Risk of colorectal cancer after initiation of orlistat: matched cohort study

Osmanthus fragrans Flavonoid Extract Inhibits Adipogenesis and Induces Beiging in 3T3-L1 Adipocytes

Osmanthus fragrans has a long history of cultivation in Asia and is widely used in food production for its unique aroma, which has important cultural and economic values. It is rich in flavonoids with diverse pharmacological properties, such as antioxidant, anti-tumor, and anti-lipid activities. However, little is known regarding the effects of Osmanthus fragrans flavonoid extract (OFFE) on adipogenesis and pre-adipocyte transdifferentiation. Herein, this research aimed to investigate the effect of OFFE on the differentiation, adipogenesis, and beiging of 3T3-L1 adipocytes and to elucidate the underlying mechanism. Results showed that OFFE inhibited adipogenesis, reduced intracellular reactive oxygen species levels in mature adipocytes, and promoted mitochondrial biogenesis as well as beiging/browning in 3T3-L1 adipocytes. This effect was accompanied by increased mRNA and protein levels of the brown adipose-specific marker gene Pgc-1a, and the upregulation of the expression of UCP1, Cox7A1, and Cox8B. Moreover, the research observed a dose-dependent reduction in the mRNA expression of adipogenic genes (C/EBPα, GLUT-4, SREBP-1C, and FASN) with increasing concentrations of OFFE. Additionally, OFFE activated the AMPK signaling pathway to inhibit adipogenesis. These findings elucidate that OFFE has an inhibitory effect on adipogenesis and promotes browning in 3T3-L1 adipocytes, which lays the foundation for further investigation of the lipid-lowering mechanism of OFFE in vivo in the future.

Weight Loss Induced by Antiobesity Medications and All-Cause Mortality Among Patients With Knee or Hip Osteoarthritis

OBJECTIVE

The current guidelines recommend weight loss for patients with overweight or obesity and knee or hip osteoarthritis (OA); however, there is a paucity of data on the relation of weight loss to death among patients with OA. We aimed to examine the relation of the rate of weight loss induced by antiobesity medications over one year to all-cause mortality among patients with overweight or obesity and knee or hip OA.

METHODS

Using the IQVIA Medical Research Database, we identified people with overweight or obesity and knee or hip OA. We emulated analyses of a hypothetical target trial to assess the effect of slow-to-moderate (2%-10%) or fast (≥10%) weight loss induced by the initiation of antiobesity medications within one year on all-cause mortality and secondary outcomes over five years' follow-up.

RESULTS

Among 6,524 participants, the five-year all-cause mortality rates were 5.3%, 4.0%, and 5.4% for weight gain or stable, slow-to-moderate weight loss, and fast weight loss arms, respectively. Compared with the weight gain or stable arm, hazard ratios of all-cause mortality were 0.72 (95% confidence interval [CI] 0.56-0.92) for the slow-to-moderate weight loss arm and 0.99 (95% CI 0.67-1.44) for the fast weight loss arm. We found dose-response protective effects of weight loss on incident hypertension, type 2 diabetes, and venous thromboembolism but a slightly higher risk of cardiovascular disease, albeit not statistically significant, in the fast rate of weight loss arm than in the weight gain or stable arm and no significant relations of weight loss to the risk of cancer.

CONCLUSION

In this population-based study, a slow-to-moderate, but not fast, rate of weight loss induced by antiobesity medications is associated with a lower risk of all-cause mortality in people with overweight or obesity and knee or hip OA.

Use of weight loss medications in relation with prostate, colorectal and male breast cancers among older men: SEER-Medicare 2007-2015

BACKGROUND

The association of weight loss medications with prostate (PCa), colorectal (CRC) or male breast cancers, including assessment of these cancers combined (HRCs, hormone-associated cancers) remain poorly understood. Testosterone replacement therapy (TTh) is reported to be inversely associated with obesity, PCa and CRC, but it is unclear whether TTh modifies the association of weight loss medications with HRCs.

METHODS

In 49,038 men (≥ 65 years) of SEER-Medicare, we identified 15,471 men diagnosed with PCa, 4836 with CRC, and 141 with male breast cancers. Pre-diagnostic prescription of weight loss medications and TTh was ascertained for this analysis. Weighted multivariable-adjusted conditional logistic and Cox proportional hazards (mortality) models were conducted.

RESULTS

We found an inverse association between use of weight loss medications and incident PCa (OR 0.59, 95% CI 0.57-0.62), CRC (OR 0.86, 95% CI 0.80-0.92), and HRCs (OR 0.65, 95% CI 0.62-0.68). Similar associations were observed for advanced stage at diagnosis of PCa and CRC. Effects of weight loss medications on PCa and HRC remained significant irrespective of the use of TTh but were only suggestive with CRC with positive TTh use. No associations were observed with male breast cancer and HRCs mortality.

CONCLUSION

Pre-diagnostic use of weight loss medications reduced the incidence of PCa, CRC, and HRCs. These associations persisted in the same direction irrespective of the history of TTh use. Future studies are needed to confirm these findings and to identify underlying biological mechanisms of weight loss medications and TTh on the risk of cancer.

Metabolic and bariatric surgery and obesity pharmacotherapy for cancer prevention: current status and future possibilities

Obesity is a chronic, relapsing, progressive disease of excess adiposity that increases the risk of developing at least 13 types of cancer. This report provides a concise review of the current state of the science regarding metabolic and bariatric surgery and obesity pharmacotherapy related to cancer risk. Meta-analyses of cohort studies report that metabolic and bariatric surgery is independently associated with a lower risk of incident cancer than nonsurgical obesity care. Less is known regarding the cancer-preventive effects of obesity pharmacotherapy. The recent approval and promising pipeline of obesity drugs will provide the opportunity to understand the potential for obesity therapy to emerge as an evidence-based cancer prevention strategy. There are myriad research opportunities to advance our understanding of how metabolic and bariatric surgery and obesity pharmacotherapy may be used for cancer prevention.

Obesity and multiple myeloma: emerging mechanisms and perspectives

Obesity is a global pandemic that has been associated with the development of breast, endometrial, large intestine, renal, esophageal, and pancreatic cancer. Obesity is also involved in the development of cardiovascular disease and type 2 diabetes mellitus. Recently, an increase in the incidence of obesity-related cancers has been reported. Multiple myeloma (MM) is the second most common hematological malignancy, after lymphoma. The aim of this review is to examine the epidemiological data on obesity and MM, assess the effect of obesity on MM outcomes, evaluate the possible mechanisms through which obesity might increase the incidence of MM and provide the effects of obesity management on MM. Current evidence indicates that obesity may have an impact on the progression of monoclonal gammopathy of undetermined significance (MGUS) to MM and increase the prevalence of MM. However, data regarding the effect of obesity on MGUS incidence are controversial; further studies are needed to examine whether obesity affects the development of MGUS or the progression of MGUS to MM. In addition, obesity affects MM outcomes. Increased BMI is associated with decreased survival in patients with MM, while data regarding the effect of obesity on newly diagnosed MM subjects and autologous stem cell transplantation are limited. Interestingly, the obesity paradox may also apply to patients with relapsed/refractory MM who are overweight or obese, because they may have a survival advantage. The pathophysiological pathways linking obesity to MM are very complicated and include bone marrow adipose tissue; adipokines, such as adiponectin, leptin, resistin, and visfatin; inflammatory cytokines and growth factors, such as TNF-α and IL-6; hormones including insulin and the insulin-like growth factor system as well as sex hormones. In terms of the effect of pharmacological management of obesity, orlistat has been shown to alter the proliferation of MM cells, whereas no data exist on glucagon-like peptide-1 receptor agonists, naltrexone/bupropion, or phentermine/topiramate. Bariatric surgery may be associated with a reduction in the incidence of MM, however, further studies are needed.

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 Drug Orlistat Alleviates Western-Diet-Driven Colitis-Associated Colon Cancer via Inhibition of STAT3 and NF-κB-Mediated Signaling

Many researchers have argued that Western diet (WD)-induced obesity accelerates inflammation and that inflammation is a link between obesity and colorectal cancer (CRC). This study investigated the effect of WDs on the development and progression of colitis-associated colon cancer (CAC) and the efficacy of the anti-obesity agent orlistat on WD-driven CAC in mice. The results revealed that the WD exacerbated CAC in azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mice, which showed increased mortality, tumor formation, and aggravation of tumor progression. Furthermore, WD feeding also upregulated inflammation, hyperplasia, and tumorigenicity levels through the activation of STAT3 and NF-κB signaling in an AOM/DSS-induced mouse model. In contrast, treatment with orlistat increased the survival rate and alleviated the symptoms of CAC, including a recovery in colon length and tumor production decreases in WD-driven AOM/DSS-induced mice. Additionally, orlistat inhibited the extent of inflammation, hyperplasia, and tumor progression via the inhibition of STAT3 and NF-κB activation. Treatment with orlistat also suppressed the β-catenin, slug, XIAP, Cdk4, cyclin D, and Bcl-2 protein levels in WD-driven AOM/DSS-induced mice. The results of this study indicate that orlistat alleviates colon cancer promotion in WD-driven CAC mice by suppressing inflammation, especially by inhibiting STAT3 and NF-κB activation.

Lipid metabolism in cancer: New perspectives and emerging mechanisms

Tumors undergo metabolic transformations to sustain uncontrolled proliferation, avoid cell death, and seed in secondary organs. An increased focus on cancer lipid metabolism has unveiled a number of mechanisms that promote tumor growth and survival, many of which are independent of classical cellular bioenergetics. These mechanisms include modulation of ferroptotic-mediated cell death, support during tumor metastasis, and interactions with the cells of the tumor microenvironment. As such, targeting lipid metabolism for anti-cancer therapies is attractive, with recent work on small-molecule inhibitors identifying compounds to target lipid metabolism. Here, we discuss these topics and identify open questions.

Long-Term Efficacy and Safety of Anti-Obesity Treatment: Where Do We Stand?

PURPOSE OF REVIEW

As a chronic and relapsing disease, obesity impairs metabolism and causes cardiovascular diseases. Although behavioral modification is important for the treatment of obesity, it is difficult to achieve an ideal weight or sustain the process of long-term weight loss. Therefore, the obesity control guidelines strongly recommend lifestyle interventions along with medical treatment for patients who are overweight. There is sufficient evidence supporting that pharmacotherapy in combination with behavior-based interventions can result in significant weight loss and improved cardiometabolism.

RECENT FINDINGS

Recent meta-analyses of new anti-obesity drugs and their weight-loss efficacy have shown that the overall placebo-subtracted weight reduction (%) for at least 12 months ranged from 2.9 to 6.8% for the following drugs: phentermine/topiramate (6.8%), liraglutide (5.4%), naltrexone/bupropion (4.0%), orlistat (2.9%), and lorcaserin (3.1%). However, very recently, on February 13, 2020, the US Food and Drug Administration (FDA) ordered the withdrawal of lorcaserin from markets, as a clinical trial to assess drug safety showed an increased risk of cancer. Currently, the anti-obesity medications that have been approved by the FDA for chronic weight management are orlistat, phentermine/topiramate, naltrexone/bupropion, and liraglutide. However, they are costly and may have adverse effects in some individuals. Therefore, drug therapy should be initiated in obese individuals after weighing its benefits and risks. One of the strategies for long-term obesity control is that anti-obesity medications should be tailored for specific patients depending on their chronic conditions, comorbidities, and preferences.

Obstetrician-Gynecologists' Strategies for Patient Initiation and Maintenance of Antiobesity Treatment with Glucagon-Like Peptide-1 Receptor Agonists

Obesity is a chronic disease affecting women at higher rates than men. In an obstetrics and gynecology setting, frequently encountered obesity-related complications are polycystic ovary syndrome, fertility and pregnancy complications, and increased risk of breast and gynecological cancers. Obstetrician-gynecologists (OBGYNs) are uniquely positioned to diagnose and treat obesity, given their role in women's primary health care and the increasing prevalence of obesity-related fertility and pregnancy complications. The metabolic processes of bodyweight regulation are complex, which makes weight-loss maintenance challenging, despite dietary modifications and exercise. Antiobesity medications (AOMs) can facilitate weight loss by targeting appetite regulation. There are four AOMs currently approved for long-term use in the United States, of which liraglutide 3.0 mg is among the most efficacious. Liraglutide 3.0 mg, a glucagon-like peptide-1 receptor agonist (GLP-1 RA), is superior to placebo in achieving weight loss and improving cardiometabolic profile, in both clinical trial and real-world settings. In addition, women with fertility complications receiving liraglutide 1.8–3.0 mg can benefit from improved ovarian function and fertility. Liraglutide 3.0 mg is generally well tolerated, but associated with transient gastrointestinal side effects, which can be mitigated. In this review, we present the risks of obesity and benefits of weight loss for women, and summarize clinical development of GLP-1 RAs for weight management. Finally, we provide practical advice and recommendations for OBGYNs to open the discussion about bodyweight with their patients, initiate lifestyle modification and GLP-1 RA treatment, and help them persist with these interventions to achieve optimal weight loss with associated health benefits.

Anti-Obesity Drugs: Long-Term Efficacy and Safety: An Updated Review

As a chronic and relapsing disease, obesity negatively impacts the health of men to a greater extent than that of women, with a higher risk of cardiovascular disease. Since lifestyle modifications alone are often challenging and limited for the maintenance of weight reduction, pharmacotherapy should be considered in a timely manner for obese men or overweight patients with weight-related comorbidities. Recent advances in anti-obesity drugs have enabled the potential of achieving clinically significant weight loss. Increasing evidence has shown that behavior-based interventions with one of these medications can result in greater weight loss than that elicited by usual care conditions. Data from most recent meta-analyses showed that the overall placebo-subtracted weight reduction (%) with the use of anti-obesity drugs for at least 12 months ranges from 2.9% to 6.8%; phentermine/topiramate (−6.8%) liraglutide (−5.4%), naltrexone/bupropion (−4.0%), lorcaserin (−3.1%), and orlistat (−2.9%). However, they have a high cost and may cause adverse outcomes depending on the individual. Very recently, on February 13, 2020, the US Food and Drug Administration requested withdrawal of lorcaserin from the market because a safety clinical trial showed an increased occurrence of cancer. Therefore the decision to initiate drug therapy in obese individuals should be made after the benefits and risks are considered. Thereafter, treatment should be tailored to specific patient subpopulations depending on their chronic conditions, comorbidities, and preferences. Herein, we provide an overview of the latest developments in weight loss medications, which may serve as one of the strategies for long-term obesity control.

Behavioral and Pharmacotherapy Weight Loss Interventions to Prevent Obesity-Related Morbidity and Mortality in Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Overweight and obesity have been associated with adverse health effects.

OBJECTIVE

To systematically review evidence on benefits and harms of behavioral and pharmacotherapy weight loss and weight loss maintenance interventions in adults to inform the US Preventive Services Task Force.

DATA SOURCES

MEDLINE, PubMed Publisher-Supplied Records, PsycINFO, and the Cochrane Central Register of Controlled Trials for studies published through June 6, 2017; ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials through August 2017; and ongoing surveillance in targeted publications through March 23, 2018. Studies from previous reviews were reevaluated for inclusion.

STUDY SELECTION

Randomized clinical trials (RCTs) focusing on weight loss or weight loss maintenance in adults.

DATA EXTRACTION AND SYNTHESIS

Data were abstracted by one reviewer and confirmed by another. Random-effects meta-analyses were conducted for weight loss outcomes in behavior-based interventions.

MAIN OUTCOMES AND MEASURES

Health outcomes, weight loss or weight loss maintenance, reduction in obesity-related conditions, and adverse events.

RESULTS

A total of 122 RCTs (N = 62 533) and 2 observational studies (N = 209 993) were identified. Compared with controls, participants in behavior-based interventions had greater mean weight loss at 12 to 18 months (-2.39 kg [95% CI, -2.86 to -1.93]; 67 studies [n = 22065]) and less weight regain (-1.59 kg [95% CI, -2.38 to -0.79]; 8 studies [n = 1408]). Studies of medication-based weight loss and maintenance interventions also reported greater weight loss or less weight regain in intervention compared with placebo groups at 12 to 18 months (range, -0.6 to -5.8 kg; no meta-analysis). Participants with prediabetes in weight loss interventions had a lower risk of developing diabetes compared with controls (relative risk, 0.67 [95% CI, 0.51 to 0.89]). There was no evidence of other benefits, but most health outcomes such as mortality, cardiovascular disease, and cancer were infrequently reported. Small improvements in quality of life in some medication trials were noted but were of unclear clinical significance. There was no evidence of harm such as cardiovascular disease from behavior-based interventions; higher rates of adverse events were associated with higher dropout rates in medication groups than in placebo groups.

CONCLUSIONS AND RELEVANCE

Behavior-based weight loss interventions with or without weight loss medications were associated with more weight loss and a lower risk of developing diabetes than control conditions. Weight loss medications, but not behavior-based interventions, were associated with higher rates of harms. Long-term weight and health outcomes data, as well as data on important subgroups, were limited.

Safety and tolerability of new-generation anti-obesity medications: a narrative review

The prevalence of obesity and associated comorbidities is rising. Despite their weight-loss efficacy, new generation anti-obesity medications are only prescribed to a minority of adults with obesity, possibly, which in part may be due to safety concerns. This review presents detailed safety profiles for orlistat, phentermine/topiramate, lorcaserin, naltrexone/bupropion and liraglutide 3.0 mg, and discusses the associated risk-benefit profiles. Two anti-obesity medications presented safety issues that warranted further discussion; phentermine/topiramate (fetal toxicity) and liraglutide 3.0 mg (risk of gallstone disease and mild, acute pancreatitis), whereas the adverse events associated with orlistat, lorcaserin, and naltrexone/bupropion were mostly transient tolerability issues. The difficulties surrounding the objective determination of risk-benefit for anti-obesity medications is discussed. The need for more long-term data, thorough patient assessment, individualization of pharmacological interventions and adherence to stopping rules to maximize risk-benefit are highlighted. Overall, the majority of new generation anti-obesity medications present encouraging tolerability profiles; however, in some cases a lack of long-term clinical trials confounds the accurate determination of risk-benefit.

Risk of breast cancer among patients with bioprosthetic or mechanical valve replacement: a population-based study in Sweden

The association between breast cancer and warfarin is inconclusive as most previous studies examined their association using patients with thromboembolism, whereas thromboembolism itself is a risk factor for cancer. We explored this issue using patients received mechanical heart valves replacement as a proxy for warfarin exposure as these patients need a lifelong warfarin treatment, and compared them with patients received bioprosthesis valves replacement (short-term warfarin treatment) in Sweden between 1987 and 2010. Patients who were operated on for valve replacement were identified from the Swedish Hospital Discharge Registry and linked to the Swedish Cancer Registry to examine the hazard ratios of subsequent breast cancer. A total of 12,242 women were operated on for valve replacement (5481 with mechanical valve and 6401 with bioprosthetic valve). For the entire cohort, the HR of breast cancer was 1.49 (95 % CI 1.09-2.02) among patients with mechanical valve replacement compared to those with bioprosthetic valve replacement. After controlling for a number of confounding factors using propensity score weighting, the HR was 1.69 (95 % CI 1.15-2.47). Our study found that patients with mechanical valve replacement have an increased risk of breast cancer compared to those with bioprosthetic valve replacement. If confirmed, this increased risk should be considered when recommending breast cancer screening for women with mechanical valve replacement. Long-term use of warfarin may explain the observed increase. If so, patients who have used warfarin long-term for other reasons should be studied for a possible increased risk of breast cancer.

Terminating observation within matched pairs of subjects in a matched cohort analysis: a Monte Carlo simulation study

Matched cohort analyses are becoming increasingly popular for estimating treatment effects in observational studies. However, in the applied biomedical literature, analysts and authors are inconsistent regarding whether to terminate follow-up among members of a matched set once one member is no longer under observation. This paper focused on time-to-event outcomes and used Monte Carlo simulation methods to determine the optimal approach. We found that the bias of the estimated treatment effect estimate was negligible under both approaches and that the percentage of censoring had no discernible effect on the magnitude of bias. The mean model-based standard error of the treatment estimate was consistently higher when we terminated observation within matched pairs. Furthermore, the type 1 error rate was consistently lower when we did not terminate follow-up within matched pairs. In conclusion, when the focus was on time-to-event outcomes, we demonstrated that there was no advantage to terminating follow-up within matched pairs. Continuing follow-up on each subject until their observation was naturally complete was superior compared with terminating a subject's observation time once its matched pair had ceased to be under observation. Given the frequency with which these analyses are conducted in the applied literature, our results provide important guidance to analysts and applied researchers as to the preferred analytic approach.

Misclassification in administrative claims data: quantifying the impact on treatment effect estimates

Misclassification is present in nearly every epidemiologic study, yet is rarely quantified in analysis in favor of a focus on random error. In this review, we discuss past and present wisdom on misclassification and what measures should be taken to quantify this influential bias, with a focus on bias in pharmacoepidemiologic studies. To date, pharmacoepidemiology primarily utilizes data obtained from administrative claims, a rich source of prescription data but susceptible to bias from unobservable factors including medication sample use, medications filled but not taken, health conditions that are not reported in the administrative billing data, and inadequate capture of confounders. Due to the increasing focus on comparative effectiveness research, we provide a discussion of misclassification in the context of an active comparator, including a demonstration of treatment effects biased away from the null in the presence of nondifferential misclassification. Finally, we highlight recently developed methods to quantify bias and offer these methods as potential options for strengthening the validity and quantifying uncertainty of results obtained from pharmacoepidemiologic research.

Misclassification in administrative claims data: quantifying the impact on treatment effect estimates

Misclassification is present in nearly every epidemiologic study, yet is rarely quantified in analysis in favor of a focus on random error. In this review, we discuss past and present wisdom on misclassification and what measures should be taken to quantify this influential bias, with a focus on bias in pharmacoepidemiologic studies. To date, pharmacoepidemiology primarily utilizes data obtained from administrative claims, a rich source of prescription data but susceptible to bias from unobservable factors including medication sample use, medications filled but not taken, health conditions that are not reported in the administrative billing data, and inadequate capture of confounders. Due to the increasing focus on comparative effectiveness research, we provide a discussion of misclassification in the context of an active comparator, including a demonstration of treatment effects biased away from the null in the presence of nondifferential misclassification. Finally, we highlight recently developed methods to quantify bias and offer these methods as potential options for strengthening the validity and quantifying uncertainty of results obtained from pharmacoepidemiologic research.