The goal of this clinical trial is to conduct a dietary intervention targeting HIV-specific gut microbiota alterations for primary ASCVD prevention and evaluate its effectiveness in preventing borderline ASCVD risk among HIV-infected patients. The main questions it aims to answer are:

• Explore the pivotal role of the gut-heart axis in the causal relationship between HIV infection and atherosclerotic cardiovascular disease.
• Develop a targeted dietary intervention focusing on gut microbiota to prevent the borderline risk of atherosclerotic cardiovascular disease in HIV-infected patients.
• Evaluate the effectiveness of the gut microbiota-targeted dietary intervention in reducing atherosclerotic cardiovascular disease risk among HIV-infected patients, altering gut microbiota composition, improving risk factors of atherosclerotic cardiovascular disease, and alleviating prodromal symptoms associated with atherosclerotic cardiovascular disease.

Participants in the intervention group will receive the gut microbiota-targeted dietary intervention thrice weekly for 3 months, accompanied by bi-weekly health education videos for the same duration. Meanwhile, the control group will continue routine follow-up and health education practices. The intervention will span three months, followed by a three-month follow-up period. Data collection will occur at baseline, 3 months, and 6 months.

Methods and data:

1. Mendelian randomization A two-step, two-sample mendelian randomization will be employed to investigate the potential mediating roles of gut microbiota in the causal relationship between HIV and atherosclerotic cardiovascular disease. Utilizing GWAS summary statistics from the Medical Research Council Integrative Epidemiology Unit OpenGWAS data and the MiBioGen study, we will conduct univariable mendelian randomization. The first step involves examining the causal pathway of HIV infection on gut microbiota (the coefficient=α), followed by elucidating the influence of gut microbiota on the development of atherosclerotic cardiovascular disease (the coefficient=β). The multiplication of these estimates (α*β) will delineate the mediation effects attributed to gut microbiota. Identification of specific gut microbiota exhibiting substantial mediation effects will guide the selection of our targeted intervention.
2. Systematic review To establish an empirical research foundation, a systematic review will synthesize evidence concerning the correlation between dietary patterns and gut microbiota, as well as the relationship between microbiota and atherosclerotic cardiovascular disease among people living with HIV. A thorough systematic search across database including PubMed/MEDLINE, MEDLINE (Ovid), Embase (Ovid), CINAHL (EBSCO), Web of Science, and China National Knowledge Infrastructure (CNKI). Articles meeting predefined inclusion and exclusion criteria will undergo rigorous extraction and summarization processes.
3. Intervention design and expert evaluation The intervention protocol will be formulated, drawing from the gut microbiota identified demonstrating significant mediation effects in the causal association between HIV infection and atherosclerotic cardiovascular disease, along with insights gleaned from the systematic review. Subsequently, multidisciplinary experts will be invited to evaluate the drafted protocol using the FAME (Feasibility, Appropriateness, Meaningfulness and Effectiveness) scale developed by the Joanna Briggs Institute.
4. Pragmatic randomized controlled trial We utilize a pragmatic randomized controlled trial design to evaluate the effectiveness of dietary intervention in real-world conditions, without strict control, thereby enhancing the generalizability and clinical applicability of our study findings. Participants at Shenzhen Third People's Hospital, exhibiting HIV with a borderline risk of atherosclerotic cardiovascular disease (5% to <7.5%) determined by the pooled cohort equation, will be enrolled. Upon providing informed consent, participants will undergo dynamic randomization into intervention and control groups, aiming for a 1:1 ratio while preserving maximum unpredictability. The intervention group will receive the gut microbiota-targeted dietary intervention thrice weekly for 3 months, accompanied by bi-weekly health education videos for the same duration. Meanwhile, the control group will continue routine follow-up and health education practices. The intervention will span three months, followed by a three-month follow-up period. Data collection will occur at baseline, 3 months, and 6 months. Primary outcomes will assess atherosclerotic cardiovascular disease risk via the pooled cohort equation and evaluate gut microbiota diversity and composition. Secondary outcomes will encompass biomarkers and predictors associated with atherosclerotic cardiovascular disease, as well as symptoms related to the condition.

Inclusion Criteria:

1. HIV-infected patients diagnosed according to the diagnostic criteria of China AIDS diagnosis and treatment guidelines (2021 edition);
2. Aged 18 years and above;
3. PCE predicted ASCVD risk of 5% - <7.5%;
4. Those with a predicted survival time of >1 year;
5. No plans to leave the depth in the next 3 months;
6. Voluntary participation in this study and signing the informed consent.

Exclusion Criteria:

1. Those with a past history of CVD;
2. Those with HIV-related neurocognitive disorders and various serious opportunistic infections;
3. Those with diabetes mellitus;
4. Known nut allergy;
5. Planning to become pregnant within 6 months;
6. Are on lipid-lowering therapy or using any interfering medications or diets;
7. Are participating in other HIV-related or dietary intervention-related scientific research programs.