Hypertension Subtype Defined by the 2017 ACC/AHA Blood Pressure Guidelines and Risk of Cardiovascular Disease: A Large Prospective Cohort Study

IMPORTANCEThe 2017 American College of Cardiology/American Heart Association (ACC/AHA) blood pressure (BP) guidelines lowered the hypertension threshold from a systolic blood pressure/diastolic blood pressure level of [&ge;]140/90 mm Hg to [&ge;]130/80 mm Hg. The cardiovascular impact of isolated systolic hypertension (ISH) and isolated diastolic hypertension (IDH) under the new definition remains unclear. OBJECTIVETo examine the associations of ISH and IDH defined by the 2017 ACC/AHA guidelines with risk of cardiovascular disease (CVD) among the UK population. DESIGN, SETTING, AND PARTICIPANTSWe used data from the UK Biobank study, which is a prospective population-based cohort study. Participants were categorized into 5 groups: normal BP, normal high BP, ISH, IDH and systolic and diastolic hypertension (SDH). MAIN OUTCOMES AND MEASURESThe primary endpoint for this study was the composite of nonfatal myocardial infarction (MI), nonfatal ischemic stroke (IS), nonfatal haemorrhagic stroke (HS) and CVD death. We also explored the results for the above mentioned CVD outcomes separately. Baseline BP measurements were obtained twice after the participant had been at rest for at least 5 minutes in a seated position. RESULTSWe included 470,625 participants who were free of CVD at baseline and had available data on BP measures. During a median follow-up of 8.1 years, 13,157 CVD events were recorded, including 6,865 nonfatal MI, 3,415 nonfatal ISs, 1,118 nonfatal HSs, and 2,971 CVD deaths. According to the hypertension threshold of [&ge;]130/80 mm Hg by the ACC/AHA guidelines, both ISH (HR 1.35, 95% CI 1.24-1.46) and IDH (HR 1.22, 95% CI 1.11-1.36) were significantly associated with a higher overall CVD risk as compared with normal BP. ISH was associated with most CVD risk, except for IS, while the excess CVD risk associated with IDH appeared to be driven mainly by MI. We found heterogeneity by sex and age regarding the effects of IDH on overall CVD risk, with significant associations in younger adults (age < 60 years) and women and null associations in men and older adults (age [&ge;]60 years). CONCLUSIONS AND RELEVANCEBoth ISH and IDH were associated with an increased risk of CVD among the UK population according to the ACC/AHA BP guidelines. Further research is needed to identify participants with IDH who have a particularly risk for developing CVD. Key points QuestionWhat are the associations of isolated systolic hypertension (ISH) and isolated diastolic hypertension (IDH) by the 2017 ACC/AHA guidelines with CVD risk among the UK population? FindingsIn this prospective population-based cohort study of 470,625 UK participants, we found that compared with normotensive participants, those with ISH or IDH both had higher risk of overall CVD outcome. However, for participants with IDH, most CVD risk was driven by myocardial infarction and significant associations were observed in younger adults (age < 60 years) and women only. MeaningOur results indicate that by using the lower hypertension threshold by the 2017 ACC/AHA guidelines, both ISH and IDH were linked to a higher risk of CVD. Yet, results varied across age and sex for IDH, suggesting that more research is needed to identify participants with IDH who are at especially greater risk for developing CVD.