The natural history of borderline hypertension in a Chinese population

One hundred and thirty-one borderline hypertensive patients were followed up for 17 years. A cohort of normotensives strictly matched by age, sex, region and occupation served as controls (1:1). It was found that 64.6% of borderline hypertensive patients developed into established hypertensives after 17 years follow-up, 25.5% restored to normotensives and 13.8% remained unchanged. The total mortality rate of borderline hypertensives was higher than that of normotensives (27.9 vs 13.4/1000 person years), and the relative risk of total death in borderline hypertensives was 2.35. The main cause of death was stroke, accounting for 42.5% of the total death rate. The relative risk rates of occurrence and death associated with stroke were 8.3 and 11.6, respectively. It is concluded that the main complication of borderline hypertension was stroke rather than coronary heart disease, which was similar to that of established hypertension in this area. Part of the borderline hypertensives need to be treated to reduce the risk of cardiovascular complications.