The Parkinson's Disease Case-Control Study

Inclusion criteria

• For PD patients)
• Men or women aged 50 to 75 years.
• Clinical diagnosis of Parkinson's disease (based on MDS Parkinson's disease diagnostic criteria)
• The patient must have at least two of the following symptoms: static tremor, bradykinesia, stiffness (which must include at least static tremor or bradykinesia); Or have asymmetrical resting tremors or asymmetrical bradykinesia.
• Able to provide informed consent.
• For healthy volunteers)
• Age (±2 years) and sex-matched healthy control individuals for each Parkinson's disease patient.
• Able to provide informed consent.

Exclusion criteria

• For PD patients)
• Atypical or secondary parkinsonism due to medications (e.g., metoclopramide, flunarizine, antipsychotics) or metabolic diseases (e.g., Wilson's disease), encephalitis, or degenerative diseases (e.g., progressive supranuclear palsy).
• The presence of clinically diagnosed dementia as determined by the investigator.
• Previous MRI scans showed clinically significant neurological disorders (as judged by the investigator).
• Serious illness (e.g., heart failure or malignancy).
• Smoking more than 15 cigarettes a day and a history of alcohol or drug addiction
• Inflammatory gastrointestinal diseases.
• Chronic diseases that may affect the gut microorganism (e.g., diabetes, cirrhosis, or cardiovascular disease).
• Blood or autoimmune disease, or use of immunosuppressants in the past 3 months.
• Antibiotics have been used within 3 months prior to sample collection.
• Chronic constipation.
• For healthy volunteers)
• Have a first-degree relative with Parkinson's disease (e.g. biological parent, sibling, or child).
• Current or past clinically significant neurological disorders (as judged by the investigator).
• Previous MRI scans showed clinically significant neurological disorders (as judged by the investigator).
• Use of the following drugs in the 6 months prior to the screening visit: dopamine blockers (antipsychotics), metoclopramide, and riserpine.
• Inflammatory gastrointestinal diseases.
• Smoking more than 15 cigarettes a day and a history of alcohol or drug addiction
• Chronic diseases that may affect the gut microorganism (e.g., diabetes, cirrhosis, or cardiovascular disease).
• Blood or autoimmune disease, or use of immunosuppressants in the past 3 months.
• Antibiotics have been used within 3 months prior to sample collection.
• Chronic constipation.
• Participating in other clinical trials