Under-Enrollment of Obese Heart Failure with Preserved Ejection Fraction Patients in Major HFpEF Clinical Trials

Low Natriuretic Peptide Levels and Outcomes in Patients With Heart Failure and Preserved Ejection Fraction

BACKGROUND

Although some patients with heart failure (HF) with mildly reduced/preserved ejection fraction have low natriuretic peptide levels, there are no large-scale systematic studies of how common these individuals are or what happens to them.

OBJECTIVES

The purpose of this study was to examine the proportion of patients in the I-PRESERVE (Irbesartan in Heart Failure with Preserved Ejection Fraction) trial with an N-terminal pro-B-type natriuretic peptide (NT-proBNP) level <125 pg/mL, their clinical characteristics, and outcomes.

METHODS

I- PRESERVE enrolled patients with symptomatic HF and a LVEF ≥45% but who did not have NT-proBNP or body mass index inclusion/exclusion criteria. Baseline NT-proBNP was measured after enrollment but not reported to investigators. The primary outcome in this analysis was the composite of cardiovascular death or HF hospitalization.

RESULTS

Overall, 808 of 3,480 patients (23.2%) had NT-proBNP <125 pg/mL. Patients with a low NT-proBNP were younger (68.6 years vs 72.6 years; P < 0.001), were less often men (36.1% vs 40.9%; P = 0.015), and had a higher body mass index (48.4% vs 38.7% obese; P < 0.001) than those with a higher NT-proBNP level. Patients with a low NT-proBNP had less atrial fibrillation (8.5% vs 35.1%; P < 0.001), myocardial infarction, diabetes, chronic obstructive pulmonary disease, and anemia but better kidney function. Patients with a lower NT-proBNP level had less marked echocardiographic abnormalities and were less likely to experience cardiovascular death or HF hospitalization; adjusted HR: 0.35 (95% CI: 0.27-0.46; P < 0.001). However, health status was similarly impaired in patients with lower and higher NT-proBNP levels (median Minnesota Living with Heart Failure Questionnaire 43 vs 43; P = 0.95).

CONCLUSIONS

Almost one-quarter of patients with HF with mildly reduced/preserved ejection fraction had a low NT-proBNP level. Although these patients have a favorable prognosis, compared to those with a high NT-proBNP level, they have similarly impaired health status which should be a target for treatment. (Irbesartan in Heart Failure With Preserved Systolic Function [I- PRESERVE]; NCT00095238).

Implications of trial eligibility in patients with heart failure with mildly reduced or preserved ejection fraction

AIMS

Clinical trials in heart failure with mildly reduced or preserved ejection fraction (HFmrEF/HFpEF) commonly have detailed eligibility criteria. This may contribute to challenges with efficient enrolment and questions regarding the generalizability of trial findings.

METHODS AND RESULTS

Patients with HFmrEF/HFpEF from a large US healthcare system were identified through a computable phenotype applied in linked imaging and electronic health record databases. We evaluated shared eligibility criteria from five recent/ongoing HFmrEF/HFpEF trials (PARAGON-HF, EMPEROR-Preserved, DELIVER, FINE-ARTS, and SPIRRIT-HFpEF) and compared clinical and echocardiographic features as well as outcomes between trial-eligible and trial-ineligible patients. Among 5552 patients with HFpEF/HFmrEF, 792 (14%) were eligible for trial consideration, having met all criteria assessed. Causes of ineligibility included lack of recent loop diuretics (37%), significant pulmonary disease (24%), reduced estimated glomerular filtration rate (17%), recent stroke/transient ischaemic attack (13%), or low natriuretic peptides (12%); 53% of ineligible patients had >1 reason for exclusion. Compared with eligible patients, ineligible patients were younger (age 71 vs. 75 years, P < 0.001) with higher rates of coronary artery disease (66% vs. 59%, P < 0.001) and peripheral vascular disease (40% vs. 33%, P < 0.001), but less mitral regurgitation, lower E/e' ratio, and smaller left atrial sizes. Both eligible and ineligible patients demonstrated high rates of structural heart disease consistent with HFpEF [elevated left atrial size or left ventricular (LV) hypertrophy/increased LV mass], although this was slightly higher among eligible patients (95% vs. 92%, P = 0.001). The two cohorts demonstrated similar LV global longitudinal strain along with a similar prevalence of atrial fibrillation/flutter, hypertension, and obesity. Ineligible patients had similar all-cause mortality (33% vs. 33% at 3 years) to those eligible but lower rates of heart failure hospitalization (20% vs. 28% at 3 years, P < 0.001).

CONCLUSIONS

Among patients with HFmrEF/HFpEF from a large health system, approximately one in seven were eligible for major trials based on key criteria applied through a clinical computable phenotype. These findings highlight the large proportion of patients with HFmrEF/HFpEF ineligible for contemporary trials for whom the generalizability of trial findings may be questioned and further investigation would be beneficial.

Obesity, Cardiorenal Comorbidities, and Risk of Hospitalization in Patients With Heart Failure With Preserved Ejection Fraction

OBJECTIVE

To compare clinical features of patients with obesity-related heart failure (HF) with preserved ejection fraction (HFpEF) with those of patients with similar body mass index (BMI) but no HF and to examine the association between degree of obesity and risk for hospitalizations.

METHODS

This was a retrospective analysis of 22,750 adults from a large US electronic health care data set (January 1, 2012, through July 31, 2019), including 4975 with HFpEF. Baseline characteristics were compared between patients with HFpEF and a control group matched on BMI, age, sex, and year of BMI record. Risk of first hospitalization was analyzed in the HFpEF sample with negative binomial and Cox proportional hazards models, adjusted for baseline comorbidities.

RESULTS

Compared with controls without HF matched on BMI, age, sex, and year of BMI record, patients with HFpEF displayed worse kidney function, greater estimated plasma volume, and more cardiovascular comorbidities. Within the HFpEF cohort, patients with higher degree of obesity were younger and had fewer concomitant cardiovascular comorbidities than those with lower degree of obesity. The mean number of HF-related hospitalizations increased with higher degree of obesity (9.6 to 15.7/100 patient-years; P=.002), but higher degree of obesity was not associated with increased risk of non-HF-related hospitalizations.

CONCLUSION

Among persons with obesity, increasing cardiorenal dysfunction and volume overload differentiate those with HFpEF. Among persons with established HFpEF, those with higher degree of obesity are younger and have fewer cardiovascular comorbidities but display a unique increased risk of HF-related hospitalizations, even as risk for other hospitalizations is not different.