Summary
A large Swedish registry study suggests that GLP-1 receptor agonists — notably semaglutide (marketed as Ozempic and Wegovy) and liraglutide — are associated with a lower risk of worsening anxiety and depression among people treated with diabetes medications. The analysis also found fewer psychiatric hospitalizations and less psychiatric sick leave during periods when patients were using these drugs. Authors and outside clinicians stress that the study is observational and that randomized trials are required before GLP-1s can be recommended as primary psychiatric treatments.
Study design
Investigators used national electronic health registers to follow 95,490 people in Sweden who had diagnoses of depression, anxiety, or both and who were prescribed diabetes medications between 2009 and 2022. They used a within-individual design in which each person served as their own control, comparing outcomes during periods on GLP-1 receptor agonists with periods off them. This design reduces confounding by stable personal factors (for example, sex or baseline health). Average follow-up was 5.2 years, and about 23.5% of participants used a GLP-1 drug during the study period.
Outcomes
The primary composite outcome defined worsening mental illness as any of: psychiatric hospitalization, extended sick leave for psychiatric reasons, hospitalization for self-harm, or suicide. Secondary outcomes included worsening of depression or anxiety separately, new or worsening substance use disorders, and self-harm events. The researchers also compared GLP-1s with other second-line diabetes drugs (for example, SGLT2 inhibitors like empagliflozin/Farxiga and DPP-4 inhibitors like sitagliptin/Januvia) to assess whether observed effects might be independent of glucose control.
Key findings
– Semaglutide use was associated with a 42% lower risk of the composite measure of worsening mental illness compared with the same individuals’ periods off GLP-1 treatment.
– Liraglutide use was linked to an 18% reduced risk; exenatide and dulaglutide showed no significant associations.
– Semaglutide was associated with lower risks of worsening depression, anxiety, and substance use disorders, while liraglutide’s effect was mainly on depression.
– As a class, GLP-1 receptor agonists were associated with a reduced risk of self-harm.
– Direct comparisons with other second-line antidiabetic medications showed semaglutide’s favorable mental health associations persisted, suggesting benefits beyond glycemic control. The reductions translated into fewer psychiatric hospitalizations and less psychiatric sick leave.
Analyses and robustness
Models adjusted for time-varying factors such as treatment order and concurrent medications. Sensitivity analyses addressed potential biases (medication sequence effects, carryover between periods) and remained consistent when excluding early days after starting or stopping drugs and when focusing on use after official approval dates.
Possible mechanisms
Hypothesized mechanisms include central nervous system effects: some GLP-1 agents cross the blood–brain barrier and interact with brain circuits involved in reward and mood, may modulate dopamine signaling (which can affect impulsivity and cravings), and have anti-inflammatory properties that could reduce neuroinflammation linked to mood disorders.
Caveats and implications
This is observational evidence and cannot prove causation. Clinicians caution against using GLP-1 receptor agonists as primary treatments for depression or anxiety until randomized controlled trials confirm efficacy, dosing, and safety for psychiatric indications. Nonetheless, the findings highlight a potential dual benefit for patients with overlapping metabolic and psychiatric conditions and support further research at the intersection of psychiatry, addiction medicine, and metabolic health.
