Predictors of 5-year outcomes in malignant phase hypertension: the West Birmingham Malignant Hypertension Registry

Objective: Malignant hypertension represents a high-risk condition and there are scarce data on current clinical patterns of this condition. The aim of the study is to identify the clinical and demographic factors associated with poor outcome. Methods: The data collected from 1958 to May 2016 included a total of 351 patients whose 5-year survival status was known: 221 white Caucasians (63%, age 51 +/- 13 years, 64% male), 83 African-Caribbeans (24%, 45 +/- 11 years, 61% male), and 47 South Asians (13%, 42 +/- 11 years, 74% male). Results: During the 5-year follow-up 119 (34%) patients suffered a primary outcome, defined as the composite endpoint of death or dialysis. The 5-year mortality ranged from 76% in patients diagnosed before 1967 to 7% in patients diagnosed between 1997 and 2006. The independent predictors of outcome were advanced age (vs. a reference group of < 40-year-old; P = 0.01 for age at presentation 51-60 years, P<0.001 for age > 60 years), prior use of antihypertensive medications (P = 0.002), higher serum creatinine (P = 0.006), and proteinuria (P<0.01). Also, white Caucasian (odds ratio12.02, 95% confidence interval 1.64-88.15, P = 0.01) and African-Caribbean (odds ratio 15.55, 95% confidence interval 2.06-117.29, P = 0.008) origins were associated with higher mortality vs. South Asians. The years of the diagnosis after 1977 were significantly associated with lower composite endpoint of death or dialysis, all P<0.01. Conclusion: There has been a major improvement in 5-year survival in patients with malignant hypertension over recent decades. Abnormal renal function at presentation still predicts worse outcome. South Asian ethnicity is also associated with better outcome, although mechanisms involved are yet to be established.