Serum uric acid is associated with disease severity and may predict clinical outcome in patients of pulmonary arterial hypertension secondary to connective tissue disease in Chinese: a single-center retrospective study

Association of serum uric acid with right cardiac chamber remodeling assessed by cardiovascular magnetic resonance feature tracking in patients with connective tissue disease

Background

Right cardiac chamber remodeling is widespread in patients with connective tissue disease (CTD). Serum uric acid (SUA) is considered a potential independent risk factor for cardiovascular disease, and elevated SUA levels are often observed in patients with CTD. The correlation between SUA levels and right cardiac chamber remodeling remains unclear. This study investigated the association of SUA with right cardiac chamber remodeling as assessed by cardiac magnetic resonance feature-tracking (CMR-FT) in CTD patients.

Methods and results

In this cross-sectional study, a total of 104 CTD patients and 52 age- and sex-matched controls were consecutively recruited. All individuals underwent CMR imaging, and their SUA levels were recorded. The patients were divided into three subgroups based on the tertiles of SUA level in the present study. CMR-FT was used to evaluate the right atrial (RA) longitudinal strain and strain rate parameters as well as right ventricular (RV) global systolic peak strain and strain rate in longitudinal and circumferential directions for each subject. Univariable and multivariable linear regression analyses were used to explore the association of SUA with RV and RA strain parameters. Compared with the controls, the CTD patients showed significantly higher SUA levels but a lower RV global circumferential strain (GCS) and RA phasic strain parameters (all p < 0.05), except the RA booster strain rate. RV GCS remained impaired even in CTD patients with preserved RV ejection fraction. Among subgroups, the patients in the third tertile had significantly impaired RV longitudinal strain (GLS), RV GCS, and RA reservoir and conduit strain compared with those in the first tertile (all p < 0.05). The SUA levels were negatively correlated with RV GLS and RV GCS as well as with RA reservoir and conduit strain and strain rates (the absolute values of β were 0.250 to 0.293, all P < 0.05). In the multivariable linear regression analysis, the SUA level was still an independent determinant of RA conduit strain (β = -0.212, P = 0.035) and RV GCS (β = 0.207, P = 0.019).

Conclusion

SUA may be a potential risk factor of right cardiac chamber remodeling and is independently associated with impaired RA conduit strain and RV GCS in CTD patients.

Association between uric acid and cardiac outcomes mediated by neutrophil-to-lymphocyte ratio in patients with left ventricular diastolic dysfunction and pulmonary hypertension

To evaluate the association of uric acid (UA) with adverse outcomes and its potential mediator in patients with left ventricular diastolic dysfunction (LVDD) and pulmonary hypertension (PH). We retrospectively analyzed 234 patients with LVDD and PH. The baseline characteristics of patients with low UA (≤ 330 µmol/L) group were compared with high UA (> 330 µmol/L) group. Adverse outcomes included all-cause mortality, cardiac death and heart failure (HF) hospitalization. Their association with UA and the mediator were evaluated using Cox regression and mediation analysis. The mediation proportion was further quantified by the R mediation package. During a mean follow-up of 50 ± 18 months, there were 27 all-cause deaths, 18 cardiovascular deaths and 41 incidents of HF hospitalization. Multivariable Cox regression analysis showed UA was an independent risk factor of adverse outcomes in LVDD and PH patients, even after adjusting for age, sex, body mass index, medical histories, systolic blood pressure, fasting blood glucose, total cholesterol, triglyceride, eGFR, BNP and medications. The hazard ratios (HRs) for UA (per 10 µmol/L increase) were as below: for all-cause mortality, HR 1.143, 95% CI 1.069-1.221, P < 0.001; for cardiac death, HR 1.168, 95% CI 1.064-1.282, P = 0.001; for HF hospitalization, HR 1.093, 95% CI 1.035-1.155, P = 0.001. Neutrophil-to-lymphocyte ratio (NLR) played a partial mediation role in the association, and the mediation proportion for NLR on the UA-adverse outcomes were 21%, 19% and 17%, respectively. In patients of LVDD with PH, higher UA level was independently correlated with adverse outcomes. Furthermore, NLR partially mediated the effect of UA on the risk of all-cause mortality, cardiac death and HF hospitalization.

Clinical characteristics and prognosis in systemic lupus erythematosus-associated pulmonary arterial hypertension based on consensus clustering and risk prediction model

BACKGROUND

Pulmonary arterial hypertension (PAH) is a severe complication of systemic lupus erythematosus (SLE). This study aims to explore the clinical characteristics and prognosis in SLE-PAH based on consensus clustering and risk prediction model.

METHODS

A total of 205 PAH (including 163 SLE-PAH and 42 idiopathic PAH) patients were enrolled retrospectively based on medical records at the First Affiliated Hospital of Zhengzhou University from July 2014 to June 2021. Unsupervised consensus clustering was used to identify SLE-PAH subtypes that best represent the data pattern. The Kaplan-Meier survival was analyzed in different subtypes. Besides, the least absolute shrinkage and selection operator combined with Cox proportional hazards regression model were performed to construct the SLE-PAH risk prediction model.

RESULTS

Clustering analysis defined two subtypes, cluster 1 (n = 134) and cluster 2 (n = 29). Compared with cluster 1, SLE-PAH patients in cluster 2 had less favorable levels of poor cardiac, kidney, and coagulation function markers, with higher SLE disease activity, less frequency of PAH medications, and lower survival rate within 2 years (86.2% vs. 92.8%) (P < 0.05). The risk prediction model was also constructed, including older age at diagnosis (≥ 38 years), anti-dsDNA antibody, neuropsychiatric lupus, and platelet distribution width (PDW).

CONCLUSIONS

Consensus clustering identified two distinct SLE-PAH subtypes which were associated with survival outcomes. Four prognostic factors for death were discovered to construct the SLE-PAH risk prediction model.

Biomarkers in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a severe medical condition characterized by elevated pulmonary vascular resistance (PVR), right ventricular (RV) failure, and death in the absence of appropriate treatment. The progression and prognosis are strictly related to the etiology, biochemical parameters, and treatment response. The gold-standard test remains right-sided heart catheterization, but dynamic monitoring of systolic pressure in the pulmonary artery is performed using echocardiography. However, simple and easily accessible non-invasive assays are also required in order to monitor this pathology. In addition, research in this area is in continuous development. In recent years, more and more biomarkers have been studied and included in clinical guidelines. These biomarkers can be categorized based on their associations with inflammation, endothelial cell dysfunction, cardiac fibrosis, oxidative stress, and metabolic disorders. Moreover, biomarkers can be easily detected in blood and urine and correlated with disease severity, playing an important role in diagnosis, prognosis, and disease progression.

The obstetric implications of pulmonary hypertension and lung transplant

Pulmonary hypertension (PH) is present when the mean pulmonary artery pressure is elevated to >20 mmHg as determined by right heart catheterization. It is categorized into five groups according to the underlying causes. Its presence is considered a contraindication to pregnancy for which therapeutic termination is usually advised due to grave maternal prognosis and pregnancy outcome. Nevertheless, pregnancies in affected women are increasingly reported, about half of which were unplanned, and two-thirds resulted in live births without increased foetal anomalies, notwithstanding increased risks of preterm birth, low birth weight, pre-eclampsia, other obstetric complications, and medical comorbidities, when managed under a multidisciplinary team in specialized centres. Successful lung transplant, the ultimate treatment for PH and other progressive lung diseases, restores fertility, and pregnancy is increasingly encountered, but there is a higher risk of graft rejection and mortality, compared with recipients of other organs. Preconception assessment is vital in optimizing maternal and pregnancy outcomes.

The Prognostic Impact of Serum Uric Acid on Disease Severity and 5-Year Mortality in Patients With Idiopathic Pulmonary Artery Hypertension

Background

Serum uric acid (UA) has long been identified as a prognostic factor of adverse outcomes in pulmonary hypertension. However, there remains a paucity of evidence on patients with idiopathic pulmonary artery hypertension (IPAH) in the era of targeted drug therapy. This study aims to explore the impact of serum UA levels on the disease severity and mortality in patients with IPAH.

Methods

Consecutive patients diagnosed with IPAH were enrolled, from which UA levels at baseline and the first follow-up were collected. Patients were divided into groups of “hyperuricemia,” which is defined as serum UA level ≥357 μmol/L in women and ≥420 μmol/L in men, and otherwise “normouricemia.” The potential relationship between UA and hemodynamics at right heart catheterization was investigated. Associations between UA and survival were evaluated by Kaplan-Meier analysis and Cox proportional hazard modeling.

Results

Of 207 patients with IPAH, 121 (58.5%) had hyperuricemia. Higher serum UA levels were associated with lower cardiac index (r = 0.47, p < 0.001) and higher pulmonary vascular resistance (r = 0.36, p < 0.001). During a median follow-up of 34 months, there were 32 deaths recorded, accounting for a 15.5% mortality rate. Patients with hyperuricemia had a significantly lower survival rate than those with normouricemia (log-rank test, p = 0.002). Hyperuricemia at baseline was independently associated with a 2.6-fold increased risk of 5-year death, which was consistent across different subgroups, especially in females and those aged ≥30 years (each p < 0.05). Individuals with higher variability in UA had a higher mortality than those with stable UA (log-rank test, p = 0.024).

Conclusions

Baseline hyperuricemia and high variability in serum UA at first follow-up were related to a higher rate of 5-year mortality in patients with IPAH. Closely detecting the UA levels may aid in the early recognition of IPAH patients at higher mortality risk.

Circulating Blood-Based Biomarkers in Pulmonary Hypertension

Pulmonary hypertension (PH) is a serious hemodynamic condition, characterized by increased pulmonary vascular resistance (PVR), leading to right heart failure (HF) and death when not properly treated. The prognosis of PH depends on etiology, hemodynamic and biochemical parameters, as well as on response to specific treatment. Biomarkers appear to be useful noninvasive tools, providing information about the disease severity, treatment response, and prognosis. However, given the complexity of PH, it is impossible for a single biomarker to be adequate for the broad assessment of patients with different types of PH. The search for novel emerging biomarkers is still ongoing, resulting in a few potential biomarkers mirroring numerous pathophysiological courses. In this review, markers related to HF, myocardial remodeling, inflammation, hypoxia and tissue damage, and endothelial and pulmonary smooth muscle cell dysfunction are discussed in terms of diagnosis and prognosis. Extracellular vesicles and other markers with complex backgrounds are also reviewed. In conclusion, although many promising biomarkers have been identified and studied in recent years, there are still insufficient data on the application of multimarker strategies for monitoring and risk stratification in PH patients.

Association Between Uric Acid and Worsening Peripheral Microangiopathy in Systemic Sclerosis

Objective: The key element in the pathogenesis of systemic sclerosis (SSc) is microcirculatory changes in several vascular beds. Uric acid is associated with endothelial dysfunction and therefore, microvascular damage. The aim of this study was to examine the association between uric acid (UA) and peripheral microvascular involvement in patients with SSc. Methods: We included consecutive, consenting patients with SSc. Serum UA, urea and creatinine were measured, and glomerular filtration rate (GFR) was calculated with CKD-EPI. All participants underwent nailfold video-capillaroscopy (NVC) to evaluate the microcirculation. Results: A total of 64 patients (95.3% women) were included in the study. UA levels were significantly associated with the number of avascular areas (r = 0.290; p = 0.020), whereas no correlation was shown for the GFR (r = -0.065; p = 0.609). A significant trend of UA in the three capillaroscopic patterns was shown (3.90 ± 1.52 vs. 4.15 ± 0.98 vs. 5.38 ± 2.26; for early, active, and late patterns respectively, p = 0.028). Multivariate analysis showed that male gender (β = 3.049; 95% CI = 0.997-5.101) and UA (β = 0.352; 95% CI = 0.117-0.588) were independently associated with the number of avascular areas. Conclusion: These data suggest that UA levels are significantly associated with the capillaroscopic patterns, reflecting a progressive microvasculopathy.