Phenylacetylglutamine, anaemia and outcomes in ischaemic heart failure: a cohort study

Objectives This study aimed to measure the level of phenylacetylglutamine (PAGln) and its correlation with anaemia in ischaemic heart failure (HF) patients. Design A prospective cohort study. Setting The study was conducted at Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. Participants A total of 89 ischaemic heart failure (IHD) patients confirmed by symptoms, echocardiography and coronary angiography and 75 healthy controls were enrolled (all aged≥18 years). Primary and secondary outcome measures The primary outcome was the association between serum PAGln levels and low haemoglobin (HGB). The secondary outcome was to explore the composite endpoint of cardiovascular death and HF hospitalisations during 1 year of follow-up. Results The PAGln levels were significantly higher in IHD patients compared with the control population (716 (440–1097) vs 411 (202–697) ng/mL, p<0.001). There were 27 IHD patients who had low HGB (27/89). In HF patients with IHD, after adjustment for age and log N-terminal brain natriuretic peptide (NT-proBNP), the tertiles of PAGln were associated with low HGB (OR, 2.610; 95% CI: 1.251 to 5.447; p=0.011). Moreover, during the 1 year follow-up, PAGln levels continued to demonstrate the relationship with HF endpoints (19/73, 26.0%) (HR=3.547, 95% CI: 1.254 to 10.034, p=0.017), even after adjusting for HGB and log NT-proBNP in Cox regression analysis. Conclusions In HF patients with IHD, the elevated PAGln levels were related to reduced HGB. Additionally, the increased PAGln concentrations with low HGB were linked to poor HF endpoint events.