The incidence of cerebral small vessel disease (CSVD) increases with age, affecting approximately 5% of individuals over 50 years old and nearly all individuals over 90 years old. CSVD is also the most important vascular factor contributing to cognitive decline, with 45% of dementia patients attributed to CSVD. Existing interventions are similar to secondary prevention strategies for cardiovascular and cerebrovascular diseases, and no specific therapies are currently available.

CSVD-related cognitive impairment (CSVDCI) predominantly involves attention, processing speed, and executive functions, with relatively preserved memory function, and may be accompanied by non-cognitive clinical manifestations such as gait disturbances, emotional and behavioral disorders, and bladder dysfunction. Although CSVDCI can be classified under vascular cognitive impairment (VCI), there are certain differences in its clinical manifestations.

In summary, it is necessary to develop more targeted treatments for CSVD. We attempt to establish a "symptom-tongue coating-gut microbiota-imaging" system to provide data support for the subsequent exploration of CSVD treatments based on traditional Chinese medicine (TCM) syndrome differentiation and treatment.

Inclusion Criteria:

1. Age above 50 years (including 50-year-old);
2. MRI confirmed the presence of typical imaging changes of CSVD;
3. Voluntary participation in the study and be willing to sign the Informed Consent Form.

Exclusion Criteria:

1. Patients with acute ischemic stroke or acute intracranial hemorrhage (e.g., epidural hematoma, subdural hematoma, subarachnoid hemorrhage, intracerebral hemorrhage, etc.) or a history of cerebral infarction (non-lacunar) or intracranial hemorrhage within the past 3 months;
2. Significant non-vascular white matter lesions (e.g., multiple sclerosis, adult-onset leukoencephalopathy, metabolic encephalopathy, etc.);
3. Patients with a history of cognitive impairment due to other causes (e.g., normal pressure hydrocephalus, Alzheimer's disease, Parkinson's disease, multiple sclerosis, encephalitis, etc.);
4. Severe hepatic, renal, or cardiac insufficiency (ALT or AST >2 times the upper limit of normal, or serum creatinine >1.5 times the upper limit of normal, or New York Heart Association [NYHA] functional class III or IV);
5. Patients with psychiatric disorders that affect study medication administration and evaluation;
6. Contraindications to MRI examination (e.g., claustrophobia, presence of an implantable pacemaker, etc.);
7. Patients unable to comply with follow-up examinations or other study procedures due to residential location or other reasons;
8. Participation in other clinical trial projects.

The study population mainly consisted of patients from the outpatient and inpatient departments of the Department of Neurology at Dongzhimen Hospital.