Obesity is a known driver behind over 200 chronic health conditions. A common belief is that individuals dealing with multiple health issues struggle to shed as much weight as those without complications.

In a recent study, scientists aimed to assess whether a greater number of obesity-linked health conditions would hinder the overall potential for weight loss.

The study revealed that the presence of obesity-related conditions does not impact the overall weight reduction achieved when using the anti-obesity medication Zepbound (tirzepatide).

This study, funded by Eli Lilly, the producer of tirzepatide, was presented at the Endocrine Society's ENDO 2024 conference in Boston, MA on June 1. These results, however, have yet to undergo publication in a peer-reviewed journal.

Zepbound shows effectiveness across diverse health conditions

In the study, researchers observed that treatment with tirzepatide facilitated significant weight reduction in patients, regardless of the number of concurrent obesity-related medical conditions present at the start of the research.

The team examined data spanning four clinical trials, which, while differing in design and participant profiles, encompassed 4,726 individuals either dealing with obesity (BMI over 30) or being overweight (BMI 27 or above) alongside an obesity-related medical condition. Among these participants, 938 were from a trial involving type 2 diabetes.

Researchers organized weight loss outcomes within the tirzepatide groups by categorizing participants according to their number of obesity-related conditions (none, one, or two or more) and compared these outcomes with those receiving a placebo.

Older participants or individuals with a lengthier history of obesity tended to show more medical complications related to obesity, as expected.

Nevertheless, those treated with tirzepatide exhibited more pronounced weight loss compared to those on placebo, irrespective of other obesity-driven conditions.

Lead researcher Dr. Sriram Machineni, an associate professor of Medicine at the Albert Einstein College of Medicine, stated in an interview with Medical News Today:

“Weight loss driven by Tirzepatide is comparable in patients dealing with a range of medical issues, including hypertension, sleep apnea, or liver disease, when compared to patients whose only concern is obesity itself.”

Echoing these sentiments, Dr. Mir Ali, a bariatric surgeon at the Memorial Care Surgical Weight Loss Center in Fountain Valley, CA, who was not involved in the study, commented to MNT: “This research aligns with what we’ve observed from our surgical weight loss procedures.”

“What stands out is that weight loss occurs independently of co-existing medical complications. In fact, the reduction in weight further improves other issues. This study also underscores that newer medications provide superior results when compared to earlier treatments.”

— Mir Ali, MD, bariatric surgeon

Tirzepatide: A new innovation in weight management

In November 2023, Tirzepatide received FDA approval for chronic weight management.

Marketed under the brand name Zepbound, this medication is advised for managing chronic weight in adults with obesity or those overweight alongside at least one obesity-related condition, like type 2 diabetes, high blood pressure, or elevated cholesterol.

Tirzepatide is administered as a once-weekly injection under the skin, effectively lowering blood sugar while promoting weight loss more efficiently than older treatments.

Common side effects include nausea, diarrhea, and vomiting, although these tend to lessen as treatment progresses.

Belonging to a new class of diabetes treatments, tirzepatide functions as a dual agonist of glucose-dependent insulinotropic polypeptide (GIP) and GLP-1 receptors. These are hormones released by the intestines in response to food intake.

Incretin hormones induce the pancreas’ beta cells to release insulin. GLP-1, in particular, enhances insulin production, curtails glucagon levels (to avoid excessive drops in blood sugar), increases beta cell size and number, and fosters a sense of fullness by slowing gastric emptying. It also plays a role in regulating appetite through the central nervous system.

GIP, similarly, stimulates insulin production, encourages beta cell growth while reducing their destruction, lowers fat accumulation, boosts bone formation, enhances glucagon secretion, and reduces stomach acid levels.

Patients with type 2 diabetes often exhibit a weaker response to incretin hormones, but tirzepatide works by activating both GLP-1 and GIP receptors to counteract this problem.

GLP-1 drug shortages might complicate treatment

Though the results of this study offer hope to patients with multiple health concerns, the availability of GLP-1 class medications like Zepbound is already limited.

Dr. Machineni noted, “Tirzepatide, which is now approved to treat obesity, is effective regardless of how many associated complications a patient might have.”

Dr. Ali shared similar concerns, “The range of patients that stand to benefit from these medications is growing, which unfortunately might exacerbate the ongoing shortage problem we are already witnessing.”

Dr. Jared L. Ross, assistant professor of emergency medicine at the University of Missouri, who did not participate in the study, remarked, “You need to consider that this study's funding comes from Eli Lilly, the manufacturer of tirzepatide.”

“Also, the lead researcher has received significant financial backing from this pharmaceutical company, as reflected in the Open Payments Database under the Sunshine Act,” Ross added. “However, these findings, while expected, still hold value.”

“Most patients struggling with obesity likely have co-occurring health issues, but their awareness of these conditions depends more on their access to primary care services than on their actual health status,” Ross said.

“Tirzepatide, as a dual treatment for both obesity and type 2 diabetes, likely addresses shared mechanisms underlying both metabolic syndromes. As such, it makes sense that the same medication would remain effective in treating patients with both issues. However, one limitation of the study is that the presence of obesity-related conditions was reported by participants themselves.”

— Jared L. Ross, DO, professor of emergency medicine