Leucocyte count predicts cardiovascular risk in heart failure with preserved ejection fraction: insights from TOPCAT Americas

Immune profiling of murine cardiac leukocytes identifies triggering receptor expressed on myeloid cells 2 as a novel mediator of hypertensive heart failure

AIMS

Heart failure with preserved ejection fraction (HFpEF) is characterized by diastolic dysfunction, microvascular dysfunction, and myocardial fibrosis with recent evidence implicating the immune system in orchestrating cardiac remodelling.

METHODS AND RESULTS

Here, we show the mouse model of deoxycorticosterone acetate (DOCA)-salt hypertension induces key elements of HFpEF, including diastolic dysfunction, exercise intolerance, and pulmonary congestion in the setting of preserved ejection fraction. A modified single-cell sequencing approach, cellular indexing of transcriptomes and epitopes by sequencing, of cardiac immune cells reveals an altered abundance and transcriptional signature in multiple cell types, most notably cardiac macrophages. The DOCA-salt model results in differential expression of several known and novel genes in cardiac macrophages, including up-regulation of Trem2, which has been recently implicated in obesity and atherosclerosis. The role of Trem2 in hypertensive heart failure, however, is unknown. We found that mice with genetic deletion of Trem2 exhibit increased cardiac hypertrophy, diastolic dysfunction, renal injury, and decreased cardiac capillary density after DOCA-salt treatment compared to wild-type controls. Moreover, Trem2-deficient macrophages have impaired expression of pro-angiogenic gene programmes and increased expression of pro-inflammatory cytokines. Furthermore, we found that plasma levels of soluble TREM2 are elevated in DOCA-salt treated mice and humans with heart failure.

CONCLUSIONS

Together, our data provide an atlas of immunological alterations that can lead to improved diagnostic and therapeutic strategies for HFpEF. We provide our dataset in an easy to explore and freely accessible web application making it a useful resource for the community. Finally, our results suggest a novel cardioprotective role for Trem2 in hypertensive heart failure.

Platelet, Neutrophil and Lymphocyte Quantitative Abnormalities in Patients with Heart Failure: A Retrospective Study

Background

Heart failure pathophysiology and its clinical symptoms are characterized by inflammation. Elevated levels of leukocyte subpopulations are a well-known indicator of inflammation and play a predictive role in determining the prognosis of patients with cardiovascular diseases. Besides, platelets are essential mediators of inflammation, especially when they interact with leukocytes. Platelet synthesis, activation, and function are all impacted by heart failure. Thus, the study was aimed at determining the magnitude of platelet, neutrophil, and lymphocyte abnormalities in patients with heart failure.

Methods

A retrospective cross-sectional study was conducted from June to July 2022 at the University of Gondar comprehensive specialized hospital. A total of 245 medical records of heart failure patients were included. Data regarding socio-demographic, clinical, and some hematological and biochemical parameters were collected from medical records. Data was entered into Epi-Data 4.6.0.2 and then exported to Stata 11.0 statistical software for analysis. A binary logistic regression analysis with its odds ratio was calculated to identify factors associated with the outcome variables. P-value <0.05 was considered statistically significant.

Results

The most frequent leukocyte abnormality among adults with heart failure was neutrophilia, which was detected in 17.55% (95% CI: 13.26-22.87). Besides, lymphocytosis was observed in 10.20% (95% CI: 6.97-14.70) of patients. The magnitude of thrombocytopenia and thrombocytosis among patients with heart failure was 12.24% (95% CI: 8.67-17.01%) and 2.86% (95% CI: 1.36-5.90%), respectively. Only being female was significantly associated with neutrophilia in patients with heart failure (AOR = 2.33; 95% CI: 1.05-5.16). However, none of the variables were significantly associated with platelet and lymphocyte abnormalities.

Conclusion

Neutrophilia, lymphocytosis, and thrombocytopenia are the common leukocyte and platelet abnormalities in heart failure patients. Therefore, early detection and management of the underlying causes of those abnormalities may be important to improve patients' outcomes and prevent further complications.

Targeting efficacy of spironolactone in patients with heart failure with preserved ejection fraction: the TOPCAT study

AIMS

We aimed to explore the heterogeneous treatment effects (HTEs) for spironolactone treatment in patients with Heart failure with preserved ejection fraction (HFpEF) and examine the efficacy and safety of spironolactone medication, ensuring a better individualized therapy.

METHODS AND RESULTS

We used the causal forest algorithm to discover the heterogeneous treatment effects (HTEs) from patients in the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial. Cox regressions were performed to assess the hazard ratios (HRs) of spironolactone medication for cardiovascular death and drug discontinuation in each group. The causal forest model revealed three representative covariates and participants were partitioned into four subgroups which were Group 1 (baseline BMI ≤ 31.71 kg/m² and baseline ALP ≤ 80 U/L, n = 759); Group 2 (BMI ≤ 31.71 kg/m² and ALP > 80 U/L, n = 1088); Group 3 (BMI > 31.71 kg/m² , and WBC ≤ 6.6 cells/μL, n = 633); Group 4 (BMI > 31.71 kg/m² and WBC > 6.6 cells/μL, n = 832), respectively. In the four subgroups, spironolactone therapy reduced the risk of cardiovascular death in high-risk group (Group 4) with both high BMI and WBC count (HR: 0.76; 95% CI 0.58 to 0.99; P = 0.045) but increased the risk in low-risk group (Group 1) with both low BMI and ALP (HR: 1.45; 95% CI 1.02 to 2.07; P = 0.041; P for interaction = 0.020) but showed similar risk of drug discontinuation (P for interaction = 0.498).

CONCLUSION

Our study manifested the HTEs of spironolactone in patients with HFpEF. Spironolactone treatment in HFpEF patients is feasible and effective in patients with high BMI and WBC while harmful in patients with low BMI and ALP. Machine learning model could be meaningful for improved categorization of patients with HFpEF, ensuring a better individualized therapy in the clinical setting.

Leukocyte count and the risk of adverse outcomes in patients with HFpEF

Background

Inflammation is a key feature of heart failure including HFpEF. The leukocyte count is a marker of inflammation that is widely used in clinical practice. However, there is little available evidence for the relationship between leukocyte count and the outcomes of HFpEF.

Methods

We analyzed data from the TOPCAT (Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist) trial. The primary outcome was all-cause mortality, the secondary outcome was composite cardiovascular events and hospitalization for heart failure. Multivariable Cox proportional hazard models were used to compare the risk profiles of patients with leukocyte quartiles, subgroup study divided by sex was also analyzed.

Results

The present study included 2898 patients with HFpEF.429 deaths, 671 composite cardiovascular events and 386 hospitalization for heart failure occurred during a mean 3.4 years follow-up. The association between leukocyte count and adverse outcomes followed a U-shaped curve. After multivariable adjustment, the patients with the lowest leukocyte count (Q1) and the highest leukocyte count (Q4) faced higher risk of all-cause death(Q1 vs. Q2, adjusted HR: 1.439; 95% CI: 1.060–1.953, p = 0.020; Q4 vs. Q2, adjusted HR, 1.901; 95%CI: 1.424–2.539, p < 0.001). The subgroup analysis showed a consistent result in female but not male patients.

Conclusions

The association between leukocyte count and risk of adverse outcomes followed a U-shaped curve. Both higher and lower leukocyte count are associated with worse outcomes in patients with HFpEF, which may be attributed to the two sides of inflammation in cardiac remodeling.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02142-y.

Relative Predictive Value of Circulating Immune Markers in US Adults Without Cardiovascular Disease: Implications for Risk Reclassification

OBJECTIVE

To investigate the relative predictive value of circulating immune cell markers for cardiovascular mortality in ambulatory adults without cardiovascular disease.

METHODS

We analyzed data of participants enrolled in the National Health and Nutrition Examination Survey from January 1, 1999, to December 31, 2010, with the total leukocyte count within a normal range (4000-11,000 cells/μL [to convert to cells ×10⁹/L, multiply by 0.001]) and without cardiovascular disease. The relative predictive value of circulating immune cell markers measured at enrollment-including total leukocyte count, absolute neutrophil count, absolute lymphocyte count, absolute monocyte count, monocyte-lymphocyte ratio (MLR), neutrophil-lymphocyte ratio, and C-reactive protein-for cardiovascular mortality was evaluated. The marker with the best predictive value was added to the 10-year atherosclerotic cardiovascular disease (ASCVD) risk score to estimate net risk reclassification indices for 10-year cardiovascular mortality.

RESULTS

Among 21,599 participants eligible for this analysis, the median age was 47 years (interquartile range, 34-63 years); 10,651 (49.2%) participants were women, and 10,713 (49.5%) were self-reported non-Hispanic white. During a median follow-up of 9.6 years (interquartile range, 6.8-13.1 years), there were 627 cardiovascular deaths. MLR had the best predictive value for cardiovascular mortality. The addition of elevated MLR (≥0.3) to the 10-year ASCVD risk score improved the classification by 2.7%±1.4% (P=.04). Elevated MLR had better predictive value than C-reactive protein and several components of the 10-year ASCVD risk score.

CONCLUSION

Among ambulatory US adults without preexisting cardiovascular disease, we found that MLR had the best predictive value for cardiovascular mortality among circulating immune markers. The addition of MLR to the 10-year risk score significantly improved the risk classification of participants.

The impact of platelet indices on clinical outcome in heart failure: results from the MyoVasc study

Aims

Platelet indices have been associated with traditional cardiovascular risk factors, cardiovascular diseases and all‐cause mortality. This study aimed to investigate the role of platelet count, mean platelet volume (MPV) and platelet‐to‐leukocyte ratio, including platelet‐to‐monocyte and platelet‐to‐lymphocyte ratio with cardiac function, heart failure (HF) phenotypes and clinical outcome, worsening of HF.

Methods and results

Univariate and multivariable linear and Cox regression analyses were used to investigate the associations between platelet indices, cardiac function and worsening of HF in 3250 subjects enrolled in the MyoVasc study. Higher MPV, lower platelet count, lower platelet‐to‐leukocyte and platelet‐to‐monocyte ratios have been associated with reduced left ventricular ejection fraction (beta estimate [β]_{MPV [fL]} = −0.05 [−0.09; −0.02], β_{platelet count (× 10/L)}⁹ = 3.4 [1.2; 5.6], β_{platelet‐to‐leukocyte ratio} = 1.4 [1.1; 1.8], β_{platelet‐to‐monocyte ratio} = 28 [20; 36]) and increased E/E' ratio (β _{MPV [fL]} = 0.04 [0.003; 0.07], β_{platelet count (× 10/L)}⁹ = −3.1 [−5.3; −0.92], β_{platelet‐to‐leukocyte ratio} = −0.83 [−1.2; −0.46], β_{platelet‐to‐monocyte ratio} = −20 [−28; −12]), independent of age and sex. Cox regression demonstrated an increased risk for worsening of HF in subjects with MPV > 75th percentile (hazard ratio [HR] = 1.47 [1.16; 1.87]), platelet count < 25th percentile (HR = 1.36 [1.07; 1.74]), platelet‐to‐leukocyte < 25th percentile (HR = 1.53 [1.20; 1.95]), platelet‐to‐monocyte < 25th percentile (HR = 1.38 [1.08; 1.77]) and platelet‐to‐lymphocyte > 75th percentile (HR = 1.50 [1.17; 1.93]) ratios, independent of potential confounders. MPV > 75th percentile and platelet count < 25th percentile were strongly related to outcome in HFpEF vs. HFrEF (P for difference = 0.040). Platelet‐to‐leukocyte ratios were associated with worse outcome in both HF phenotypes, without a significant difference between HFpEF and HFrEF.

Conclusions

Platelet indices are linked with worse cardiac function and adverse clinical outcome, independent of subjects' underlying cardiovascular profile. This study emphasizes their important value to provide additional information on pathophysiology and risk stratification in HF syndrome.

Risk Stratification and Efficacy of Spironolactone in Patients with Heart Failure with Preserved Ejection Fraction: Secondary Analysis of the TOPCAT Randomized Clinical Trial

PURPOSE

We aimed to develop a simple risk score for patients with HFpEF and assessed the efficacy of spironolactone across baseline risk.

METHODS

We developed risk stratification scheme for cardiovascular death in placebo arm of the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist trial (TOPCAT). We screened candidate risk indicators and determined strong risk predictors using COX regression. The absolute risk reduction (ARR) in cardiovascular death with spironolactone was evaluated across baseline risk groups. COX regressions were performed to assess the hazard ratios (HRs) of spironolactone therapy for cardiovascular death and drug discontinuation in each risk category.

RESULTS

A simple risk score scheme was constructed based on five risk indicators weighted by estimates from the model, including age, diastolic blood pressure, renal dysfunction, white blood cell, and left ventricular ejection fraction. The risk score scheme showed good discrimination in placebo cohort (C index=0.70). ARR with spironolactone therapy was observed only in patients at very high risk (7.9%). Spironolactone therapy significantly reduced the risk of cardiovascular death in the very high-risk group (HR: 0.57; 95%CI, 0.39-0.84; P =0.005 and P for interaction 0.03) but showed similar risk of drug discontinuation across risk categories (P for interaction=0.928).

CONCLUSION

This simple risk score stratifies patients with HFpEF by their baseline risk of cardiovascular death. Patients at very high risk derive great benefits from spironolactone therapy. This easy-to-use risk score provides a practical tool that can facilitate risk stratification and tailoring therapy for those who benefit most from spironolactone.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00094302.

Leucocyte count predicts cardiovascular risk in heart failure with preserved ejection fraction: insights from TOPCAT Americas

AIMS

Prior evidence has implicated leucocyte expansion in several cardiovascular disorders, including heart failure (HF) with reduced ejection fraction (rEF). However, the prognostic importance of leucocyte count in HF with preserved EF (HFpEF) remains largely unexplored.

METHODS AND RESULTS

The Americas cohort of the treatment of preserved cardiac function heart failure with an aldosterone antagonist (TOPCAT-Americas) was used to evaluate the association between total leucocyte count and clinical outcomes in HFpEF. The primary outcome was a composite of aborted cardiac arrest, cardiovascular mortality, or hospitalization for HF. Secondary outcomes were hospitalization for HF, aborted cardiac arrest, stroke, non-fatal myocardial infarction (MI), cardiovascular mortality, non-cardiovascular mortality, and all-cause mortality. Survival models were used to identify the risk of the primary and secondary outcomes in those with leucocyte count above the median (7100 cells/μL), as compared to those with leucocyte count below the median, during the follow-up period. A total of 1746 (out of 1767; 99%) patients from TOPCAT-Americas were available for the analyses with a median follow up of 2.4 (25th to 75th percentile 1.4-3.9) years. Patients with leucocyte count >7100 cells/μL were 36% more likely to experience the primary endpoint compared to those with ≤7100 cells/μL (hazard ratio: 1.36, 95% confidence interval: 1.14-1.61). This association remained significant after extensive adjustment for potential confounders (hazard ratio: 1.27, 95% confidence interval: 1.06-1.52). We also observed a greater incidence of HF hospitalization and non-fatal MI in patients with higher leucocyte count. These associations remained robust on sensitivity analyses, suggesting a low probability of confounding. Exploratory analyses suggested that both higher leucocyte count (integrating the combined influence of both myeloid and lymphoid immune cells) and augmented platelet count (as a surrogate for myeloid immune cell expansion) in the same model were associated with the primary outcome (both P < 0.05).

CONCLUSIONS

Leucocyte count >7100 cells/μL was independently associated with adverse clinical outcomes in HFpEF patients from TOPCAT-Americas. These results were primarily driven by the HF hospitalization outcome but were also accompanied by an excess of non-fatal MI. Further research is needed to define the mechanisms underlying our findings and their prognostic implications.