Plasma proenkephalin A and incident chronic kidney disease and albuminuria in the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort

BACKGROUND

Plasma proenkephalin A (PENK-A) is a precursor of active enkephalins. Higher blood concentrations have been associated with estimated glomerular filtration rate (eGFR) decline in European populations. Due to the significant disparity in incident chronic kidney disease (CKD) between White and Black people, we evaluated the association of PENK-A with incident CKD and other kidney outcomes among a biracial cohort in the U.S.

METHODS

In a nested cohort of 4,400 participants among the REasons for Geographic And Racial Differences in Stroke, we determined the association between baseline PENK-A concentration and incident CKD using the creatinine-cystatin C CKD-EPI 2021 equation without race coefficient, significant eGFR decline, and incident albuminuria between baseline and a follow-up visit 9.4 years later. We tested for race and sex interactions. We used inverse probability sampling weights to account for the sampling design.

RESULTS

At baseline, mean (SD) age was 64 (8) years, 49% were women, and 52% were Black participants. 8.5% developed CKD, 21% experienced ≥ 30% decline in eGFR and 18% developed albuminuria. There was no association between PENK-A and incident CKD and no difference by race or sex. However, higher PENK-A was associated with increased odds of progressive eGFR decline (OR: 1.12; 95% CI 1.00, 1.25). Higher PENK-A concentration was strongly associated with incident albuminuria among patients without diabetes mellitus (OR: 1.29; 95% CI 1.09, 1.53).

CONCLUSION

While PENK-A was not associated with incident CKD, its associations with progression of CKD and incident albuminuria, among patients without diabetes, suggest that it might be a useful tool in the evaluation of kidney disease among White and Black patients.

Proenkephalin A and bioactive adrenomedullin are useful for risk prognostication in cardiac surgery

Introduction

Various clinical scores have been developed to predict organ dysfunction and mortality in patients undergoing cardiac surgery, but outcome prediction may be inaccurate for some patient groups. Proenkephalin A (penKid) and bioactive adrenomedullin (bio-ADM) have emerged as promising biomarkers correlating with shock and organ dysfunction. This imposes the question of whether they can be used as prognostic biomarkers for risk stratification in the perioperative setting of cardiac surgery.

Methods

Patients undergoing cardiac surgery were prospectively enrolled in this observational study. PenKid and bio-ADM plasma levels, as well as markers evaluating inflammation and organ dysfunction, were measured at five perioperative time points from before the induction of anesthesia to up to 48 h postoperatively. Clinical data regarding organ dysfunction and patient outcomes were recorded during the intensive care unit (ICU)-stay with a special focus on acute kidney injury (AKI).

Results

In 136 patients undergoing cardiac surgery, the bio-ADM levels increased and the penKid levels decreased significantly over time. PenKid was associated with chronic kidney disease (CKD), the incidence of AKI, and renal replacement therapy (RRT). Bio-ADM was associated with lactate and the need for vasopressors. PenKid was useful to predict an ICU-length of stay (LOS)>1 day and added prognostic value to the European System for Cardiac Operative Risk Evaluation Score (EuroSCORE) II when measured after the end of cardiopulmonary bypass and 24 h after cardiac surgery. For bio-ADM, the same was true when measured 24 h after surgery. PenKid also added prognostic value to the EuroSCORE II for the combined outcome "ICU length of stay >1 day and in-hospital mortality."

Conclusion

The combination of preoperative EuroSCORE II and intraoperative measurement of penKid may be more useful to predict a prolonged ICU LOS and increased mortality than EuroSCORE II alone. Bio-ADM correlates with markers of shock. More research is encouraged for early risk stratification and validation of penKid and bio-ADM as a tool involved in clinical decisions, which may enable the early initiation of organ protective strategies.

Proenkephalin A Adds No Incremental Prognostic Value After Acute Ischemic Stroke

Objective:

The aim of this study was to confirm previous observations that proenkephalin A (PENK-A) may serve as prognostic marker in the setting of acute ischemic stroke in a large stroke cohort.

Methods:

The plasma concentration of PENK-A was measured within 72 hours of symptom onset in 320 consecutively enrolled patients with stroke. The primary outcome measures were unfavorable functional outcome (modified Rankin Scale score 0-2 vs 3-6) and mortality within 90 days. Logistic and cox proportional regression analyses were fitted to estimate odds ratios (ORs), hazard ratios (HRs) and 95% confidence intervals (CIs), respectively, for the association between PENK-A and the primary outcome measures.

Results:

After adjusting for demographic and vascular risk factors, PENK-A was neither independently associated with functional outcome (OR: 1.29, 95% CI: 0.16-10.35) nor mortality (HR: 1.02, 95% CI: 0.14-7.33).

Conclusion:

Among patients with acute stroke, PENK-A does not serve as an independent prognostic marker in this external validation cohort.