Elevated plasma sRAGE and IGFBP7 in heart failure decrease after heart transplantation in association with haemodynamics

Insulin-like growth factor binding protein-7 concentrations in chronic heart failure: Results from the EMPEROR programme

AIMS

Insulin-like growth factor binding protein-7 (IGFBP7) is a biomarker of tissue senescence with a role in cardio-renal pathophysiology. The role of IGFBP7 as a prognostic biomarker across the full ejection fraction (EF) spectrum of heart failure (HF) remains less well understood. We examined associations between IGFBP7 and risk of cardio-renal outcomes regardless of EF and the effect of empagliflozin treatment on IGFBP7 concentrations among individuals with HF.

METHODS AND RESULTS

IGFBP7 was measured in 1125 study participants from the EMPEROR-Reduced and EMPEROR-Preserved trials. Cox regression was used to study associations with outcomes. Study participants with IGFBP7 levels in the highest tertile had a higher-risk clinical profile. In Cox proportional hazards models adjusted for clinical variables, N-terminal pro-B-type natriuretic peptide and high-sensitivity cardiac troponin T, baseline IGFBP7 values in the highest tertile predicted an increased risk of HF hospitalization or cardiovascular death (hazard ratio [HR] 2.00, 95% confidence interval [CI] 1.28-3.10, p = 0.002, p for trend <0.001) and higher risk of the renal composite endpoint (HR 4.66, 95% CI 1.61-13.53, p = 0.005, p for trend = 0.001), regardless of EF. Empagliflozin reduced risk for cardiovascular death/HF hospitalization irrespective of baseline IGFBP7 (p for trend across IGFBP7 tertiles = 0.26). Empagliflozin treatment was not associated with meaningful change in IGFBP7 at 12 or 52 weeks.

CONCLUSION

Across the entire left ventricular EF spectrum in the EMPEROR Programme, concentrations of the senescence-associated biomarker IGFBP7 were associated with higher risk clinical status and predicted adverse cardio-renal outcomes even in models adjusted for conventional biomarkers. Empagliflozin did not significantly affect IGFBP7 levels over time.

Low-affinity insulin-like growth factor binding protein 7 and its association with pulmonary arterial hypertension severity and survival

Insulin-like growth factor (IGF) binding proteins (IGFBPs) are a family of growth factor modifiers, some of which are known to be independently associated with pulmonary arterial hypertension (PAH) survival. IGF factor binding protein 7 (IGFBP7) is a unique low-affinity IGFBP that, independent of IGF, stimulates prostacyclin production. This study proposed to establish associations between IGFBP7 and PAH severity and survival, using enrollment and longitudinal samples. Serum IGFBP7 levels were significantly elevated in patients with PAH compared to controls. After adjusting for age and sex, logarithmic increases in IGFBP7 were associated with a 20 m shorter six-minute walk distance (6MWD; p < 0.001), a 2-3 mmHg higher mean right atrial pressure (p < 0.001 and 0.02), and a higher likelihood of a greater REVEAL 2.0 risk category placement (p < 0.001). Kaplan-Meier analysis demonstrated significantly decreased survival with IGFBP7 above the median and Cox multivariable analysis adjusted for age and sex, demonstrated higher serum IGFBP7 was an independent predictor of survival. Though the exact mechanism is still unknown, given IGFBP7's role as a prostacyclin stimulant, it has potential use as a therapeutic target for disease modulation.

IGFBP-7 and Outcomes in Heart Failure With Reduced Ejection Fraction: Findings From DAPA-HF

BACKGROUND

Insulin-like growth factor-binding protein-7 (IGFBP-7) has been proposed as a potential prognostic biomarker in heart failure (HF), but the association between elevation in IGFBP-7 and HF outcomes in ambulant patients with heart failure with reduced ejection fraction (HFrEF) is unknown.

OBJECTIVES

The authors addressed this question in a post hoc analysis of the DAPA-HF (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure) trial.

METHODS

The primary outcome was a composite of cardiovascular death or a worsening HF event. The risk of adverse outcome was compared across tertiles of IGFBP-7 concentration by means of Cox proportional hazard models adjusted for N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hsTnT). The efficacy of randomized treatment across IGFBP-7 tertiles was assessed. Change in IGFBP-7 at 12 months was compared with the use of geometric means.

RESULTS

A total of 3,158 patients had IGFBP-7 measured at baseline, and 2,493 had a repeated measure at 12 months. Patients in the highest tertile of IGFBP-7 had evidence of more advanced HFrEF. The adjusted HR for the primary endpoint in tertile 3, compared with tertile 1, was 1.48 (95% CI: 1.17-1.88). There was no modification of the benefit of dapagliflozin by baseline IGFBP-7 (P interaction = 0.34). Dapagliflozin did not change IGFBP-7 levels over 1 year (P = 0.34).

CONCLUSIONS

Higher IGFBP-7 in patients with HFrEF was associated with worse clinical profile and an increased risk of adverse clinical outcomes. IGFBP-7 provided prognostic information incremental to clinical variables, NT-proBNP, and hsTnT. The benefit of dapagliflozin was not modulated by IGFBP-7 level. (Study to Evaluate the Effect of Dapagliflozin on the Incidence of Worsening Heart Failure or Cardiovascular Death in Patients With Chronic Heart Failure [DAPA-HF]; NCT03036124).

Data on plasma tumour and metabolism related proteins' potential in differentiation of HFpEF-PH from PAH and in prognosis of left heart failure patients with pulmonary hypertension

The data in the current paper constitutes supplementary material to our article entitled “Plasma tumour and metabolism related biomarkers AMBP, LPL and Glyoxalase I differentiate heart failure with preserved ejection fraction with pulmonary hypertension from pulmonary arterial hypertension” Ahmed et al. (2021). The study investigated 69 plasma tumour- and metabolism related proteins in healthy controls (n = 20) and in 115 patients of whom 48 had pulmonary arterial hypertension (PAH; n = 48) and 67 with left heart failure with pulmonary hypertension (LHF-PH) [heart failure with- preserved ejection fraction-PH (HFpEF-PH; n = 31) and reduced ejection fraction-PH (HFrEF-PH; n = 36)]. The haemodynamic data were obtained with right heart catheterization, and clinical data from medical records. The present article describe the plasma levels of tumour- and metabolism related proteins, analyzed with proximity extension assay, along with their uni- and multivariable diagnostic and prognostic potential. High sRAGE levels univariably emerged as a negative prognostic marker in LHF-PH.

Plasma tumour and metabolism related biomarkers AMBP, LPL and Glyoxalase I differentiate heart failure with preserved ejection fraction with pulmonary hypertension from pulmonary arterial hypertension

BACKGROUND

Discrimination of heart failure with preserved ejection fraction with pulmonary hypertension (HFpEF-PH) from pulmonary arterial hypertension (PAH) is crucial for clinical management but may be challenging due to similarities in clinical and comorbid characteristics. We aimed to investigate tumour and metabolism related proteins in differentiating HFpEF-PH from PAH.

METHODS

Sixty-nine tumour and metabolism plasma proteins were analysed with proximity extension assay in heathy controls (n = 20), patients with PAH (n = 48) and LHF-PH (n = 67) [HFpEF-PH (n = 31) and HF reduced EF-PH (n = 36)]. Haemodynamics were assessed with right heart catheterization.

RESULTS

The plasma levels of alpha-1-microglobulin/bikunin precursor (AMBP) and lipoprotein lipase (LPL), were higher in HFpEF-PH compared to healthy controls (p < 0.01), HFrEF-PH (p < 0.05), and PAH (p < 0.001). Glyoxalase I levels were higher in HFpEF-PH and HFrEF-PH compared to controls (p < 0.001) and PAH (p < 0.001). Each of plasma AMBP, LPL, and glyoxalase I, adjusted for age and sex in multivariable logistic regression models, could differentiate HFpEF-PH from PAH, with areas under the receiver operating characteristic curve (AUC) of 0.81, 0.84 and 0.79, respectively. The combination of AMBP, LPL and glyoxalse I yielded the largest AUC of 0.87 [95% confidence interval (0.79-0.95)] in discriminating HFpEF-PH from PAH, with a sensitivity of 87.1% and a specificity of 85.4%. In HFpEF-PH, the plasma levels of AMBP correlated with pulmonary arterial wedge pressure (r_s = -0.42, p = 0.018).

CONCLUSIONS

Plasma AMBP, LPL and glyoxalase I may facilitate the distinction of HFpEF-PH from PAH. Larger clinical studies are encouraged to confirm and validate our findings.

Genetic evidence for a causative effect of airflow obstruction on left ventricular filling: a Mendelian randomisation study

Background

Observational studies on the general population have suggested that airflow obstruction associates with left ventricular (LV) filling. To limit the influence of environmental risk factors/exposures, we used a Mendelian randomisation (MR) approach based on common genetic variations and tested whether a causative relation between airflow obstruction and LV filling can be detected.

Methods

We used summary statistics from large genome-wide association studies (GWAS) on the ratio of forced expiratory volume in 1 s to forced vital capacity (FEV1/FVC) measured by spirometry and the LV end-diastolic volume (LVEDV) as assessed by cardiac magnetic resonance imaging. The primary MR was based on an inverse variance weighted regression. Various complementary MR methods and subsets of the instrument variables were used to assess the plausibility of the findings.

Results

We obtained consistent evidence in our primary MR analysis and subsequent sensitivity analyses that reducing airflow obstruction leads to increased inflow to the LV (odds ratio [OR] from inverse variance weighted regression 1.05, 95% confidence interval [CI] 1.01–1.09, P = 0.0172). Sensitivity analyses indicated a certain extent of negative horizontal pleiotropy and the estimate from biased-corrected MR-Egger was adjusted upward (OR 1.2, 95% CI 1.09–1.31, P < 0.001). Prioritisation of single genetic variants revealed rs995758, rs2070600 and rs7733410 as major contributors to the MR result.

Conclusion

Our findings indicate a causal relationship between airflow obstruction and LV filling in the general population providing genetic context to observational associations. The results suggest that targeting (even subclinical) airflow obstruction can lead to direct cardiac improvements, demonstrated by an increase in LVEDV. Functional annotation of single genetic variants contributing most to the causal effect estimate could help to prioritise biological underpinnings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01795-9.

Elevated plasma sRAGE and IGFBP7 in heart failure decrease after heart transplantation in association with haemodynamics

Aims

Metabolic derangement is implicated in the pathophysiology of heart failure (HF) and pulmonary hypertension (PH). We aimed to identify the dynamics of metabolic plasma proteins linked to end‐stage HF and associated PH in relation to haemodynamics, before and after heart transplantation (HT).

Methods and results

Twenty‐one metabolic plasma proteins were analysed with proximity extension assay in 20 controls and 26 patients before and 1 year after HT. Right heart catheterizations were performed in the HF patients pre‐operatively and 1 year after HT. Plasma levels of soluble receptor for advanced glycation end products (sRAGE) and insulin‐like growth factor‐binding protein 7 (IGFBP7) were higher in HF patients compared with controls (P < 0.0001) and decreased after HT (P < 0.0001), matching controls' levels. The decrease in sRAGE after HT correlated with improved mean pulmonary arterial pressure (r_s = 0.7; P < 0.0001), pulmonary arterial wedge pressure (r_s = 0.73; P < 0.0001), pulmonary vascular resistance (r_s = 0.65; P = 0.00062), and pulmonary arterial compliance (r_s = −0.52; P = 0.0074). The change in plasma IGFBP7 after HT correlated with improved mean right atrial pressure (r_s = 0.71; P = 0.00011) and N‐terminal pro‐brain natriuretic peptide (r_s = 0.71; P < 0.0001).

Conclusions

Our results indicate that plasma sRAGE may reflect passive pulmonary vascular congestion and the ‘mechanical’ state of the pulmonary vasculature in HF patients with or without related PH. Furthermore, sRAGE and IGFBP7 may provide additional insight into the pathophysiological mechanisms in HF and associated PH. Their potential clinical and therapeutic relevance in HF and associated PH need further investigation.