Determinants of Malignant Hypertension Onset and Related Target Organ Damages: the HAMA Biobank

Malignant hypertension (MH) is an acute and severe form of hypertension that can lead to rapid target organ damage and potentially be fatal within months if not treated. Despite the severity, MH manifests in various phenotypes, suggesting multiple underlying pathophysiological pathways. The HAMA bank aims to address this by collecting biological samples at two distinct time-points:

For " Pre-existing Patients " in the HAMA cohort: A one-time collection focused on genetic analysis. A full sample (equivalent to sample 1 below) may be collected in option.

For Newly Diagnosed Patients (Incident Patients): Sample 1 "Acute Phase": Collected between Day 0 and Day 7 post-admission to any HAMA recruiting centers. This will be used for initial multi-omics analysis. Sample 2 "Chronic Phase": Collected between the 1st and 6th months during a follow-up visit at the investigating center.

These samples will be cross-referenced with clinical and biological data from the HAMA cohort. The cohort follow-up schedule is: 1, 3, 6, 12 months after MH diagnosis and annually for a total of 5 years.

• biobank (Other): The following samples will be collected : * Serum samples and plasma sample: inclusion visit and follow up visit * Urines samples : inclusion visit and follow up visit * blood DNA: inclusion visit * Blood RNA: inclusion visit and follow up visit

Primary outcomes

• Decipher the mechanisms responsible for the transition from severe to malignant hypertension [At inclusion and 6 month]: Compare the multiomic signature of patients admitted for malignant hypertension, between MHT acute crisis (admission) and resolution (6 month later). Transcriptomic, proteomic and metabolomic evolution between these 2 time points and focus on genetic background in relevant system, like angiogenic, vasoactif system, complement system and inflammasome will be described.

Secondary outcomes

• Understand the determinants of the heterogeneity in target organs damages (TOD) during MHT crisis [At inclusion]: Patient's multiomic signature according to the number of target organ damage presented by the patients, the presence and severity of each TOD (heart, brain, kidney, retina and endothelium) will be compared
• Focus on the role of complement system in MHT crisis [At inclusion and 6 month]: level of circulating complement factors and transcripts between the admission (acute phase of malignant hypertension) and the follow-up consultation will be specificaly compared. Prevalence of pathogenic variant involved in the complement system in the study population will described.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* patients included in the HAMA cohort with the following critera :

  * Malignant hypertension according to the classic definition (Severe hypertension associated with severe hypertensive retinopathy)
  * Severe hypertension associated with acute target organ damage due to high blood pressure

Exclusion Criteria:

* Refusal to participate to the substudy " HAMA bank "
* patient on chronic dialysis

• Romain BOULESTREAU, Principal investigator, University Hospital, Bordeaux