Evaluating Bu Yang Huanwu Decoction For Early Diabetic Vascular Disease

Inclusion Criteria:

1. Aged 18 to 70 years (inclusive), male or female.
2. Diagnosed with diabetes mellitus according to the Chinese Diabetes Society (2024) Guidelines.
3. Glycated hemoglobin (HbA1c) < 12%, with recent fasting blood glucose < 7.0 mmol/L OR postprandial blood glucose < 10.0 mmol/L, and triglycerides < 1.7 mmol/L.

4. Diagnosed with LEAD, meeting the following criteria:

   Rutherford Classification 2, 3, or 4.

   Resting ABI ≤ 0.90, OR for patients with exertional symptoms and resting ABI > 0.90, a post-exercise treadmill test showing an ABI decrease of ≥15%.

   Evidence of lower limb arterial stenosis or occlusion confirmed by duplex ultrasound, CTA, MRA, or DSA.

5. TCM Pattern Diagnosis: Must conform to the TCM syndrome of Qi Deficiency and Blood Stasis, as defined by the study's TCM diagnostic criteria (referencing "Practical Diagnostic Criteria for Blood Stasis Syndrome" and "Integrated Chinese and Western Medicine Peripheral Vascular Disease"):

   Main Symptom: Lower limb weakness, or feeling of heaviness/discomfort after prolonged walking.

   Secondary Symptoms: Shortness of breath/lassitude in speaking; dry mouth with desire to drink; scaly skin.

   Tongue & Pulse: Tongue with teeth marks, pale-purple with petechiae/ecchymosis; thin and choppy pulse.

   (Diagnosis confirmed by meeting 1 main symptom OR 2 secondary symptoms, assessed by a qualified TCM practitioner.)

6. Voluntarily signs the Informed Consent Form (ICF) and is willing and able to comply with all study procedures and visits.

Exclusion Criteria:

1. Known bleeding disorders or history of intracranial hemorrhage.
2. Current use of anticoagulants (e.g., warfarin, dabigatran, factor Xa inhibitors).
3. Presence of active infection.
4. Severe cardiac abnormalities on resting ECG (e.g., heart failure, ventricular tachycardia, ventricular fibrillation, multifocal ventricular contractions, prolonged corrected QT interval).
5. History of acute coronary syndrome ≤ 12 months requiring dual antiplatelet therapy.
6. Chronic liver disease (Child-Turcote-Pugh score ≥5) or chronic kidney disease stages 4-5 (eGFR < 30 mL/min/1.73m²).
7. History of malignancy (except cured basal cell carcinoma).
8. Moderate to severe anemia, polycythemia vera, or any hyperviscosity syndrome.
9. Planned lower limb revascularization or amputation.
10. Concurrent or planned use of medicinal products containing Veratrum species.
11. Pregnant or lactating women, or women of childbearing potential not using highly effective contraception.
12. Known allergy or hypersensitivity to any component of the study medication (Qilong Capsules, aspirin).
13. Patients with psychiatric disorders or judged to be uncooperative.
14. Currently participating in another drug clinical trial or using therapies with similar purported effects.
15. Any other condition deemed by the investigator to make the participant unsuitable for the trial.