For people with hypertension and left ventricular hypertrophy (LVH), getting their blood pressure down as low as possible could help reduce their risk for cardiovascular disease (CVD) events, new research suggests.
In a nationwide cohort study of Korean adults with LVH who were followed for more than 11 years, patients with a systolic blood pressure (SBP) > 140 mm Hg and diastolic blood pressure (DBP) of > 90 mm Hg while on antihypertensive therapy had a 30% increased risk of having a cardiovascular event compared with those with lower (SBP < 130 mm Hg, DBP < 80 mm Hg) blood pressure.
The study is published online October 4 in the Journal of the American College of Cardiology.
In this analysis, investigators led by Hyeok-Hee Lee, MD, Yonsei University College of Medicine, Seoul, Korea, aimed to see whether lower blood pressures were associated with lower cardiovascular event rates in a real-world cohort of hypertensive patients with LVH.
They identified 95,545 participants aged 40 to 79 years who were taking antihypertensive medication and had LVH on baseline electrocardiography.
Over a median follow-up of 11.5 years, 12,035 new CVD events were recorded. Primary outcome events were defined as the first hospitalization for myocardial infarction, stroke, heart failure, or a CVD-related death recorded through December 31, 2019.
The authors report that the number of CVD events rose along with systolic and diastolic blood pressures.
Table. CVD Events by BP Level
|BP Level||CVD Events (n)|
|SBP < 120 mm Hg||442|
|SBP 120 – 129 mm Hg||1709|
|SBP 130 – 139 mm Hg||3406|
|SBP ≥ 140 mm Hg||6478|
|DBP < 70 mm Hg||353|
|DBP 70 – 79 mm Hg||2519|
|DBP 80 – 89 mm Hg||5577|
|DBP > 90 mm Hg||3586|
Overall, in this population, 77.4% of patients on antihypertensive therapy had SBP > 130 mm Hg, and 76.5% of patients had DBP > 80 mm Hg.
Patients with SBP > 140 mm Hg and DBP > 90 mm Hg had a 30% higher rate of cardiovascular events compared with patients in the lower blood pressure group.
Compared with patients in the lower blood pressure group (ie, SBP 120 – 129 mm Hg and DBP 70 – 79 mm Hg), the adjusted hazard ratio for those with SBP > 140 mm Hg and DBP > 90 mm Hg was 1.31 (95% confidence interval [CI], 1.24 – 1.38), and for DBP > 90 mm Hg, the adjusted hazard ratio was 1.30 (95% CI, 1.24 – 1.37).
However, blood pressure levels < 120/< 70 mm Hg were not associated with additional reductions in CVD risk.
In addition, lower SBP below 130 mm Hg was associated with hypotension, syncope, electrolyte abnormality, or acute kidney injury. Lower DBP below 80 mm Hg was not significantly associated with adverse events.
“Further randomized trials are warranted to establish optimal BP-lowering strategies for patients with hypertension and LVH,” the investigators conclude.
“The findings from Lee et al provide real-world evidence that in high-risk patients with hypertension and LVH, achieving lower SBP and DBP is associated with an overall reduction in cardiovascular events,” S. Andrew McCullough, MD, Weill Cornell Medicine, New York, New York, et al, write in an accompanying comment.
“This study highlights a lot of different important points,” McCullough told theheart.org | Medscape Cardiology in an interview. “Perhaps the most important is that there is a lot of controversy on how to take care of patients with high blood pressure and certain undefined subgroups, and people use that controversy as an excuse for substandard care,” he said.
“In general, patients who are elderly, or who are not candidates for clinical trials, if their blood pressure is elevated in the clinic, in the higher 130s to 140s, oftentimes, it’s easier for the busy clinician to disregard that and not optimize their antihypertensive therapy,” McCullough said.
“The study expands the population to patients with left ventricular hypertrophy, a well-described marker of heart attack, heart failure, and cardiovascular death. Even in the higher-risk patients in this study, there seemed to be improvement in the rates of heart attack, heart failure hospitalization or cardiovascular death. It is not a randomized trial, but still the patients with systolic blood pressures less than 130 did substantially better,” he said.
The study was supported by the Korea Health Technology Research and Development Project, the Korea Health Industry Development Institute, the Ministry of Health and Welfare of South Korea, and the Republic of Korea. Lee and McCullough report no relevant financial relationships.