Differences in prevalence of hypertension subtypes according to the 2018 Korean Society of Hypertension and 2017 American College of Cardiology/American Heart Association guidelines: The Korean National Health and Nutrition Examination Survey, 2007–2017 (KNHANES IV-VII)

BACKGROUND: The significance of high systolic and diastolic blood pressure remains controversial. We assessed the differences in prevalence of hypertension and its subtypes according to the different hypertension diagnostic criteria embodied by the 2017 American College of Cardiology/American Heart Association (2017 ACC/AHA) and 2018 Korean Society of Hypertension (2018 KSH) guidelines. METHODS: We used the 2007–2017 Korea National Health and Nutrition Examination Survey (KNHANES) data to calculate guideline-specific hypertension prevalence among untreated, adult participants. By the 2017 ACC/AHA guideline, a mean SBP ≥130 mmHg, DBP ≥80 mmHg, or currently using antihypertensive medications were considered to have hypertension. Isolated diastolic hypertension (IDH) was defined as DBP ≥80 mmHg and SBP <130 mmHg, isolated systolic hypertension (ISH) as SBP ≥130 mmHg and DBP <80 mmHg, and systolic diastolic hypertension (SDH) as SBP ≥130 mmHg and DBP ≥80 mmHg. In a similar manner, by the 2018 KSH guideline, all hypertension and its subtype prevalence were calculated using the 140/90 mmHg cutoff. The two versions of all hypertension and its corresponding subtype prevalence were calculated among all study participants and separately by sex and age then compared via analysis of variance. RESULTS: The prevalence of all hypertension increased from 25.9% (95% confidence interval (CI) 25.4–26.5) defined by the 2018 KSH guideline to 46.3% (95% CI 45.6–46.9) classified by the 2017 ACC/AHA guideline. Such increase was primarily manifested through substantial increase in IDH prevalence, from 5.2% (95% CI 4.9–5.4) defined by the 2018 KSH guideline to 17.9% (95% CI 17.4–18.3) defined by the 2017 ACC/AHA guideline, and was most notably observed in young age groups, 30-49 years. ISH prevalence showed minimal differences. SDH prevalence moderately increased from 3.5% (95% CI 3.3–3.7) defined by the 2018 KSH guideline to 11.1% (95% CI 10.7–11.4) defined by the 2017 ACC/AHA guideline, achieved primarily among participants aged 50 years or above. CONCLUSIONS: Changes in each subtype prevalence made differential contribution to additionally classified hypertension cases by the 2017 ACC/AHA guideline. Future studies should investigate the diastolic-associated cardiovascular risks and benefits of its long-term primary prevention in the young population.