Characteristics and clinical outcomes in malignant phase hypertension patients using cluster analysis: A report from the West Birmingham Malignant Hypertension Registry

PURPOSE: Malignant hypertension (MHT) is a condition with high morbidity and mortality, necessitating a deeper understanding of its clinical heterogeneity for improved patient management. Aim of our study was to identify/characterize specific phenotypic groups and examine their associations with mortality. METHODS: Data from the West Birmingham MHT Registry were used. We performed two-step cluster analysis to determine distinct groups. Kaplan-Meier curves and Cox proportional hazard models were used to examine the associations of clusters with mortality. RESULTS: 323 patients (mean age 49±13 years; 34 % female) with a median follow-up of 11 (IQR 3-18) years were included. Four clusters were identified; Cluster 1: younger age, intermediate prevalence of cardiovascular risk factors, high prevalence of renal/retinal damage; Cluster 2: older age, female, low prevalence of cardiovascular risk factors, intermediate levels of organ damage; Cluster 3: intermediate age, male, high prevalence of cardiovascular risk factors, high retinal damage; Cluster 4: younger age, male, low prevalence of cardiovascular risk factors, low prevalence of organ damage. In Kaplan Meier curves cluster 4 exhibited the lowest risk, while cluster 3 the highest risk for outcomes (log rank p < 0.001). In Cox regression, all clusters had higher risk of mortality compared to cluster 4; cluster 1 [HR 1.74 (1.07-2.82)], cluster 2 [HR 1.87 (1.20-2.91)], cluster 3 [HR 2.35 (1.54-3.58)]. CONCLUSIONS: Four distinct phenotypic clusters were identified within our registry, having diverse associations with mortality. These clusters offer a framework for more targeted risk stratification and prognostication, with implications for individualized patient care in this high-risk hypertensive population.