BACKGROUND AND AIMS: Blood pressure (BP) lowering reduces cardiovascular disease (CVD) risk; however, the benefits of treating patients with normal systolic BP but elevated diastolic BP remain uncertain.
METHODS: Data from 51 randomized controlled trials were pooled to compare BP-lowering effects in participants with and without isolated diastolic hypertension (IDH), defined as systolic BP < 130 mmHg and diastolic BP = 80 mmHg. Treatment effects were stratified across baseline diastolic BP categories (range < 60 to =90 mmHg) among individuals with baseline systolic BP < 130 mmHg. Fixed-effect one-stage individual participant data meta-analyses were used, and Cox proportional hazard models, stratified by trial, were applied to analyse the data.
RESULTS: Among 358 325 participants, 15 845 (4.4%) had IDH. At a median follow-up of 4.2 years, a 5 mmHg reduction in systolic BP reduced the risk of major cardiovascular events similarly in individuals with IDH [hazard ratio 0.91; 95% confidence interval (CI) 0.82-1.01] and those without IDH (hazard ratio 0.90; 95% CI 0.89-0.92; P for interaction = 1.00). Analyses by baseline diastolic BP showed no evidence of heterogeneity in treatment effects among individuals with baseline systolic BP < 130 mmHg (P for interaction = .26). Relative treatment effects were not statistically different by CVD history, age, prior medication use, and BP measurement methods.
CONCLUSIONS: The study found no evidence to suggest that pharmacological BP-lowering therapy in individuals with IDH is less or more effective than in those without IDH. Relative risk reductions also did not diminish in those with lower diastolic BP, down to <60 mmHg at baseline. No meaningful differences across various clinical phenotypes were detected.
| Discipline Area | Score |
|---|---|
| Internal Medicine |  |
| Cardiology | |
| Family Medicine (FM)/General Practice (GP) | |
| General Internal Medicine-Primary Care(US) | |
This is an interesting review on this relatively small subset of patients with isolated diastolic hypertension. However, generalizing the results should be done cautiously, especially in patients in whom diastolic hypotension might pose a risk such as those with coronary heart disease. In this regard, about half of patients with IDH had a history of ischemic disease, and therapy-induced diastolic hypotension might risk heart perfusion during diastole. It would be interesting analyzing data in patients under age 40, taking into account the theoretical CV risk of high diastolic blood pressure.
I'd be interested to see whether renal function was stabilised or improved over time. It is a pity the outcomes were limited to cardiovascular effects.
