TOPLINE:

In a meta-analysis of 51 randomized controlled trials, lowering systolic blood pressure (BP) was linked to similar reductions in the risk for major cardiovascular events in people with and without isolated diastolic hypertension, with benefits consistent across diastolic BP levels, including among those with baseline systolic BP less than 130 mm Hg.

METHODOLOGY:

• Researchers pooled data from 51 randomized clinical trials and conducted an individual participant data meta-analysis to assess whether lowering BP benefited people with isolated diastolic hypertension as much as it did those without isolated diastolic hypertension. Isolated diastolic hypertension was defined as systolic BP < 130 mm Hg and diastolic BP ≥ 80 mm Hg.
• They included 358,325 people, of whom 15,845 (4.4%) had isolated diastolic hypertension. Those with and without isolated diastolic hypertension had mean ages of 60.6 years and 65.2 years, respectively, and 30.0% and 42.1% were women, respectively.
• People had been randomly assigned to receive either BP-lowering medicines or a placebo, usual care, or less intensive treatment.
• Researchers grouped people with systolic BP < 130 mm Hg according to their diastolic pressure levels, ranging from < 60 mm Hg to ≥ 90 mm Hg.
• The primary outcome was the first occurrence of a major cardiovascular event, such as fatal or nonfatal stroke, fatal or nonfatal ischemic heart disease, or heart failure causing death or hospitalization.

TAKEAWAY:

• Over a median follow-up of 4.2 years, 43,506 major cardiovascular events were reported; 1716 occurred in patients with isolated diastolic hypertension.
• A 5-mm Hg drop in systolic BP was linked to similar reductions in the risk for major cardiovascular events in people with and without isolated diastolic hypertension (P for interaction = 1.00). The estimated reduction in risk was about 10% in both groups.
• In people with systolic BP < 130 mm Hg, a 5-mm Hg drop in systolic BP was linked to similar reductions in the risk for major cardiovascular events across all baseline diastolic BP levels, including < 60 mm Hg (P for interaction = .26).
• The risk for major cardiovascular events did not vary by age, prior cardiovascular disease, prior BP medicine use, or BP measurement method and remained unchanged when using an alternative isolated diastolic hypertension definition (systolic BP < 140 mm Hg and diastolic BP ≥ 90 mm Hg).

IN PRACTICE:

“These results suggest the need to reconsider current clinical guidelines, advocating for a more inclusive approach to BP-lowering treatment rather than rigid adherence to the definition of isolated diastolic hypertension based on BP classifications,” the researchers reported.

“[This study] for the first time provides a robust support for initiating or intensifying antihypertensive therapy in patients with isolated diastolic hypertension. However, we should not forget that this support ultimately stems from the lack of statistically significant differences in outcome benefit between patients with systolic-diastolic hypertension and those with [isolated diastolic hypertension]. Randomized trials comparing more vs less tight BP targets are needed in patients with isolated diastolic hypertension to conclusively prove the benefits of treatment on outcomes,” experts wrote in an accompanying editorial.

SOURCE:

The study was led by Zeinab Bidel, University of Oxford, Oxford, England. It was published online on December 12, 2025, in the European Heart Journal.

LIMITATIONS:

The study had limited statistical power to test differences in certain subgroups of isolated diastolic hypertension. Data on treatment-related adverse events were not available. Not all eligible trials were included, which may have limited completeness.

DISCLOSURES:

The study was funded by grants from the British Heart Foundation. One author reported receiving honoraria from several sources including Medscape Medical News, WebMD, and Medscape UK and from other organizations including the funding agency. Several authors reported receiving research support, honoraria, fees from and having other financial ties with multiple organizations including the UK Research and Innovation Medical Research Council, the National Institute for Health and Care Research, and various pharmaceutical and healthcare companies. 

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.