GLP-1 medications used to treat diabetes and obesity were associated with a reduced need for hospital care and sickness absence due to psychiatric reasons, a new study shows. The large register-based study was carried out in collaboration between the University of Eastern Finland, Karolinska Institutet in Stockholm and Griffith University in Australia.
Diabetes and obesity are associated with an increased risk of mental health symptoms, and similarly, individuals with mental disorders have an elevated risk of metabolic diseases such as obesity and diabetes. Researchers have long been interested in the connections between these conditions and in how pharmacological treatments may affect both metabolic and mental health disorders.
The present study included nearly 100,000 participants, over 20,000 of whom had used GLP-1 medications. Participants were followed through Swedish national registers between 2009 and 2022.
The risk of substance use was also reduced
The results showed that the use of GLP-1 medications – particularly semaglutide – was associated with a reduction in sickness absence and hospital care due to psychiatric reasons. During periods of semaglutide use, the reduction was 42% compared with periods when GLP-1 medications were not used. For depression, the risk was 44% lower, and for anxiety disorders, 38% lower.
In addition, semaglutide use was associated with a lower risk of substance use disorders: hospital care and sickness absence related to substance use were 47% lower during periods of semaglutide use compared with periods without GLP-1 medication. The use of GLP-1 receptor agonists was also associated with a reduced risk of suicidal behaviour.
One of the study's authors, Professor Mark Taylor from Griffith University, says such results were to be expected: "An earlier study examining Swedish registers found the use of GLP-1 medications to be associated with a reduced risk of alcohol use disorder. Alcohol-related problems often have downstream effects on mood and anxiety, so we expected the effect to be positive on these as well."
However, the magnitude of the association surprised the researchers:
"Because this is a registry-based study, we cannot determine exactly why or how these medications affect mood symptoms, but the association was quite strong. It is possible that, in addition to factors such as reduced alcohol consumption, weight loss-related improvements in body image, or relief associated with better glycaemic control in diabetes, there may also be direct neurobiological mechanisms involved – for example, through changes in the functioning of the brain's reward system," says Research Director, Docent Markku Lähteenvuo from the University of Eastern Finland.
The study's findings were published in The Lancet Psychiatry, one of the most prestigious journals in the field of psychiatry.
Other recent evidence on the effects of GLP-1 medications on anxiety and depressive disorders has been somewhat inconsistent, but it has been largely based on small studies.