Blood Pressure Control Not Well-Met Among Diverse Heart Failure Population
SEPTEMBER 14, 2019
In a study presented at the Heart Failure Society of America (HFSA) 2019 Scientific Sessions in Philadelphia, PA, a team of investigators from Northwestern University Feinberg School of Medicine reported findings no significant associations between BP control and cardiovascular mortality in treated and untreated patients with HF.
Led by Leah Rethy of the Division of Cardiology, investigators sought to define rates of BP control among a nationally representative HF population by race/ethnicity subgroups, stratified by patient hypertension treatment status.
Rethy and colleagues also sought the association between BP control and cardiovascular mortality among patients with ambulatory HF.
“We know that, in the general population, treatment and controlled blood pressure does vary by race,” Rethy told MD Magazine®. “And we wanted to see if the same kind of thing would pan out in heart failure population.”
Investigators used data from the National Health and Nutrition Examination Survey (NHANES), an annual series of studies that combines results of the US population’s medical interviews and physical examinations. Their population included non-Hispanic white, black, and Mexican American adults ≥20 years old with HF (n= 1098).
Patients had no missing values for variables of interest, and pregnant patients were excluded from assessment.
BP control, as set by the 2017 guidelines from the American Heart Association, American College of Cardiology, and the HFSA (AHA/ACC/HFSA)—and based on the results of the SPRINT trial, which established significance of BP control in the prevention of HF—was defined as <130/80 mmHg.
The team calculated prevalence ratios for BP control in black versus non-Hispanic white, and Mexican Americans versus non-Hispanic white HF patients, with stratification per treatment status. Ratios were adjusted for age, sex, and socioeconomic status factors.
Overall, mean patient age was 66.5 years. Mean body mass index (BMI) was 31.6 kg/m2. Patients had a mean systolic BP of 128.8. Both black (132.7) and Mexican American (131.4) patients had a mean systolic BP greater than 130.
Investigators found the low rates of BP control were comparable to those published on the general population, though the prevalence rate of BP control was lower among black adults compared to non-Hispanic white adults. There were no observed significant differences between the rates of Mexican Americans and non-Hispanic whites.
Overall, the prevalence rate of BP control among hypertension-treated patients with HF (48.7%) was not significantly different from the rate among untreated patients (51.4%).
Over the mean follow-up of 5.4 years, investigators found no significant association between BP control and cardiovascular mortality for treated patients (HR 0.80; 95% CI, 0.51 – 1.27). But cardiovascular mortality did decrease at <140/90 mmHg BP among patients not on treatment (HR 0.44; 95% CI, 0.21 – 0.94).
Rethy and colleagues concluded that, due to the high rates of observed elevated BP, the notable disparities of BP control among races/ethnicities, and the limited data available on optimal BP targets, the next clinical pursuit should be randomized controlled trials which focus on identifying optimal BP targets among patients with HF.
“At least what we were able to do—looking at outcomes from this large data set, we didn’t see an increased hazard of death, but we also didn’t see any improvement,” Rethy said. “So we didn’t see any sign we’re hurting people by keeping them at a lower (BP) number, but there are limitations to this kind of analysis.”
The study, “Disparities in Blood Pressure Treatment and Control in Ambulatory Heart Failure Patients: 1999-2016,” was presented at HFSA 2019.