IDH Prevalence Found to Increase When Defined by 2017 vs 2003 Guideline

Isolated diastolic hypertension (IDH), as defined in a 2017 guideline by the American College of Cardiology (ACC)/American Heart Association (AHA) was found to be more prevalent compared with IDH defined according to a 2003 Joint National Committee (JNC7) recommendation, according to a study published in the Journal of the American Medical Association.

In 2017, the ACC/AHA revised the definition of hypertension, lowering the threshold for blood pressure (BP) from ≥140/90 mm Hg (per the 2003 JNC7 recommendation) to ≥130/80 mm Hg. This updated threshold for diastolic BP was based on expert opinion rather than trial data, and modified the definition of IDH.

In this cross-sectional analysis, data from the 2013-2016 National Health and Nutrition Examination Survey (NHANES; n=9590; mean baseline age, 49.6 years; 52.3% women) were examined to identify IDH prevalence. A longitudinal analysis of data from the 1990 to 1992 Atherosclerosis Risk in Communities study (ARIC; n=8703; mean baseline age, 56 years; 57.2% women) was conducted to evaluate the prognostic implications of IDH. Findings from the longitudinal analysis were validated externally using data from the 1988-1994 NHANES III, 1999-2014 NHANES, and 1989 Give Us a Clue to Cancer and Heart Disease (CLUE) II studies.

The primary exposures were IDH according to the 2017 ACC/AHA criteria (systolic BP <130 mm Hg with diastolic BP ≥80 mm Hg) and according to the 2003 JNC7 definition (systolic BP <140 mm Hg with diastolic BP ≥90 mm Hg). The primary cross-sectional outcomes were weighted prevalence estimates for IDH and IDH-based BP pharmacotherapy recommendations (using the 2017 ACC/AHA guidelines). Outcomes of the primary longitudinal analysis were the incidence risks for atherosclerotic CV disease (ASCVD), chronic kidney disease (CKD), and heart failure (HF).

The estimated IDH prevalence in the NHANES cohort was 6.5% and 1.3% using the 2017 ACC/AHA and 2003 JNC7 definitions, respectively  (absolute difference, 5.2%; 95% CI, 4.7%-5.7%). A total of 0.6% of patients newly diagnosed with IDH (using the 2017 ACC/AHA definition) were estimated to also qualify for recommended BP pharmacotherapy (95% CI, 0.5%-0.6%).

When comparing participants with IDH (according to the 2017 ACC/AHA definition) from the ARIC study with normotensive participants, no association was identified between incident IDH and incident ASCVD (n=1386 events; mean follow-up, 25.2 years; hazard ratio [HR], 1.06; 95% CI, 0.89-1.26), CKD (n=2433 events; HR, 0.98; 95% CI, 0.65-1.11), or HF (n=1396 events; HR, 0.91; 95% CI, 0.76-1.09). No associations were identified between IDH (as defined by the 2017 ACC/AHA guidelines) and CV mortality in the NHANES (n=1012 events; HR, 1.17; 95% CI, 0.87-1.56) or CLUE II (n=1497 events; HR, 1.02; 95% CI, 0.92-1.14) cohorts.

Study limitations include potential non-generalizability to younger populations, inclusion of individuals taking antihypertensive medications, questionable applicability of ARIC results to all races, and possible underpowering that may not identify mild associations.

 “IDH appears to be a distinct phenotype of BP that has no consistently significant association with either subclinical or clinical ASCVD,” noted the study authors.

Disclosures: This research was supported by National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases grants R01DK089174 and K24DK106414 to Dr Selvin. The Atherosclerosis Risk in Communities (ARIC) Study has been funded in whole or in part with federal funds from the National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, under contract Nos. HHSN268201700001I, HHSN268201700002I, HHSN268201700003I, HHSN268201700005I, and HHSN268201700004I.

Please see original article for conflict of interest declarations.

Reference

Mcevoy JW, Daya N, Rahman F, et al. Association of isolated diastolic hypertension as defined by the 2017 ACC/AHA blood pressure guideline with incident cardiovascular outcomes. JAMA. 2020;323(4):329-338. doi:10.1001/jama.2019.21402