People with type 2 diabetes who stop taking weight loss injections may face twice the risk of heart attack, stroke or death compared with those who remain on the medication, according to new research.
A recent study found that people with type 2 diabetes and no established heart disease at the outset fared considerably better in terms of heart health if they continued taking GLP-1 drugs.
Study findings on GLP-1 discontinuation
GLP-1s are already recognised as beneficial for the heart, with studies indicating they can help reduce inflammation and improve blood vessel function. When people shed weight, their blood pressure, inflammation and cholesterol levels tend to improve, which is beneficial for the heart.
For the study, researchers examined electronic medical records from more than 300 diabetes clinics across Italy. The team, which included experts from Italy and Guy's and St Thomas' NHS Foundation Trust in London, identified more than 80,000 people with type 2 diabetes who were taking GLP-1 drugs.
On average, patients who continued treatment took a GLP-1 drug for nearly three years, compared with just over one year for those who discontinued.
Risks and expert commentary
The overall findings suggested that the risk of a non-fatal heart attack, non-fatal stroke or death from any cause was approximately twice as high in people who stopped GLP-1 treatment as in those who carried on. The team noted this is the equivalent of about four strokes or heart attacks per 100 people per year amongst those who stopped, compared with two per 100 amongst those who continued. Amongst those who ceased taking the medication, risks appeared to be greater in individuals who remained obese.
Further findings indicated that discontinuing the drugs may affect the heart regardless of whether people subsequently regained weight or experienced rises in blood sugar and blood pressure.
Writing in the Lancet Regional Health – Europe journal, the research team emphasised that the study was observational, and that those who stopped taking GLP-1 drugs may have already been in poorer health. The reasons behind people stopping were also not considered, but may include side-effects, cost, or illness such as frailty or cancer, they noted.
Dr Sonya Babu-Narayan, clinical director at the British Heart Foundation and consultant cardiologist, said: "These findings suggest that people with type 2 diabetes who stop taking GLP-1 medicines may face a higher risk of future heart attack, stroke or death than those who continue treatment. But there are important caveats to these findings, including that this was an observational study. More research is needed to understand the impact of stopping these medications and on the benefits and risks of being on them long-term. GLP-1 medicines have emerged as important heart medications. For those people who are recommended them by a doctor, it is important they are used in conjunction with heart healthy behaviours. These include eating a varied and balanced diet with plenty of protein and fibre and getting regular physical activity including strength exercises."
Dr Faye Riley, research communications lead at Diabetes UK, said: "We know that GLP-1 medication can help protect against heart attacks and strokes. This study found that people with type 2 diabetes who stopped taking GLP-1s had a higher risk of heart problems compared to those who continued treatment. However, these findings should be interpreted with caution. This was an observational study, so we can't tell whether stopping taking GLP-1s directly raised people's risk of heart attack and stroke, or if those who discontinued treatment were already experiencing health problems. The findings reinforce the importance of supporting people to stay on treatments that work for them. Anyone with type 2 diabetes who is considering stopping treatment should speak to their healthcare team first."
Juliet Bouverie, chief executive of the Stroke Association, noted that both types of diabetes, obesity and high blood pressure heighten the risk of stroke. She went on to say: "Emerging research into GLP-1s is encouraging and adds to growing evidence of their potential benefits beyond blood sugar control and weight management. Whilst further research is needed to understand their role in stroke prevention, these findings highlight the potential for new approaches to reducing stroke risk. At the same time, tackling existing risk factors of stroke – including poor diet, drinking too much alcohol, smoking and not taking regular exercise – remains essential to reduce the growing burden of stroke."
