Use of Glucagon-Like Peptide-1 Receptor Agonists and Risk of Parkinson's Disease: Scandinavian Cohort Study.

PubMed17 Apr 2026·Diabetes, obesity & metabolism● 7/10i

Use of Glucagon-Like Peptide-1 Receptor Agonists and Risk of Parkinson's Disease: Scandinavian Cohort Study.

Engström A, Svanström H, Hviid A, Eliasson B, Gudbjörnsdottir S et al.

GLP-1 receptor agonists reduced Parkinson's disease risk by 19% versus sulfonylureas in adults with type 2 diabetes, with incidence rates of 5.2 versus 8.0 per 10,000 person-years. Scandinavian cohort study of 347,026 new users across three countries, with liraglutide accounting for 73% of GLP-1 exposure followed by semaglutide at 13%. This provides the first large-scale evidence for neuroprotective effects beyond weight loss and glycemic control in the GLP-1 class. The observational design cannot establish causation, requiring validation in randomized trials.

Strategic signal

This neuroprotective signal creates a differentiation opportunity for Novo Nordisk and Eli Lilly in neurology markets where Parkinson's treatments are limited to symptomatic management. Regulatory agencies may request dedicated neurological safety monitoring in ongoing cardiovascular outcomes trials, potentially adding development costs but enabling neuroprotection claims if confirmed. The finding positions GLP-1s for potential label expansions into neurodegenerative diseases, opening a $7 billion Parkinson's market dominated by generic dopamine therapies.

GLP-1Brain/NeuroType 2 diabetesNovo Nordisk Eli Lilly

Original Abstract

AIMS: To investigate the association between use of GLP-1 receptor agonists and incident Parkinson's disease. MATERIAL AND METHODS: Cohort study using data from nationwide registers in Denmark, Norway and Sweden and an active-comparator, new-user design. We included 158 961 new users of GLP-1 receptor agonists and 188 065 new users of sulfonylureas, aged 45 years or older. Liraglutide accounted for 72.9% of GLP-1 receptor agonist follow-up time, followed by semaglutide (13.4%), exenatide (7.3%), dulaglutide (5.1%) and lixisenatide (1.3%). The primary outcome was incident Parkinson's disease, defined as a first-ever diagnosis of Parkinson's disease (ICD-10 G20) or Parkinson's disease dementia (ICD-10 F02.3) in national patient registers. Cox regression with propensity score weighting was used to estimate hazard ratios (HRs) and control for confounding. RESULTS: Mean age was 65 years and 43% were female. Incidence rates for Parkinson's disease were 5.2 and 8.0 per 10 000 person-years among GLP-1 receptor agonist and sulfonylurea users, respectively (adjusted HR 0.81 [95% CI 0.68-0.96]). Results were consistent in a 2-year lag-time analysis (HR 0.84 [95% CI 0.70-1.02]) after excluding or censoring users of DPP-4 inhibitors at cohort entry or during follow-up (HR 0.74 [95% CI 0.60-0.93]) and in subgroup analyses by sex and age. CONCLUSION: In this large observational cohort study, use of GLP-1 receptor agonists compared with sulfonylureas was associated with a lower risk of incident Parkinson's disease. These findings support a potential neuroprotective role of GLP-1 receptor agonists, though replication in additional studies is needed.

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