Marlene Busko
April 26, 2022
Using the 2021 Kidney Disease: Improving Global Outcomes (KDIGO) guideline target of systolic blood pressure (BP) < 120 mm Hg, 66% of adults with chronic kidney disease (CKD) would be eligible for BP lowering, according to a study from South Korea.
This represents an added > 10% of patients compared with two earlier guidelines, and these patients have a high risk of cardiovascular disease (CVD), Hyeok-Hee Lee, MD, Yonsei University College of Medicine, Seoul, South Korea, and colleagues report.
The study was published online April 25 in the Journal of the American College of Cardiology.
“New candidates for BP-lowering treatment per the 2021 KDIGO guideline account for a substantial proportion of the total CKD population and bear significantly high CVD risk,” the researchers conclude.
“Undoubtedly, a multipronged approach will be required to address the swelling number of people needing more intense treatment, especially against a background of falling rates of BP control in the general community,” Alexander G. Logan, MD, from Mount Sinai Hospital and the University of Toronto, Ontario, Canada, writes in an accompanying editorial.
“Let’s not forget hypertension is the number one killer today,” Valentin Fuster, MD, of Mount Sinai Hospital, New York City, who is editor-in-chief of the Journal of the American College of Cardiology, stressed in a podcast that accompanied the article.
“Only 50% of individuals know of their blood pressure, and from this, less than half are properly treated,” he said.
“Today the details of knowing blood pressure levels appear to dominate over the huge ignorance of not knowing about blood pressure at all. Let’s think more and more about this reality,” he urged.
Three Guidelines, Two Study Objectives
The researchers compared three guidelines:
- The 2021 KDIGO guidelines, with a target systolic BP of < 120 mm Hg (largely based on the SPRINT trial).
- The 2012 KDIGO guidelines, with a target BP of ≤ 130/80 mm Hg for patients with albuminuria and ≤ 140/90 mm Hg for patients without albuminuria.
- The 2017 American College of Cardiology/American Heart Association (ACC/AHA) BP guideline target of < 130/80 mm Hg.
The study had two objectives:
- To examine the proportions of concordance and discordance between the three guidelines among adults with CKD based on cross-sectional data from the Korea National Health and Nutrition Examination Survey (KNHANES).
- To evaluate the association of each concordance/discordance group with cardiovascular outcomes of patients in the Korean National Health Insurance Service (NHIS) database.
For the first objective, the researchers identified 1939 adults with CKD from the 2011-2014 survey cycles of KNHANES. Patients were a median age of 59 and 51% were men.
Comparison of the KDIGO 2021 versus 2012 BP targets showed that 50% of patients had BP above both targets; 16% had BP above the KDIGO 2021 target only; 4% had BP above the KDIGO 2012 target only; and 30% had BP control within both targets.
Comparison of the KDIGO 2021 versus 2017 ACC/AHA BP targets showed that 55% of patients had BP above both targets; 11% had BP above the KDIGO 2021 target only; 5% had BP above the 2017 ACC/AHA target only; and 29% had BP control within both targets.
For the second objective, using the NHIS database, researchers identified 412,167 adults with CKD who had routine health examinations during 2009 and 2010. The patients were a median age of 65 and 44% were men.
During a median follow-up of 10 years, the patients had 37,912 incident CVD events, defined as the first hospitalization for myocardial infarction, stroke, or heart failure, or death from CVD.
The adjusted risk of a composite CVD event was higher in patients with BP above the 2021 KDIGO target only (HR, 1.28) or above both the 2012 and 2021 KDIGO targets (HR, 1.52), compared to patients who had BP within both targets.
The adjusted risk of a composite CVD event was also higher in patients with BP above the 2021 KDIGO target only (HR, 1.18) or above both the 2021 KDIGO target and the 2017 ACC/AHA target (HR, 1.41), compared to patients who had BP within both targets.
Editorialist Highlights Three Study Aspects
Fuster noted three main points made by Logan.
First, the KDIGO 2021 guideline is based on office blood pressure, measured according to the procedure used in the 2017 ACC/AHA guideline. However, the SPRINT ambulatory BP ancillary study found that daytime ambulatory systolic BP was 6.8 mm Hg higher in the < 120 mm Hg group than clinic systolic BP that was measured with an automated BP device, mostly without study personnel.
Second, Logan notes that “not surprisingly, the investigators showed that the weighted proportion of adults with CKD eligible for BP lowering was highest (66.1%) according to 2021 KDIGO guideline” compared with the two earlier guidelines.
The findings by Lee and colleagues align with those of a study that used data from the 2015-2018 US NHANES to estimate the proportion of US adults with CKD eligible for BP lowering according to the 2021 KDIGO guidelines, Logan adds. The study found that 69% of US adults (roughly 24.5 million) should correct their BP.
Third, the study in South Korea showed a small percentage of patients (3% to 5% of the total) had elevated diastolic BP but controlled systolic BP (< 120 mm Hg) with no increased risk of CVD compared to a reference group of patients with well-controlled BP.
“There is a paucity of evidence examining the relationship between diastolic hypertension and outcomes independently from systolic BP level in CKD patients,” Logan writes. Similarly, Lee and colleagues identified this as an area for further research.
This work was supported by the Korea Health Technology R&D Project through the Korea Health Industry Development Institute funded by the Ministry of Health and Welfare, Republic of Korea. The authors and editorialist have reported no relevant financial relationships.
Leave a Reply