Blood pressure lowering in isolated diastolic hypertension and cardiovascular risk: an individual patient data meta-analysis.

Summary

Pooling 51 RCTs (n=358,325), this IPD meta-analysis shows that a 5 mmHg reduction in systolic BP reduces major cardiovascular events similarly in isolated diastolic hypertension and non-IDH, with no heterogeneity across diastolic BP levels or key subgroups. Findings support treating IDH with standard BP-lowering strategies.

Key Findings

• Across 358,325 participants (51 RCTs), 5 mmHg systolic BP reduction lowered major cardiovascular events similarly in IDH (HR 0.91; 95% CI 0.82-1.01) and non-IDH (HR 0.90; 95% CI 0.89-0.92).
• No heterogeneity in treatment effect by baseline diastolic BP (P for interaction = 0.26) among those with systolic BP <130 mmHg.
• Relative treatment effects did not differ by prior CVD, age, prior medication use, or BP measurement methods.

Clinical Implications

Clinicians can justify pharmacologic BP lowering in IDH similarly to non-IDH, focusing on overall BP reduction rather than diastolic thresholds, and need not fear harm at lower baseline diastolic pressures.

Limitations

• IDH subgroup represented 4.4% of the pooled population, limiting precision for some estimates
• Trial-level differences and fixed-effect one-stage model assumptions may affect generalizability

Future Directions

Evaluate absolute risk reductions and optimal treatment thresholds in contemporary cohorts; assess patient-centered outcomes and potential J-curve effects in specific populations.