Obesity and type 2 diabetes are risk factors for various malignancies, including pancreatic cancer, which has a high death rate. A new analysis in Diabetes/Metabolism Research and Reviews suggests that metabolic-bariatric surgery may lower the risk of developing pancreatic cancer in people with obesity, especially in those who also have type 2 diabetes.
In the systematic review and meta-analysis, investigators identified 12 relevant studies that explored the effects of metabolic-bariatric surgery on pancreatic cancer incidence, with a total of 3 711 243 adults with obesity. Surgery was associated with a 44% reduction in pancreatic cancer risk among individuals with obesity but without type 2 diabetes and a 79% risk reduction in those with both obesity and type 2 diabetes.
“Metabolic-bariatric surgery not only has beneficial effects on obesity and type 2 diabetes but also may play a crucial role in reducing the risk of pancreatic cancer in these individuals,” said corresponding author Angeliki M. Angelidi, PhD, of the Broad Institute of MIT and Harvard. “These findings underscore the need for further research to elucidate the underlying mechanisms and understand the full spectrum of health benefits of metabolic-bariatric surgery beyond weight loss.”
Compared to antihypertensives alone, bariatric surgery is more effective in controlling hypertension rates in people with obesity and uncontrolled hypertension, according to a study published in the Journal of the American College of Cardiology. People who underwent bariatric surgery had lower BMI and were on fewer medications after five years while maintaining normal blood pressure levels than those who only used antihypertensive medications.
“In clinical practice, obesity is an overlooked condition. As a consequence, there is a frequent failure in approaching obesity as a crucial step for mitigating the risk of important cardiovascular risk factors including hypertension,” said Carlos Aurelio Schiavon, MD, FACS, lead author of the study and a surgeon specialising in bariatric surgery at Heart Hospital (hcor) and BP Hospital in Sao Paulo.
Researchers in this study looked at the impact of treating obesity to lower hypertension. While new weight loss drugs exist, long-term adherence to medication can be challenging.
This study looks at bariatric surgery as a better long-term solution to control obesity and, as a result, hypertension.
The GATEWAY trial included 100 people (76% of whom were female) who had a body mass index (BMI) of around 36.9kg/m2. All participants had hypertension and were using at least two medications. People with previous cardiovascular events and poorly controlled Type 2 diabetes were excluded.
Subjects were assigned to either Roux-en-Y gastric bypass with medical therapy or medial therapy alone and the primary outcome was reduction of at least 30% antihypertensive medications while maintaining blood pressure levels less than 140/90mmHg at five years.
At five years, BMI was 28.01kg/m2 for those who received bariatric surgery and 36.40kg/m2 for those on medical therapy alone.
People who had bariatric surgery had an 80.7% reduction in the number of medications they were taking compared to a 13.7% reduction in those only using medical therapy.
Hypertension remission, defined as controlled blood pressure without medications, was 46.9% in those who underwent bariatric surgery compared to 2.4% in those on medical therapy alone.
“Our results underscore the importance of approaching obesity in reducing hypertension rates,” Schiavon said.
Limitations of the study include that it was a single-center, open-label study with a small sample size and there was loss of follow up in some patients.
In an accompanying editorial comment, Michael Hall, MD, MSc, professor and chair of the Department of Medicine at the University of Mississippi Medical Center, said the study provides important long-term data on the benefits of gastric bypass on weight loss and blood pressure control, but questions remain.
“Further studies assessing the threshold for bariatric surgery in people with obesity, optimal timing of bariatric surgery in obese people with cardiometabolic diseases, type of bariatric surgery and comparative studies of obesity pharmacotherapies and bariatric surgery are needed to clarify the optimal treatment pathways for this common and growing disease,” he said.
The two most common obesity surgeries, gastric bypass and gastric sleeve, have few short-term complications and show no significant differences, according to study findings published in the journal JAMA Network Open. These are the first results of a multicentre randomised controlled trial comparing obesity surgeries conducted by the University of Gothenburg.
Patients undergoing obesity surgery will normally have a BMI of at least 40, or 35 if they also have other serious medical conditions related to obesity.
The most common procedures are gastric bypass, where a large part of the stomach and part of the small intestine are bypassed, and gastric sleeve, where a large part of the stomach is surgically removed.
The aim of the current study was to compare the short-term risks of the different procedures.
The study is the largest of its kind. 1735 adult patients planned for surgery in Norway and Sweden between 2015 and 2022 agreed to participate, and they were randomly assigned to either gastric bypass or gastric sleeve.
Relatively few complications
Surgical time was longer for gastric bypass, averaging 68 minutes compared to 47 minutes for gastric sleeve, but hospitalisation after surgery was one day regardless of method.
The follow-ups also gave equivalent results for the two methods.
At 30 days after surgery, both groups had relatively few complications such as haemorrhage, leakage, blood clots and infections.
No deaths occurred during the follow-up period of a total of 90 days.
“For both surgical procedures, the risk of complications is very low, especially from an international perspective, and there is no statistically significant or clinically relevant difference between the groups,” says Suzanne Hedberg, first author of the study.
Many stakeholders and many opinions
“Many people have had surgery, or are on waiting lists for surgery, and there are lots of discussions and opinions about the different methods. What the study shows is that patients and doctors can now choose their surgical method without considering short-term surgical risks,” she says.
Suzanne Hedberg defended her thesis in surgery at Sahlgrenska Academy, University of Gothenburg in April 2023, and is a consultant at Sahlgrenska University Hospital.
The study, included in her thesis, is the first publication with results from BEST (Bypass Equipoise Sleeve Trial), a Scandinavian registry-based randomised controlled multicentre study comparing the two methods of obesity surgery.
The main outcome of the trial which analyses the risk of complications and weight progression over 5 years, is expected to be completed in 2028.
“For the ongoing studies, we are off to a good start with equivalent groups, laying a good foundation for further comparisons of more long-term results,” concludes Suzanne Hedberg.
Young people who have had surgery for obesity do not improve their mental health despite significant and permanent weight loss. At the same time, bariatric surgery also increases the risk of early alcohol problems. This is according to the largest long-term study of young people who have undergone bariatric surgery, the results of which were published in Lancet Child and Adolescent Health.
The researchers studied mental health problems – before and after surgery – among all young people in Sweden who underwent bariatric surgery between 2007 and 2017. The study was conducted using register data, which enabled the scope of the study and facilitated comparisons with other groups in society.
The study recruited 1554 adolescents (< 21 years) with severe obesity underwent bariatric surgery between 2007 and 2017, 1169 (75%) of whom were female. At time of surgery, the mean age was 19·0 years [SD 1·0], and the mean BMI was 43·7 kg/m2 (SD 5·5). They were matched with 15 540 adolescents from the general population.
It was found that young people who underwent surgery were more likely to have received treatment and medication for mental health problems already five years before the surgery.
“Although mental illness generally increases between the ages of 15 and 21, for this group the need for treatment increased faster than for young people in general”, says Kajsa Järvholm, Associate Professor of Psychology at Lund University.
Unfortunately, this pattern continued even after obesity surgery; the young people who had the surgery continued to have a greater need for mental health treatment than their peers.
“Obesity surgery has very positive effects on weight, blood sugar and blood pressure control, but when it comes to mental health, it does not get better or worse after bariatric surgery”, says Martin Neovius, Professor of Clinical Epidemiology at Karolinska Institutet.
Additional findings from the new study include an increase in dependency diagnoses, particularly on alcohol, in the surgical group, both in comparison to pre-surgery and to young people in general.
The study is the largest long-term study in the world of young people who have had obesity surgery.
A study of obese adults with nonalcoholic fatty liver disease (NAFLD) and morbid obesity has shown that those who underwent bariatric surgery suffered far fewer extreme cardiovascular events subsequently.
Reporting their results in JAMA Network Open, the researchers, reported that these obese patients (BMI > 40) undergoing bariatric surgery had a 49% lower risk of developing adverse cardiovascular events.
“The findings provide evidence in support of bariatric surgery as an effective therapeutic tool to lower elevated risk of cardiovascular disease for select individuals with obesity and NAFLD,” said Vinod K. Rustgi, profesor at Rutgers Robert Wood Johnson Medical School. “These finding are tremendously impactful for many reasons.”
NAFLD, and a more advanced form known as NASH, are rapidly increasing causes of liver disease which occur because of excessive fat storage in the liver. As such it is common in obesity and type 2 diabetes.
In the study, researchers analysed outcomes data, using a medical insurance database, from 2007 to 2017. Of 230 million covered individuals, 86 964 adults between the ages of 18 and 64 who had obesity and NAFLD were identified. Of those, 68% were female, 35% underwent bariatric surgery and 65% received nonsurgical care.
Bariatric surgery patients experienced a 49% decrease in the risk of developing major cardiovascular events such as heart attacks, heart failure or ischemic strokes. They were also far less likely to experience angina, atherosclerotic events or arterial blood clots.
The association between bariatric surgery and risk reduction of developing cardiovascular disease has not been studied to this level of detail before, the researchers said.
There is growing evidence that bariatric surgery, because of the weight reduction it brings about in patients, offers definitive health benefits. A study conducted by Rustgi and colleagues, published in the journal Gastroenterology in March 2021, showed that bariatric surgery can also significantly reduce the risk of cancer, especially obesity-related, in obese individuals with NAFLD. Importantly, these cancers included colorectal, pancreatic, endometrial, thyroid cancer, multiple myeloma and hepatocellular carcinoma.
“Although bariatric surgery is a more aggressive approach than lifestyle modifications, it may be associated with other benefits, such as improved quality of life and decreased long-term health care burden,” Rustgi said.
A study published in JAMA shows that weight loss through bariatric surgery for adults with obesity was associated with a 32% lower risk of developing cancer and a 48% lower risk of cancer-related death compared with those who did not have the surgery.
Rising obesity numbers are being seen all over the world. The International Agency for Research on Cancer describes 13 types of cancer as obesity-associated cancers such as endometrial cancer, postmenopausal breast cancer, and cancers of the colon, liver, pancreas, ovary and thyroid.
Lead author of the study, Ali Aminian, MD, at Cleveland Clinic, said that bariatric surgery is currently the most effective treatment for obesity. “Patients can lose 20 to 40% of their body weight after surgery, and weight loss can be sustained over decades. The striking findings of this study indicate that the greater the weight loss, the lower the risk of cancer,” said Dr Aminian.
From 2004 and 2017, the SPLENDID (Surgical Procedures and Long-term Effectiveness in Neoplastic Disease Incidence and Death) study matched a group of 5053 adult patients with obesity who had bariatric surgery 1:5 to a control group of 25 265 patients with obesity who did not undergo the surgery.
After 10 years, 2.9% of patients in the bariatric surgery group and 4.9% of patients in the non-surgical group developed an obesity-associated cancer.
After 10 years, 0.8% of patients in the surgery group and 1.4% of patients in the non-surgical group died from cancer, indicating that bariatric surgery is associated with a 48% lower cancer mortality risk.
Researchers noted that the benefits of bariatric surgery were seen in a wide range of study participants in terms of age, sex and race. In addition, benefits were similarly observed after both gastric bypass and gastric sleeve operations.
“According to the American Cancer Society, obesity is second only to tobacco as a preventable cause of cancer in the United States,” said the study’s senior author, Steven Nissen, MD, Chief Academic Officer of the Heart, Vascular and Thoracic Institute. “This study provides the best possible evidence on the value of intentional weight loss to reduce cancer risk and mortality.”
Numerous studies have shown the health benefits of bariatric or weight-loss surgery in patients with obesity. The Cleveland Clinic-led STAMPEDE study showed that following bariatric surgery, significant weight loss and control of type 2 diabetes last over time. The SPLENDOR study showed that in patients with fatty liver, bariatric surgery decreases the risk of the progression of liver disease and serious heart complications.
The SPLENDID study adds important findings to the literature focused on the link between obesity and cancer. Given the growing epidemic of obesity worldwide, these findings have considerable public health implications.
“Based on the magnitude of benefit shown in our study, weight loss surgery can be considered in addition to other interventions that can help prevent cancer and reduce mortality,” said Jame Abraham, M.D., chairman of the Hematology and Medical Oncology Department at Cleveland Clinic. “Further research needs to be done to understand the underlying mechanisms responsible for reduced cancer risk following bariatric surgery.”
