Isolated Diastolic Hypertension Research Findings

Isolated diastolic hypertension not associated with increased cardiovascular (CV) risk in later life is a new research finding.

In the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) guideline, the definition of hypertension was lowered from a blood pressure (BP) of greater than or equal to 140/90 to greater than or equal to 130/80 mm Hg. The new diastolic BP threshold of 80 mm Hg was recommended based on expert opinion and changes the definition of isolated diastolic hypertension.

This showed that the prevalence was estimated at 6.5% in National Health and Nutrition Examination Survey (NHANES) data under the 2017 American College of Cardiology/American Heart Association definition of hypertension as 130/80 mm Hg or greater compared with just 1.3% under the prior 140/90 mm Hg threshold.

Researchers conducted a nationally representative US cross-sectional study to compare the prevalence of IDH in the United States, by 2017 ACC/AHA and 2003 Joint National Committee (JNC7) definitions, and to characterize cross-sectional and longitudinal associations of IDH with outcomes.

The researchers found that diastolic hypertension using the stricter hypertension definition imposed by the American College of Cardiology/American Heart Association (ACC/AHA) in 2017 is not associated with adverse cardiovascular outcomes, according to a JAMA report. In other words, isolated diastolic hypertension (IDH) as defined by the 2017 ACC/AHA blood pressure guideline may not be associated with increased risk for cardiovascular outcomes.

The ACC/AHA 2017 hypertension cutoff for diastolic blood pressure is 80 mm Hg, while the older Joint National Committee 7 (JNC7) cutoff was more lenient at 90 mm Hg.

• First, researchers studied roughly 9600 adults who participated in the National Health and Nutrition Examination Survey (NHANES) during 2013–2016. The prevalence of isolated diastolic hypertension was estimated at 6.5% using the ACC/AHA 2017 cutoff and 1.3% using the JNC7 cutoff.
• Next, the researchers examined long-term outcomes according to isolated diastolic hypertension in another large U.S. cohort. During a median follow-up of 25 years, isolated diastolic hypertension using either the ACC/AHA 2017 or JNC7 cutoff was not significantly associated with increased risks for incident atherosclerotic cardiovascular events, heart failure, or chronic kidney disease, compared with normal blood pressure.

The researchers concluded that in this analysis of US adults, the estimated prevalence of IDH was more common when defined by the 2017 ACC/AHA BP guideline compared with the JNC7 guideline. However, IDH was not significantly associated with increased risk for cardiovascular outcomes.

The researchers say the findings cast doubt on the pathogenicity of isolated diastolic hypertension.

For further reference log on to: JAMA article