Explainer · Brain & Mental Health
Semaglutide use tied to 21% fewer psychiatric hospital stays in people with bipolar disorder
Bipolar disorder often comes with diabetes and weight gain. Swedish records comparing the same people on and off GLP-1 drugs found fewer hospital admissions while they took semaglutide, but not other drugs in the class.
- An observational study of 14,694 people in Sweden with bipolar disorder who took diabetes medicines, 2009 to 2024.
- Each person was compared with themselves, in periods on and off GLP-1 drugs.
- Semaglutide periods went with 21% fewer psychiatric hospital admissions and 17% fewer bipolar relapses.
- Liraglutide and dulaglutide showed no such link, suggesting this is not a class-wide effect.
- Changing circumstances could still explain some of it, and a randomized trial is needed.
Bipolar disorder and type 2 diabetes often go together. Some mood medicines also cause weight gain. So many people with bipolar disorder end up on diabetes drugs, including the GLP-1 drugs now widely used for weight loss. What those drugs do to mood has been an open question.
A study in Acta Psychiatrica Scandinavica used Swedish national records for 14,694 people with bipolar disorder who took diabetes medicines. Periods on semaglutide went with about a fifth fewer psychiatric hospital stays, while two older drugs in the class showed no such link.
What bipolar disorder involves
MedlinePlus explains that along with mood swings, bipolar disorder causes changes in behavior, energy levels, and activity levels. In bipolar I, the highs can be severe enough that people need hospital care. Bipolar II involves low moods and milder highs.
Treatment has changed little in years. As the authors write, diabetes, obesity and bipolar disorder often co-occur and may have shared pathophysiology, and they set out to test whether GLP-1 drugs, used for diabetes and obesity, affect the course of the illness.
How the Swedish bipolar study worked
The researchers used national records. They covered everyone in Sweden with bipolar disorder who used any diabetes medicine from 2009 to 2024. Of 14,694 people, 5,200 used a GLP-1 drug at some point.
Each person was compared with themselves, in periods on and off the drugs. The authors say this design was used for all comparisons to reduce confounding, meaning to remove differences between people. The main outcome was a psychiatric hospital stay for any reason. The team also looked at bipolar relapses and sick leave.
What happened to hospital admissions
Semaglutide stood out. Periods on it went with 21% fewer psychiatric hospital stays, compared with periods off GLP-1 drugs in that same individual. Admissions for a bipolar relapse were 17% lower.
The other GLP-1 drugs did not show the same pattern. Liraglutide and dulaglutide did not go with fewer hospital stays. The authors take this as a sign that the link is not shared by the whole drug class. Sick leave for psychiatric reasons did not differ across the diabetes medicines studied.
Why a semaglutide signal matters in bipolar disorder
People with bipolar disorder die earlier than average, mostly from heart and metabolic disease. So drugs that treat diabetes and weight matter in their own right. A drug that also steadied mood would be doubly useful.
Only semaglutide showed a link, and it is the newest and strongest of the three. The authors say the semaglutide result should be further tested in a randomized controlled trial. Until then, no one should treat it as a mood medicine.
What a register study of GLP-1 drugs cannot prove
Comparing people with themselves removes fixed differences but not changing ones. Someone who starts semaglutide may also see doctors more, lose weight, sleep better or take other drugs differently. Any of those could affect mood.
The study covered only people already on diabetes drugs. It says nothing about semaglutide in people with bipolar disorder who do not have diabetes or obesity. A hospital stay is also a blunt measure of how people feel day to day.
What this changes for people with bipolar disorder
For people with bipolar disorder who also have diabetes or obesity, this is reassuring. A drug they may be offered did not go with worse mental health outcomes, and may go with better ones.
It is not a reason to seek semaglutide for mood, and psychiatric medicines should never be changed without advice. Choices about diabetes and weight treatment are best made with both a psychiatrist and the doctor who manages diabetes.
People also ask
What did the study find?
Semaglutide was associated with a 21% lower risk of psychiatric hospitalization (adjusted hazard ratio 0.79, 95% CI 0.69 to 0.91) and a 17% lower risk of relapse of bipolar disorder (0.83, 0.69 to 0.99) compared with periods of GLP-1 non-use in the same individuals. Liraglutide and dulaglutide were not associated with lower hospitalization risk, and sick leave did not differ.
What is a within-individual design?
Each person serves as their own comparison, with periods on a drug compared against periods off it. That removes stable differences between people, such as genetics or illness severity, though not changes over time.
Why study GLP-1 drugs in bipolar disorder?
Diabetes, obesity and bipolar disorder often occur together and may share biology. Some psychiatric medicines also cause weight gain, which GLP-1 drugs can help manage.
Why might only semaglutide show a benefit?
The study did not test reasons. Semaglutide may reach the brain more effectively or act more strongly than older GLP-1 drugs, but that is speculation until tested.
Should people with bipolar disorder take semaglutide for their mood?
No. It is not approved or tested as a bipolar treatment, and this study included only people who were already prescribed diabetes medicines. The authors call for a randomized trial.
What should someone with bipolar disorder and diabetes do?
Discuss diabetes and weight options with both a psychiatrist and a diabetes specialist, and never change psychiatric medicines without advice. This is general information rather than medical advice.