Yet another positive side effect of blockbuster diabetes and weight-loss drugs has come to light, after recent studies suggested that people with type 2 diabetes on GLP-1 receptor agonists were less likely to develop TB or land up in hospital or die from infections, reports MedPage Today.
In an international study of more than 7m people, type 2 diabetics taking a GLP-1 drug were less likely to develop TB than those on other anti-diabetic medications, including DPP-4 inhibitors (HR 0.49, 95% CI 0.43-0.56), sulfonylureas (HR 0.53, 95% CI 0.47-0.59), metformin (HR 0.60, 95% CI 0.51-0.70), and SGLT2 inhibitors (HR 0.82, 95% CI 0.72-0.92).
“These findings suggest that beyond their established metabolic benefits, GLP-1 receptor agonists may confer additional advantages in lowering infection risk,” wrote Chih-Cheng Lai, MD, of Chi Mei Medical Centre in Taiwan, and colleagues in Nature Communications.
And in a real-world study that backed the major adverse cardiovascular events (MACE) benefit for tirzepatide (Mounjaro, Zepbound), the GLP-1 drug was also linked to protection against serious infections.
Published in The BMJ, the cohort study of more than 50 000 US adults with type 2 diabetes and atherosclerotic cardiovascular disease found that tirzepatide was associated with substantially lower one-year risks for various infection outcomes than sitagliptin (Janumet), a DPP-4 inhibitor:
• Infection-related mortality: HR 0.40 (95% CI 0.26-0.61)
• Infection-related hospitalisation: HR 0.64 (95% CI 0.55-0.75)
• Urinary tract infections: HR 0.83 (95% CI 0.76-0.91)
• Infections in any care setting: HR 0.83 (95% CI 0.78-0.87)
A reduction in all-cause mortality among the tirzepatide users was also observed in the study from researchers led by Nils Krüger, MD, of Harvard Medical School in Boston.
“One plausible explanation that our study supports is the substantial reduction in serious bacterial infections among individuals who initiated tirzepatide, suggesting that part of the survival benefit may reflect effects beyond atherosclerotic mechanisms,” wrote Krüger and colleagues.
Together, the two studies lend support to a recent umbrella review with convincing evidence that GLP-1 medications had protective associations against infection-related outcomes, especially for serious infections.
People with diabetes have an increased risk for active TB and worse subsequent outcomes, according to the CDC. And past research has suggested that obesity may be responsible for one in 10 infection-related deaths in adults. Obesity’s ties to increased systemic inflammation, immune system dysfunction, and metabolic disturbances are likely to help drive that association.
Based on preclinical and translational data, Lai and co-authors suggested that GLP-1 drugs could influence people’s susceptibility to infections and outperform other classes of antidiabetics at lower infection risk.
“In obese, high-fat diet-induced diabetic mice, GLP-1RA [receptor agonists] outperformed insulin in restoring host defence against infection by enhancing neutrophil phagocytosis, migration, and bacterial clearance,” they wrote.
“Prolonged GLP-1RA treatment further improved infection resistance by correcting hyperglycaemia, increasing neutrophil counts, and restoring innate immune competence,” they added.
“These improvements indicate that GLP-1RA may provide a superior anti-infective effect compared with conventional therapy, not only through glycaemic control but also by directly enhancing immune cell function.”
Beyond their long-proven benefits for type 2 diabetes or/and obesity, GLP-1 drugs such as tirzepatide and semaglutide (Ozempic, Wegovy) have garnered a growing number of FDA-approved indications for conditions including chronic kidney disease, sleep apnoea, and metabolic-dysfunction associated steatohepatitis, and to reduce the risk for MACE.
And observational and small randomised studies have suggested other potential benefits as well, including cancer risk or recurrence reduction and for people with addictions to alcohol or opioids.
The research
For the TB study, the investigators drew on 2017 to 2025 data from the TriNetX international health research network. After adjustment, baseline characteristics – such as age, sex, race, HbA1c, body mass index, and comorbidities – were well balanced within each cohort, which were divided up by antidiabetic medication class.
Limitations included a lack of data on key clinically relevant TB variables, limiting analysis of GLP-1 receptor agonists effects across TB exposure patterns and disease phenotypes. In addition, substantial variation in TB epidemiology across countries could have introduced geographical confounding.
In the MACE study, the researchers analysed data from two US administrative claims databases from 2022 to 2025 on adults 40 and over with type 2 diabetes and atherosclerotic cardiovascular disease. Median patient age was 70, 51% were women, and 85% took statins.
Limitations included the relatively short follow-up period, which could underestimate long-term cardiovascular and safety effects.
Study details
Glucagon-like peptide-1 receptor agonists and risk of TB in type 2 diabetes
Kuang-Ming Liao, Jheng-Yan Wu & Chih-Cheng Lai.
Published in Nature Communications on 22 August 2026
Abstract
Tuberculosis remains a leading cause of illness and death worldwide, and individuals with type 2 diabetes have an increased risk of developing this infection. However, whether different glucose-lowering medications influence this risk is unclear. Here we show that use of glucagon-like peptide-1 receptor agonists is associated with a lower risk of tuberculosis compared with several commonly prescribed alternatives. We conducted a multicentre cohort study using TriNetX electronic health records from 143 healthcare organizations across multiple countries between 2017–2025. Patients receiving glucagon-like peptide-1 receptor agonists were compared with those receiving sulfonylureas, metformin, dipeptidyl peptidase-4 inhibitors, or sodium-glucose cotransporter-2 inhibitors. Propensity score matching and time-to-event analyses were applied over up to 5 years of follow-up. Use of glucagon-like peptide-1 receptor agonists is consistently associated with reduced tuberculosis risk compared with other agents. Incidence rates per 1,000 person-years ae lower than with sulfonylureas (0.68 vs 1.67; hazard ratio 0.53, 95% confidence interval 0.47–0.59), metformin (0.65 vs 1.31; 0.60, 0.51–0.70), dipeptidyl peptidase-4 inhibitors (0.73 vs 1.71; 0.49, 0.43–0.56) and sodium-glucose cotransporter-2 inhibitors (0.89 vs 1.02; 0.82, 0.72–0.92). These findings suggest that this class of medications may provide additional protection against tuberculosis in patients with type 2 diabetes.
MedPage Today article – GLP-1 Studies Suggest Benefits Extend to Infectious Diseases (Open access)
See more from MedicalBrief archives:
Major US review maps effectiveness of GLP-1 drugs
Boundless benefits of weight-loss drugs under scrutiny
Tirzepatide effective for obstructive sleep apnoea – US study