THE ARISING · Longevity & Healthspan
Sustained GLP-1 Use Linked to Lower Diabetes Incidence in Over-65s
Older adults with obesity who kept filling prescriptions for a GLP-1 drug were less likely to be diagnosed with diabetes than those who filled only one or two, according to a large study of health records from Israel.
The work was published in Diabetes, Obesity and Metabolism. It is a retrospective cohort study, which means the researchers looked back at existing records in people. It is observational. It did not assign anyone to a treatment, so it cannot show that the drugs caused the differences. The authors say this themselves: the findings describe observed changes after treatment initiation, not a proven causal treatment effect.
The data came from Clalit Health Services in Israel. The study included 13,387 adults aged 65 or older. All had obesity, defined as a body mass index (BMI) of 30 or higher, and none had diabetes at the start. Each had at least two BMI measurements. Sixtynine percent were women.
The researchers sorted people by how many times they collected a GLP-1 receptor agonist prescription. Those with one or two dispensations were classed as minimal exposure. Those with three or more were classed as sustained exposure. By this definition, 11,121 people (83%) were in the sustained group and 2,266 (17%) were in the minimal group.
The main outcome was whether a person moved to a lower BMI category, such as from one obesity band to a lighter one. This happened in 55% of the sustained group and 30% of the minimal group. The researchers adjusted their analysis for age, sex, socioeconomic status and other medical conditions.
They also looked at HbA1c, a blood test that reflects average blood sugar over recent months. In the subset of people with two HbA1c readings, the sustained group showed greater improvement in HbA1c category. The sustained group was also diagnosed with diabetes less often.
The main caution is that people who keep taking a drug may differ from those who stop. They may tolerate it better, have different health habits or have different access to care. Adjusting for some factors cannot remove every such difference. Having three prescriptions filled also does not say how long someone took the drug or at what dose. This is where the finding is weakest.
The results address a different question from a piece The Arising ran on October 21, which reported on GLP-1 drugs plus metformin and dementia in people who already had type 2 diabetes. This study looks at older adults without diabetes and at weight and blood sugar measures, so it adds to the broader picture without testing the same thing.
For now, the finding is a signal that deserves testing, not a reason to change treatment. Trials that randomly assign older adults to a GLP-1 drug or not, and follow them for diabetes, would show whether the link holds.