Research shows that people who stop using the Mujaro shot for weight loss are not only prone to regaining weight, but also to a decline in other health indicators.
Mujaro, which contains the active ingredient tirzepatide, has become a popular weight loss medicine. Research shows it can help people lose weight. on average 20% of body weight after 72 weeks of treatment.
However, previous studies have shown that people who stop taking tirzepatide tend to regain most of the lost weight.
Now experts reviewing the results of the clinical trial, known as Surmount-4, say other benefits seen with the drug, such as lower blood pressure and bad cholesterol levels, are also reversed when the shots are stopped.
Naveed Sattar, professor of cardiometabolic medicine at the University of Glasgow, who was not part of the team but was involved in previous work on the study, said “the results are not a surprise as excess weight is a well-recognized cause of high blood pressure and poor glucose control.”
He added: “Consequently, when weight lost through therapeutic interventions is regained, these cardiometabolic risk factors typically increase in proportion to the rate and extent of weight regain.
“Sustainable weight management remains a critical challenge, but it is hoped that new, more accessible strategies will emerge in the coming years to support long-term weight maintenance.”
Research also suggested using tirzepatide and other weight-loss drugs for people with heart disease reduce the risk of hospitalization for heart failure or death from any cause. “So stopping them could eliminate the protective effect,” Sattar said.
Article in the journal Jama Internal Medicine. The researchers, who included experts from the pharmaceutical company that makes Mounjaro, Eli Lilly, describe how they analyzed data from the Surmount-4 study, a study involving obese or overweight participants with at least one weight-related health problem.
All participants received tirzepatide for 36 weeks along with diet and exercise, and were then randomized into two equally sized groups, one of which continued taking the drug for an additional 52 weeks, and the other switched to placebo during this period. Both participants and researchers did not know who was in which group at the time.
The team focused on the results of 308 participants who had lost at least 10% of their weight by the end of the initial 36-week period before switching to placebo, finding that one year after stopping tirzepatide, 82% of these participants had regained 25% or more of their initial weight loss.
The team found that greater weight gain at the end of the study was associated with greater rebound improvements not only in weight, but also in measures such as waist circumference, bad cholesterol, blood pressure and blood glucose levels.
“Overall, at week 88, participants with 75% or more weight recovery after tirzepatide discontinuation had their cardiometabolic parameters returned to baseline values (week 0),” the team wrote, although they note that participants with up to 50% weight recovery still experienced improvements in these areas compared to the start of the study.
The team says the results “support the importance of long-term weight loss maintenance through lifestyle changes and anti-obesity medications to maintain cardiometabolic benefits and improve health-related quality of life.”
Jane Ogden, Professor Emeritus of the School Health Scientists from the University of Surrey added that taking weight-loss drugs does not always lead to healthier eating and exercise habits, noting that it can sometimes lead to poorer diets as people lose motivation to eat well and prepare meals.
“After stopping the medication, people experience weight gain as they return to their previous behavior. This can lead to changes in cardiovascular health as their diet and exercise return to what they were before,” she said.
Another study shows that women who stop using weight-loss drugs such as tirzepatide or semaglutide before pregnancy or early in pregnancy tend to gain more weight during pregnancy and have a higher risk of preterm birth, gestational diabetes, and hypertensive disorders during pregnancy than those who did not use such drugs.
However, Sattar warned that latest study does not prove cause and effect, and said further testing is needed.
“Women receiving [weight-loss jabs] would likely have become pregnant at a lower weight than they otherwise would have, and this difference in weight is extremely difficult to fully explain in an observational analysis,” he said. “Therefore, the results should be interpreted with caution.”
