Association of Blood Pressure Classification in Korean Young Adults According to the 2017 American College of Cardiology/American Heart Association Guidelines With Subsequent Cardiovascular Disease Events

Abstract

Importance: Among young adults, the association of the 2017 American College of Cardiology/American Heart Association (ACC/AHA) High Blood Pressure Clinical Practice Guidelines with risk of cardiovascular disease (CVD) later in life is uncertain.

Objective: To determine the association of blood pressure categories before age 40 years with risk of CVD later in life.

Design, setting, and participants: This population-based cohort study from the Korean National Health Insurance Service consisted of 2 488 101 adults aged 20 through 39 years with blood pressure measurements taken twice from 2002 through 2005. Starting from January 1, 2006, participants were followed up until the date of CVD diagnosis, death, or December 31, 2015.

Exposures: Participants were categorized by blood pressure readings: normal (systolic, <120 mm Hg; diastolic, <80 mm Hg), elevated (sytolic, 120-129 mm Hg; diastolic, <80 mm Hg), stage 1 hypertension (systolic, 130-139 mm Hg; diastolic, 80-89 mm Hg), and stage 2 hypertension (systolic, ≥140 mm Hg; diastolic, ≥90 mm Hg).

Main outcomes and measures: The primary outcome was CVD defined as 2 or more days of hospitalization due to CVD or death due to CVD. The secondary outcomes were coronary heart disease (CHD) and stroke.

Results: The study population consisted of 2 488 101 participants (median age, 31 years [interquartile range, 27-36 years], 789 870 women [31.7%]). A total of 44 813 CVD events were observed during a median follow-up duration of 10 years. Men with baseline stage 1 hypertension compared with those with normal blood pressure had higher risk of CVD (incidence, 215 vs 164 per 100 000 person-years; difference, 51 per 100 000 person-years [95% CI, 48-55]; adjusted hazard ratio [HR], 1.25 [95% CI, 1.21-1.28]), CHD (incidence, 134 vs 103 per 100 000 person-years; difference, 31 per 100 000 person-years [95% CI, 28-33]; adjusted HR, 1.23 [95% CI, 1.19-1.27]), and stroke (incidence, 90 vs 67 per 100 000 person-years; difference, 23 per 100 000 person-years [95% CI, 21-26]; adjusted HR, 1.30 [95% CI, 1.25-1.36]). Women with baseline stage 1 hypertension compared with those with normal blood pressure had increased risk of CVD (incidence, 131 vs 91 per 100 000 person-years; difference, 40 per 100 000 person-years [95% CI, 35-45]; adjusted HR, 1.27 [95% CI, 1.21-1.34]), CHD (incidence, 56 vs 42 per 100 000 person-years; difference, 14 per 100 000 person-years [95% CI, 11-18]; adjusted HR, 1.16 [95% CI, 1.08-1.25]), and stroke (incidence, 79 vs 51 per 100 000 person-years; difference, 28 per 100 000 person-years [95% CI, 24-32]; adjusted HR [1.37, 95% CI, 1.29-1.46]). Results for state 2 hypertension were consistent.

Conclusions and relevance: Among Korean young adults, stage 1 and stage 2 hypertension, compared with normal blood pressure, were associated with increased risk of subsequent cardiovascular disease events. Young adults with hypertension, defined by the 2017 ACC/AHA criteria, may be at increased risk of cardiovascular disease.

Figure 1.. Flow Diagram of the Study Population

Figure 2.. Hazard Ratios for Cardiovascular Disease According to Index Blood Pressure Among Young Adults With and Without Stratification According to Antihypertensive Medication Prescription Within the First 5 Years of Follow-up

Solid lines indicate hazard ratios and shaded areas indicate 95% CIs using restricted cubic spline regression. Without antihypertensive medication indicates that patients had not been prescribed antihypertensive medication within the first 5 years of follow-up; with antihypertensive medication indicates that they were prescribed antihypertensive medication within the first 5 years of follow-up. Restricted cubic splines were constructed with 4 knots placed at the fifth, 35th, 65th, and 95th percentiles. Hazard ratios were calculated by Cox proportional hazards regression analysis after adjustments for age, household income, physical activity, smoking, alcohol consumption, body mass index, fasting serum glucose and total cholesterol levels, and Charlson comorbidity index.