Obesity care can make a big difference, but few get it, study suggests

When someone has obesity, losing even 5% of their body weight can make a major difference in their health -- especially if they can keep from regaining it.

Now, a new study in tens of thousands of people with obesity shows the impact of different weight management treatments in achieving this goal.

For those who received one of these treatments -- nutrition counseling, medically supervised meal replacements, any anti-obesity medications or bariatric surgery -- the odds of losing 5% of their body weight or more in just a year ranged from nearly 1 in 4 to nearly surefire, depending on the treatment.

But the study also suggests that most people with obesity aren’t getting weight-related care from their usual source of health care. The study team, from Michigan Medicine, the University of Michigan’s academic medical center, report their findings in JAMA Network Open.

The team behind the study hopes their findings will inspire more primary care clinics, health systems and insurers to increase the number of people with obesity who get help in choosing, starting and staying on a treatment that works for them. Members of the research team have spent the past few years building and testing a program to do just that for patients receiving primary care through U-M Health.

Underuse of widely available treatments

Effective weight management treatment doesn’t necessarily require using one of the GLP-1 medicines such as semaglutide or tirzepatide that are often in short supply and not covered by insurance. In fact, the study involved data from the years just before any such drugs received FDA approval for treating obesity.

Rather, the study points to the power of offering patients a range of options that are all supported by medical evidence, from nutrition counseling and medication to meal replacement and bariatric surgery.

Both at the individual and population level, receiving one of these under a provider’s guidance was much more likely to lead to a weight loss of 5% or more, compared with anything patients with obesity might have done on their own, the study shows.

“These findings suggest that all weight management treatment options can be highly effective. The challenge is helping individual patients find a treatment that works for them and that they can stick with over time,” said Dina Hafez Griauzde, M.D., M.Sc., senior author of the new study and a certified obesity medicine specialist. She is an assistant professor of internal medicine at the U-M Medical School, and a primary care physician and co-director of the weight management program at VA Ann Arbor Healthcare System.

The anonymous data for the study came from all patients with obesity who went to a primary care provider at any of U-M’s clinics in the five years before the COVID-19 pandemic. In all, only 5% of the patients in this population who had a body-mass index of 30 or more received one of the evaluated weight management treatment options in 2017; that rose to about 7% in 2019.

Lead author James Henderson, Ph.D., a research scientist in the Department of Internal Medicine who led the detailed statistical modeling and analysis of the patient data, notes that the study focuses not just on individuals but also on populations.

The percentage of people in the study population who qualified for a diagnosis of obesity rose during the study period. Without weight management treatments people with obesity in this population were equally likely to gain at least 5% of their baseline weight as to achieve at least a 5% weight loss, effectively  “cancelling out” on the population level.

“Our model shows that even doubling the currently small percentage of patients receiving weight management treatment from their care team could tip the balance at the population level, counteracting the overall trend toward weight gain,” said Henderson.

More about the study

Of the nearly 54,000 patients with obesity in the study, nearly 49,000 did not have any record of working with a U-M provider to try any of the weight management therapies that the study looked at.

The team matched data from each of the 5,090 patients who did receive weight management treatment from their U-M team with data from a patient who was similar in many ways, including BMI, but did not receive such care at U-M. Then they tracked weight changes over time.

Nutrition counseling was the most common treatment used, with 3,364 patients having at least one appointment with a registered dietitian. Only 189 patients had at least one visit for a meal replacement program, 520 went through bariatric surgery, and 1,428 took any form of anti-obesity medication.

Medications considered as a group for the study were orlistat (available as a generic drug or under the names Xenical and Alli), liraglutide (sold as Victoza or Saxenda), drug combinations involving naltrexone and buproprion (Contrave), or phentermine and topiramate (Qsymia), and also GLP-1 medications approved for diabetes management at the time of the study.

After a year, the team calculated that those who didn’t use a WMT under the supervision of a U-M provider would have about a 1 in 6 chance of losing 5% of their body weight or more.

By contrast, those who received nutrition counseling would have greater than a 1 in 5 chance of losing 5% or more. The probability of losing at least this much weight by taking an anti-obesity medication was a little higher, greater than a 1 in 4 chance.

If someone were able to stick with medically prescribed meal replacement for a year – not an easy task for many people -- they would have a 1 in 2 chance of losing 5% of their weight. And those who choose bariatric surgery would have a 9 in 10 chance of losing at least 5% of their weight and an 8 in 10 chance of losing at least 10%.

Navigating weight management in a new way

In the past two years, U-M Health has enhanced its broad effort to increase weight management care. It recognizes the complex nature of obesity, which research at U-M and other major centers has shown to be shaped by genetics, life experiences, the food environment, physical and mental health conditions, and more.

U-M’s primary care-based program is called the Weight Navigation Program. Griauzde serves as research director, working with its medical director, endocrinologist Andrew Kraftson, M.D. The WNP works in collaboration with primary care physicians and other providers, who may not have time during regular appointments, or specialized training, to handle all aspects of weight management treatment.

Patients in the program see a primary care physician who is board-certified in obesity medicine, to learn about and choose a treatment path tailored to their needs. Then, through ongoing support -- including regular check-ins via text messaging -- their progress is tracked, and their treatment plan adapted as needed if they don’t respond to the initial chosen treatment.

The program is supported by the Departments of Family Medicine and Internal Medicine, including the Divisions of General Medicine and Metabolism, Endocrinology and Diabetes, and the Elizabeth Weiser Caswell Diabetes Institute. In addition to working with individual patients, the program harnesses data science to track its performance, and is preparing to publish the first findings about its impact.

The program also partners with researchers across U-M who are running weight-related studies, such as diet and lifestyle studies based in the School of Nursing and a two-year structured Weight Management Program.

In addition to Henderson, Griauzde and Kraftson, the new study’s authors are Anne P. Ehlers, MD, MPH; Joyce M. Lee, MD, MPH; Kenneth Piehl, BS; and Caroline R. Richardson, MD. Griauzde, Henderson, Ehlers and Lee are members of the U-M Institute for Healthcare Policy and Innovation, whose Data and Methods Hub team worked with the researchers. Richardson, a former faculty member in Family Medicine and member of IHPI, is now at Brown University.

The study was funded by multiple grants from the National Institute of Diabetes and Digestive and Kidney Diseases, part of the National Institutes of Health (DK123416, DK092926, DK089503, DK020572, DK092926), including funding for the Michigan Center for Diabetes Translational Research and the Michigan Nutrition Obesity Research Center.

Weight Loss Treatment and Longitudinal Weight Change Among Primary Care Patients With Obesity, JAMA Network Open, doi:10.1001/jamanetworkopen.2023.56183