Introduction: The widespread use of antihypertensive medication and the increasing frequency of diagnosis of mild-to-moderate hypertension should mean that malignant-phase hypertension should be becoming less common, and this trend has been reported elsewhere. No decline in the incidence of malignant hypertension has been apparent in our practice in a district general hospital in a city centre.
Objective and methods: To investigate the incidence and mode of clinical presentation of patients presenting with malignant hypertension, we performed a retrospective survey of the number of patients presenting with malignant hypertension to our hospital, over the 24-year period from 1970 to 1993. We identified a total of 242 patients (155 male, 87 female; mean +/- SD age 50.1 +/- 13.3 years) with malignant hypertension.
Results: There were no significant differences in the number of patients presenting each year, the mean age or the presenting systolic and diastolic blood pressures over the period surveyed. At presentation, 131 patients (54.1%) had no previous history of hypertension; 161 (66.5%) were receiving no antihypertensive therapy and only 70 (28.9%) were receiving antihypertensive treatment (with no record of therapy in 11 patients). The most common presenting symptoms included visual disturbance in 62 (25.6%), headaches in 29 (12.0%), headaches and visual disturbance in 24 (9.9%), heart failure in 19 (7.9%), stroke or transient ischaemic attack in 17 (7.0%) and dyspnoea in 13 (5.4%), although 23 patients (9.5%) were asymptomatic. The most common presenting complications were heart failure [27 patients (11.1%)], stroke [23 patients (9.5%)], angina [10 patients (4.1%)], myocardial infarction [nine patients (3.7%)] and chronic renal failure [77 patients (31.7%)]. In the whole group the majority (147 patients, 60.5%) had no complicating clinical features. Primary or essential hypertension was the most common underlying cause in 137 patients (56.4%). Secondary causes of hypertension (mainly renal disease) were identified in 97 patients (39.9%).
Conclusion: Our experience suggests that malignant hypertension is still common, with a small proportion of hypertensives presenting each year. In particular, the incidence has failed to decline in Birmingham. The incidence rate in the population served by our hospital is approximately 1-2 cases per 100,000 per year. An awareness of the different presenting clinical features is required to allow better recognition and management of this life-threatening condition.