79-83% vs 32%). The most frequent adverse events with tirzepatide were gastrointestinal-related, including nausea, diarrhoea, and vomiting and were mostly mild to moderate in severity, with few events leading to treatment discontinuation (<5%). Serious adverse events were reported by 68 (7%) participants overall and two deaths occurred in the tirzepatide 10 mg group, but deaths were not considered to be related to the study treatment by the investigator.

INTERPRETATION

In this 72-week trial in adults living with obesity and type 2 diabetes, once-weekly tirzepatide 10 mg and 15 mg provided substantial and clinically meaningful reduction in bodyweight, with a safety profile that was similar to other incretin-based therapies for weight management.

FUNDING

Eli Lilly and Company.

Stratification of obesity phenotypes to optimize future therapy (SOPHIA)

INTRODUCTION

Obesity is considered a poor lifestyle choice. 'Obesity' is not a sufficient definition for patients, any more than 'cancer' or 'arthritis' would be. A major obstacle is the lack of understanding of pathogenesis. The disease of obesity is considered homogenous, while response to treatment is thought of as heterogeneous. This can change if pathogenesis, risk profiles for complications, and treatment responses are viewed within the context of obesity consisting of several subsets of disease.

AREAS COVERED

The European Union-funded Innovative Medicine Initiative project Stratification of Obesity Phenotypes to Optimize Future Obesity Therapy is part of a momentum shift. Operational variables are being used to develop tests and therapies which may allow the prediction of risk of obesities and the prediction of response to obesity treatments. However, changing stakeholder perspectives on obesity may require more than high-quality data and analysis.

EXPERT OPINION

For patients to benefit, clinicians need to integrate evidence-based treatments and payers need to reimburse the management of the disease of obesity. This will generate commercial opportunities for industry. We need to involve stakeholders (patients, clinicians, regulators, payer, patient organisations) to create a shared value for mutual gain.

General versus central adiposity as risk factors for cardiovascular-related outcomes in a high-risk population with type 2 diabetes: a post hoc analysis of the REWIND trial

BACKGROUND

In clinical practice, anthropometric measures other than BMI are rarely assessed yet may be more predictive of cardiovascular (CV) risk. We analyzed the placebo group of the REWIND CV Outcomes Trial to compare several anthropometric measures as baseline risk factors for cardiovascular disease (CVD)-related outcomes in participants with type 2 diabetes (T2D).

METHODS

Data from the REWIND trial placebo group (N = 4952) were analyzed. All participants had T2D, age ≥ 50 years, had either a previous CV event or CV risk factors, and a BMI of ≥ 23 kg/m². Cox proportional hazard models were used to investigate if BMI, waist-to-hip ratio (WHR), and waist circumference (WC) were significant risk factors for major adverse CV events (MACE)-3, CVD-related mortality, all-cause mortality, and heart failure (HF) requiring hospitalization. Models were adjusted for age, sex, and additional baseline factors selected by LASSO method. Results are presented for one standard deviation increase of the respective anthropometric factor.

RESULTS

Participants in the placebo group experienced 663 MACE-3 events, 346 CVD-related deaths, 592 all-cause deaths, and 226 events of HF requiring hospitalization during the median follow-up of 5.4 years. WHR and WC, but not BMI, were identified as independent risk factors of MACE-3 (hazard ratio [HR] for WHR: 1.11 [95% CI 1.03 to 1.21]; p = 0.009; HR for WC: 1.12 [95% CI 1.02 to 1.22]; p = 0.012). WC adjusted for hip circumference (HC) showed the strongest association with MACE-3 compared to WHR, WC, or BMI unadjusted for each other (HR: 1.26 [95% CI 1.09 to 1.46]; p = 0.002). Results for CVD-related mortality and all-cause mortality were similar. WC and BMI were risk factors for HF requiring hospitalization, but not WHR or WC adjusted for HC (HR for WC: 1.34 [95% CI 1.16 to 1.54]; p < 0.001; HR for BMI: 1.33 [95% CI 1.17 to 1.50]; p < 0.001). No significant interaction with sex was observed.

CONCLUSIONS

In this post hoc analysis of the REWIND placebo group, WHR, WC and/or WC adjusted for HC were risk factors for MACE-3, CVD-related mortality, and all-cause mortality; while BMI was only a risk factor for HF requiring hospitalization. These findings indicate the need for anthropometric measures that consider body fat distribution when assessing CV risk.

Tirzepatide for the treatment of obesity: Rationale and design of the SURMOUNT clinical development program

OBJECTIVE

Obesity is a growing global concern compounded by limited availability of effective treatment options. The SURMOUNT development program aims to evaluate the efficacy and safety of tirzepatide as an adjunct to lifestyle intervention compared with placebo on chronic weight management in adults with BMI ≥ 27 kg/m² with or without type 2 diabetes.

METHODS

The SURMOUNT program includes four global phase 3 trials NCT04184622 (SURMOUNT-1), NCT04657003 (SURMOUNT-2), NCT04657016 (SURMOUNT-3), and NCT04660643 (SURMOUNT-4). Participants are randomized to once-weekly subcutaneous tirzepatide versus placebo in a double-blind manner. The primary end point in all trials is the percentage change in body weight from randomization to end of treatment. Results for the primary end point for SURMOUNT-1 were published recently and results for the other trials are expected in 2023.

RESULTS

Across trials, participants have a mean age of 44.9 to 54.2 years, are mostly female (50.7% to 69.7%), and have a mean BMI of 36.1 to 38.9.

CONCLUSIONS

The extensive assessment of once-weekly tirzepatide in the global SURMOUNT program will detail the clinical effects of this first-in-class glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist in chronic weight management.

A qualitative study to examine meaningful change in physical function associated with weight-loss

PURPOSE

This study explored perceptions of meaningful weight-loss and the level of change on two patient-reported outcome (PRO) measures, the 36-item Short Form Health Survey® [SF-36v2®] and Impact of Weight on Quality of Life Lite-Clinical Trials^© [IWQOL-Lite-CT^©], that individuals living with overweight or obesity consider to be meaningful and indicative of treatment success.

METHODS

Thirty-three qualitative interviews were conducted in the US with adults living with overweight or obesity. Concept elicitation explored perceptions of minimally important/meaningful weight-loss using open-ended questions. Cognitive debriefing was used to understand thresholds for meaningful change on both measures.

RESULTS

Most participants (n = 23/33) expected a 5% total body weight-loss to yield some benefit in physical functioning, while all participants expected a 10% weight-loss to provide a meaningful and noticeable improvement in their physical functioning. Participants indicated that an item-level 1-point score change on each measure would represent a noticeable improvement in physical functioning and indicate treatment success.

CONCLUSIONS

Participants expected moderate weight-losses to be noticeable, with ≥ 10% weight-loss yielding the most consistent results. The findings suggested that both measures provide strong opportunity to demonstrate treatment benefit in relation to physical functioning as a small change on the response scale would represent a noticeable improvement in participants' daily lives.

Tirzepatide Once Weekly for the Treatment of Obesity

BACKGROUND

Obesity is a chronic disease that results in substantial global morbidity and mortality. The efficacy and safety of tirzepatide, a novel glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, in people with obesity are not known.

METHODS

In this phase 3 double-blind, randomized, controlled trial, we assigned 2539 adults with a body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) of 30 or more, or 27 or more and at least one weight-related complication, excluding diabetes, in a 1:1:1:1 ratio to receive once-weekly, subcutaneous tirzepatide (5 mg, 10 mg, or 15 mg) or placebo for 72 weeks, including a 20-week dose-escalation period. Coprimary end points were the percentage change in weight from baseline and a weight reduction of 5% or more. The treatment-regimen estimand assessed effects regardless of treatment discontinuation in the intention-to-treat population.

RESULTS

At baseline, the mean body weight was 104.8 kg, the mean BMI was 38.0, and 94.5% of participants had a BMI of 30 or higher. The mean percentage change in weight at week 72 was -15.0% (95% confidence interval [CI], -15.9 to -14.2) with 5-mg weekly doses of tirzepatide, -19.5% (95% CI, -20.4 to -18.5) with 10-mg doses, and -20.9% (95% CI, -21.8 to -19.9) with 15-mg doses and -3.1% (95% CI, -4.3 to -1.9) with placebo (P<0.001 for all comparisons with placebo). The percentage of participants who had weight reduction of 5% or more was 85% (95% CI, 82 to 89), 89% (95% CI, 86 to 92), and 91% (95% CI, 88 to 94) with 5 mg, 10 mg, and 15 mg of tirzepatide, respectively, and 35% (95% CI, 30 to 39) with placebo; 50% (95% CI, 46 to 54) and 57% (95% CI, 53 to 61) of participants in the 10-mg and 15-mg groups had a reduction in body weight of 20% or more, as compared with 3% (95% CI, 1 to 5) in the placebo group (P<0.001 for all comparisons with placebo). Improvements in all prespecified cardiometabolic measures were observed with tirzepatide. The most common adverse events with tirzepatide were gastrointestinal, and most were mild to moderate in severity, occurring primarily during dose escalation. Adverse events caused treatment discontinuation in 4.3%, 7.1%, 6.2%, and 2.6% of participants receiving 5-mg, 10-mg, and 15-mg tirzepatide doses and placebo, respectively.

CONCLUSIONS

In this 72-week trial in participants with obesity, 5 mg, 10 mg, or 15 mg of tirzepatide once weekly provided substantial and sustained reductions in body weight. (Supported by Eli Lilly; SURMOUNT-1 ClinicalTrials.gov number, NCT04184622.).

Tirzepatide Once Weekly for the Treatment of Obesity

BACKGROUND

Obesity is a chronic disease that results in substantial global morbidity and mortality. The efficacy and safety of tirzepatide, a novel glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, in people with obesity are not known.

METHODS

In this phase 3 double-blind, randomized, controlled trial, we assigned 2539 adults with a body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) of 30 or more, or 27 or more and at least one weight-related complication, excluding diabetes, in a 1:1:1:1 ratio to receive once-weekly, subcutaneous tirzepatide (5 mg, 10 mg, or 15 mg) or placebo for 72 weeks, including a 20-week dose-escalation period. Coprimary end points were the percentage change in weight from baseline and a weight reduction of 5% or more. The treatment-regimen estimand assessed effects regardless of treatment discontinuation in the intention-to-treat population.

RESULTS

At baseline, the mean body weight was 104.8 kg, the mean BMI was 38.0, and 94.5% of participants had a BMI of 30 or higher. The mean percentage change in weight at week 72 was -15.0% (95% confidence interval [CI], -15.9 to -14.2) with 5-mg weekly doses of tirzepatide, -19.5% (95% CI, -20.4 to -18.5) with 10-mg doses, and -20.9% (95% CI, -21.8 to -19.9) with 15-mg doses and -3.1% (95% CI, -4.3 to -1.9) with placebo (P<0.001 for all comparisons with placebo). The percentage of participants who had weight reduction of 5% or more was 85% (95% CI, 82 to 89), 89% (95% CI, 86 to 92), and 91% (95% CI, 88 to 94) with 5 mg, 10 mg, and 15 mg of tirzepatide, respectively, and 35% (95% CI, 30 to 39) with placebo; 50% (95% CI, 46 to 54) and 57% (95% CI, 53 to 61) of participants in the 10-mg and 15-mg groups had a reduction in body weight of 20% or more, as compared with 3% (95% CI, 1 to 5) in the placebo group (P<0.001 for all comparisons with placebo). Improvements in all prespecified cardiometabolic measures were observed with tirzepatide. The most common adverse events with tirzepatide were gastrointestinal, and most were mild to moderate in severity, occurring primarily during dose escalation. Adverse events caused treatment discontinuation in 4.3%, 7.1%, 6.2%, and 2.6% of participants receiving 5-mg, 10-mg, and 15-mg tirzepatide doses and placebo, respectively.

CONCLUSIONS

In this 72-week trial in participants with obesity, 5 mg, 10 mg, or 15 mg of tirzepatide once weekly provided substantial and sustained reductions in body weight. (Supported by Eli Lilly; SURMOUNT-1 ClinicalTrials.gov number, NCT04184622.).

Clinical outcomes associated with anti-obesity medications in real-world practice: A systematic literature review

Anti-obesity medications (AOMs) are efficacious and well tolerated in randomized controlled trials, but findings may not be generalizable to routine clinical practice. This systematic literature review aimed to identify real-world (RW) evidence for AOMs to treat adults ( ≥ 18 years) with obesity or overweight (BMI  ≥  27 kg/m² ). Searches conducted in MEDLINE, Embase, Health Technology Assessment (HTA) Database, National Health Service (NHS) Economic Evaluation Database, and Cochrane Central Register of Controlled Trials for studies of relevant FDA-approved AOMs yielded 41 publications. Weight loss (WL) was consistently observed, with 14% to 58.6% of patients achieving ≥ 5% WL on orlistat, phentermine/topiramate, naltrexone/bupropion, phentermine, or liraglutide in studies of 3-6 months' duration where this was measured. When cardiometabolic risk factors were assessed, AOMs reduced or had no impact on blood pressure, lipids, or glycemia. RW data on the impact of AOMs on existing obesity-related comorbidities and mortality were generally lacking. AOMs were associated with various adverse events, but these were of mild to moderate severity and no unexpected safety signals were reported. A pattern of poor adherence and persistence with AOMs was observed across studies. Overall, the review confirmed the effectiveness of AOMs in RW settings but demonstrated large gaps in the evidence base.

Anti-obesity Medication Use Among Adults with Overweight and Obesity in the United States: 2015-2018

OBJECTIVE

To estimate utilization of FDA-approved prescription anti-obesity medications (AOMs) and identify factors associated with AOM use in the United States.

METHODS

Respondents >18 years-old meeting AOM eligibility criteria in 2015-2016 and 2017-2018 National Health and Nutrition Examination Survey (NHANES) and 2016 Medical Expenditure Panel Survey (MEPS) were included in the study. AOM eligibility was defined as having a body mass index (BMI) >30 kg/m², or a BMI between 27 to 29.9 kg/m² and at least one obesity-related comorbidity. Demographic, socioeconomic, and clinical characteristics, economic outcomes and health-related quality of life were summarized and compared between AOM users and non-users. Multivariable logistic regression was used to identify factors associated with AOM use.

RESULTS

Only 0.80% of eligible adults reported use of AOMs in the past 30 days in 2015-2016 and 2017-2018 NHANES. A greater proportion of current AOM users previously tried dietary changes compared to non-users. They also reported an average weight loss of 6.8 lbs. (3.1 kg) over the previous year compared to a 3.3 lbs. (1.5 kg) gain among non-users. Total healthcare costs trended higher among AOM users, driven mostly by higher outpatient healthcare costs. A BMI ≥30 kg/m², depression, dyslipidemia, and infertility predicted AOM use, whereas Medicare and being at risk of sleep apnea were associated with lower odds of AOM use.

CONCLUSION

Despite availability of newer AOMs and inclusion of AOMs in medical treatment guidelines, AOM utilization remains low. This may reflect under-prescribing of and/or restricted patient access to approved evidence-based pharmacotherapy for obesity.

Clinical Management of Obesity in Women: Addressing a Lifecycle of Risk

The World Health Organization estimates that nearly 2 billion people worldwide are overweight, 600 million of whom are obese. The increasing prevalence of this condition in women is of particular concern given its impact on reproductive health and mortality. Burgeoning data implicating maternal obesity in fetal programming and the metabolic health of future generations further suggest that obesity in women is one of the most pressing public health concerns of the twenty-first century. However, health care professionals are infrequently engaged in obesity management. This article provides a conceptual understanding of obesity and a rational approach to treatment.

Weight Loss After RYGB Is Independent of and Complementary to Serotonin 2C Receptor Signaling in Male Mice

Roux-en-Y gastric bypass (RYGB) typically leads to substantial, long-term weight loss (WL) and diabetes remission, although there is a wide variation in response to RYGB among individual patients. Defining the pathways through which RYGB works should aid in the development of less invasive anti-obesity treatments, whereas identifying weight-regulatory pathways unengaged by RYGB could facilitate the development of therapies that complement the beneficial effects of surgery. Activation of serotonin 2C receptors (5-HT2CR) by serotonergic drugs causes WL in humans and animal models. 5-HT2CR are located on neurons that activate the melanocortin-4 receptors, which are essential for WL after RYGB. We therefore sought to determine whether 5-HT2CR signaling is also essential for metabolic effects of RYGB or whether it is a potentially complementary pathway, the activation of which could extend the benefits of RYGB. Diet-induced obese male mice deficient for the 5-HT2CR and their wild-type littermates underwent RYGB or sham operation. Both groups lost similar amounts of weight after RYGB, demonstrating that the improved metabolic phenotype after RYGB is 5-HT2CR independent. Consistent with this hypothesis, wild-type RYGB-treated mice lost additional weight after the administration of the serotonergic drugs fenfluramine and meta-chlorophenylpiperazine but not the nonserotonergic agent topiramate. The fact that RYGB does not depend on 5-HT2CR signaling suggests that there are important WL mechanisms not fully engaged by surgery that could potentially be harnessed for medical treatment. These results suggest a rational basis for designing medical-surgical combination therapies to optimize clinical outcomes by exploiting complementary physiological mechanisms of action.

Complications of Video-Assisted Thoracoscopic Lung Biopsy in Patients with Interstitial Lung Disease

BACKGROUND

Current guidelines recommend surgical lung biopsy for diagnosis of interstitial lung diseases (ILDs) in selected patients. To shed light on the risk-benefit ratio for this recommendation, we examined the morbidity and mortality associated with video-assisted thoracoscopic surgical (VATS) lung biopsy in a group of outpatients.

METHODS

A retrospective cohort study was conducted of 68 consecutive ambulatory patients with radiographically apparent interstitial lung disease (ILD) referred for VATS biopsy during a 6-year period. Incidence of postoperative mortality, prolonged air leaks, pneumonias, and re-admissions were calculated. Risk factors for complications of surgery were examined.

RESULTS

Three deaths occurred within 60 days after biopsy for a mortality rate of 4.4% (95% confidence interval [CI], 1% to 12%), and 19.1% (95% CI, 11% to 31%) experienced one or more complications of surgery. Risk factors for morbidity included preoperative dependence on oxygen therapy and pulmonary hypertension. The three patients who died had usual interstitial pneumonia on their biopsy specimen and were reintubated postoperatively for acute lung injury. Aggregation of articles published over the past 10 years reporting on surgical lung biopsy for the diagnosis of ILD yielded a postoperative mortality rate of 2% to 4.5%.

CONCLUSIONS

VATS lung biopsy for diagnosis of ILD, even in ambulatory patients, is not an entirely benign procedure. Biopsy rarely may trigger an acute exacerbation of usual interstitial pneumonitis. The risk of postoperative complications appears to be greatest in those dependent on oxygen and those who have pulmonary hypertension. This information may be used in weighing the risk-benefit ratio of biopsy in individual patients.

A possible hot spot in exon 21 of the retinoblastoma gene predisposing to a low penetrant retinoblastoma phenotype?

PURPOSE

To identify the mutation in the RB1 gene in a Syrian family showing incomplete penetrance of retinoblastoma (RB).

METHODS

Genomic DNA was used as a template for the PCR reaction to amplify all exons as well as the promoter region of RB1 gene. These PCR products were screened by conformational sensitive gel electrophoresis and the 331-bp product containing exon 21 showing anomalous migration was sequenced directly to identify the mutation.

RESULTS

We identified the missense point mutation in exon 21 of the RB1 gene converting a Cys-->Arg (codon 712) in one family with a low penetrant phenotype. The proband was unilaterally affected, whereas the paternal uncle was bilaterally affected and the mutation carrier father was unaffected. The T-->C substitution abolished a cleavage site for the Nde I restriction enzyme, enabling rapid detection of the mutant allele.

CONCLUSION

Phenotypically, this family is different from the previously described low penetrant phenotype pedigree with the same mutation whose affected members all had unilateral tumors. These results suggest that codon 712 may represent a mutational 'hot spot' for the low penetrant phenotypes and that the mutation codes for retinoblastoma protein with an apparently residual tumor-suppressive function give rise to low penetrance. These results also raise the interesting question: what other factors influence the phenotype of mutation carriers in addition to the predisposing missense mutation.

Molecular analysis of the retinoblastoma (RB1) gene in acute myeloid leukemia patients

The pathogenesis of acute leukemia is still poorly understood. In the past few years several groups have reported deletion of the RB1 gene or altered pRB expression in certain hematologic malignancies, suggesting a possible role of RB1 gene inactivation in the process of leukemogenesis. Most studies regarding structural abnormalities of the RB1 gene indicate that gross deletions or rearrangements are present in a small percentage of patients with acute myeloid leukemia (AML), as is the case with retinoblastoma, where the majority of RB1 gene abnormalities are attributed to point mutations. To investigate if such point mutations in the RB1 gene may have a role in leukemogenesis in AML, we screened the RB1 gene of 36 AML patients using conformation-sensitive gel electrophoresis (CSGE). No point mutations were found in the 27 exons, their flanking intron regions or in the promoter region in any of the 36 patients. Thus, according to our findings, the susceptibility in these patients for developing AML does not appear to be related to point mutations in the RB1 gene. While screening for point mutations, we identified a number of new and previously noted neutral sequence variations indicating the efficiency and sensitivity of CSGE in identifying small changes in the RB1 gene.

PCR assay confirms diagnosis in syndrome with variably expressed phenotype: mutation detection in Stickler syndrome

Stickler syndrome is an autosomal dominant disease with ocular (severe myopia, vitreal degeneration, and retinal detachment) and other systemic manifestations (hearing loss, cleft palate, epiphyseal dysplasia, and premature osteoarthritis). As with other dominantly inherited conditions, the clinical phenotype of Stickler syndrome varies considerably. To date, all mutations have been located in the type II procollagen (COL2A1) gene. Analysis of a C-->T mutation we had identified previously, in COL2A1 gene in exon 40, in a three generation pedigree showed the loss of a cleavage site for the TaqI restriction enzyme. We designed a rapid PCR based restriction enzyme assay to detect this mutation and used it to establish the diagnosis in a neonate from the same pedigree, presenting with the first occurrence of the Pierre-Robin sequence in the family and minimal ocular findings. These results underline the potential diagnostic value of many as yet undetected DNA mutations in families affected with Stickler syndrome, since the variability of the phenotype can impede accurate diagnosis, appropriate genetic counselling, and effective intervention and prophylactic treatment for affected people.

Stickler syndrome. A mutation in the nonhelical 3' end of type II procollagen gene

BACKGROUND

All of the mutations in the type II procollagen (COL2A1) gene that have been identified in families affected with Stickler syndrome have been located primarily in the triple helical region of the gene. We report what we believe is the first premature stop codon in the globular C-propeptide region encoded by the COL2A1 gene, in a family affected with Stickler syndrome.

DESIGN

Genomic DNA from affected and unaffected family members of this three-generation family was amplified using the polymerase chain reaction. The polymerase chain reaction products were directly sequenced for DNA analysis.

RESULTS

Direct sequencing showed a single base deletion in exon 50, resulting in a premature stop codon in exon 51 in the globular C-propeptide of COL2A1 gene in all affected members.

CONCLUSIONS

These results implicate premature stop codons as a common cause of Stickler syndrome. The location of this premature stop codon in the far end of the nonhelical 3' end of the gene indicates that a truncated C-propeptide of at least 84 amino acid residues is inadequate for the functional gene product.

Modification of standard proteinase K/phenol method for DNA isolation to improve yield and purity from frozen blood

Research in medical genetics may frequently involve freezing of large numbers of peripheral blood samples. This is a convenient method for storing blood for subsequent DNA isolation and analysis. An area of potential concern is the low yield of DNA from blood samples that have been frozen. Here we report a modification of the widely used standard proteinase K/phenol DNA isolation method for improving the yield and purity of DNA from frozen blood samples, by an initial trypsinisation of whole blood before cell lysis to obtain lymphocytic nuclei and subsequent DNA purification. We report an increased total yield of DNA with pretrypsinised blood as well as improved purity. These results indicate that trypsinisation of thawed whole blood helps the deproteinisation process, reducing the amount of protein associated with the nuclear pellet. This modification to improve yield and purity of DNA from frozen blood samples should be useful to laboratories performing DNA based diagnostic work or studying molecular genetic mechanisms of disease.

Identification and rapid screening of a DraI RFLP by PCR in the retinoblastoma gene

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A second mutation in the type II procollagen gene (COL2AI) causing stickler syndrome (arthro-ophthalmopathy) is also a premature termination codon

Genetic linkage analyses suggest that mutations in type II collagen may be responsible for Stickler syndrome, or arthro-ophthalmopathy (AO), in many families. In the present study oligonucleotide primers were developed to amplify and directly sequence eight of the first nine exons of the gene for type II procollagen (COL2A1). Analysis of the eight exons in 10 unrelated probands with AO revealed that one had a single-base mutation in one allele that changed the codon of -CGA- for arginine at amino acid position alpha 1-9 in exon 7 to a premature termination signal for translation. The second mutation found to cause AO was, therefore, similar to the first in that both created premature termination signals in the COL2A1 gene. Since mutations producing premature termination signals have not previously been detected in genes for fibrillar collagens, the results raise the possibility that such mutations in the COL2A1 gene are a common cause of AO.

Detection of sequence variants in the gene for human type II procollagen (COL2A1) by direct sequencing of polymerase chain reaction-amplified genomic DNA

The direct sequencing of the human type II procollagen (COL2A1) gene from polymerase chain reaction (PCR)-amplified genomic DNA is described. Thirty-two regions of the COL2A1 gene were asymmetrically amplified with intron primers which were specifically chosen to amplify a region spanning 500 to 800 bp of sequence encoding one or more exons and their accompanying intervening sequences. Primers for dideoxynucleotide sequencing of the PCR products were then designed to provide complete exon sequence information and to insure that intron:exon splice junction sequence data would be obtained. Amplification and sequencing reactions were performed on an automated workstation to facilitate the handling of multiple DNA templates. The procedure allowed efficient sequencing of over 25,000 bp of each allele of the COL2A1 gene per diploid genome. We used this method for the comparative analyses of COL2A1 sequences in DNA isolated from the blood of 42 unrelated individuals and we identified 21 neutral sequence variants in the gene. The sequence variations were confirmed by independent assays, including restriction enzyme digestion. The sequence variants described here will be important for identifying haplotypes of the type II procollagen gene that will be useful in defining a genetic etiology for diseases of cartilaginous tissues.

Stop codon in the procollagen II gene (COL2A1) in a family with the Stickler syndrome (arthro-ophthalmopathy)

Linkage analysis with restriction fragment length polymorphisms for the gene for type II procollagen (COL2A1) was carried out in a family with the Stickler syndrome, or arthro-ophthalmopathy, an autosomal dominant disorder that affects the eyes, ears, joints, and skeleton. The analysis demonstrated linkage of the disease and COL2A1 with a logarithm-of-odds score of 1.51 at zero recombination. A newly developed procedure for preparing cosmid clones was employed to isolate the allele for type II procollagen that was linked to the disease. Analysis of over 7000 nucleotides of the gene revealed a single base mutation that altered a CG dinucleotide and converted the codon CGA for arginine at amino acid position alpha 1-732 to TGA, a stop codon. From previous work on procollagen biosynthesis, it is apparent that the truncated polypeptide synthesized from an allele with a stop codon at alpha 1-732 cannot participate in the assembly of type II procollagen, and therefore that the mutation would decrease synthesis of type II procollagen. It was not apparent, however, why the mutation produced marked changes in the eye, which contains only small amounts of type II collagen, but relatively mild effects on the many cartilaginous structures of the body that are rich in the same protein.