Based on clinical manifestations, laboratory data and intestinal microflora detection, the cognitive function characteristics of patients with systemic lupus erythematosus and cerebrovascular disease and its relationship with intestinal microflora were analyzed to explore the possible pathogenesis of lupus cerebrovascular disease.

This study was a retrospective and prospective cohort study. They were divided into three groups, namely SLE group, SLE cerebrovascular disease group and healthy control group. Each group included 60 patients [Anticipated].

1. Retrospective study: The SLE patients admitted to Nanfang Hospital from 2018 to 2022 were retrieved. The patients enrolled from September 2018 to September 2021 applied for exemption from informed consent, and the patients enrolled from September 2021 to September 2022 voluntarily signed informed consent. Patients were selected according to inclusion and exclusion criteria, and clinical and laboratory data of all subjects were recorded.
2. Prospective study: Obtain the consent of the subjects, sign the informed consent, and record the clinical and laboratory examination data of all the subjects.

(1) Cognitive function assessment; (2) Fresh stool and serum were collected, and 16s rRNA technology was used for intestinal flora detection, and QIIME2 platform was used for flora analysis; Serum inflammatory factors were detected and metabolomic analysis was performed.

The clinical data of all enrolled patients were statistically analyzed.

Inclusion Criteria:

Retrospective study

• Patients enrolled from September 2018 to September 2021 applied for exemption from informed consent, and patients enrolled from September 2021 to September 2022 signed informed consent voluntarily.
• Male or female patients aged 14-55 years;
• Patients diagnosed with systemic lupus erythematosus are classified according to the European League against Rheumatism (EULAR)/American College of Rheumatology (ACR) joint classification criteria for SLE in 2019.
• Cranial imaging examination was performed, and the results of cranial imaging examination were consistent with cerebrovascular disease changes.

Prospective Research:

SLE group:

• The researcher signed the informed consent voluntarily;
• Male or female patients aged 14-55 years;
• Patients diagnosed with systemic lupus erythematosus are classified according to the European League against Rheumatism (EULAR)/American College of Rheumatology (ACR) joint classification criteria for SLE in 2019.
• Patients who need to undergo head imaging examination according to the judgment of treating doctors, and the results of head imaging examination are not consistent with changes in cerebrovascular disease.
• No antibiotics have been taken in the past 2 weeks; SLE cerebrovascular disease group
• The researcher signed the informed consent voluntarily;
• Male or female patients aged 14-55 years
• Patients diagnosed with systemic lupus erythematosus are classified according to the European League against Rheumatism (EULAR)/American College of Rheumatology (ACR) joint classification criteria for SLE in 2019.
• no antibiotics have been taken in the past 2 weeks;

Healthy control group:

• Male or female patient volunteers aged 14-55 from the Health Examination Center of Nanfang Hospital,
• Voluntary signing of informed consent;
• No systemic disease;
• According to the judgment of the researchers, healthy volunteers matching SLE group in age, gender and education level were selected as the control group;

Exclusion Criteria:

• Patients with other autoimmune diseases;
• Brain imaging suggested central nervous system infection, space occupation and other manifestations.
• Patients with malignant tumors and active tuberculosis;
• Pregnancy, lactation or intended pregnancy, women of childbearing age do not use effective contraceptive measures (IUD, oral contraceptives and obstruction measures);
• History of cerebrovascular disease not associated with SLE as determined by the investigator
• The researcher judged that it is not suitable to participate in this researcher.

Diagnostic criteria: Patients diagnosed with systemic lupus erythematosus are classified as SLE by the European League against Rheumatism (EULAR)/American College of Rheumatology (ACR) 2019.

Brain imaging cerebrovascular changes were defined as: great vascular lesions including cerebral infarction, cerebral hemorrhage, venous sinus thrombosis; Microvascular lesions include leukodystrophy, cerebral atrophy, perivascular space enlargement, lacunar infarction, cerebral microhemorrhage focus, and recent subcortical infarction.