Early Detection of Inflammation and Malnutrition and Prediction of Acute Events in Hemodialysis Patients through PINI (Prognostic Inflammatory and Nutritional Index)

Abstract

Protein-energy wasting and inflammation are major risk factors for complications in hemodialysis patients. As these risk factors are triggered by a pro-inflammatory state, oxidative stress and hemodynamic dysfunction, which overlap in hemodialyzed subjects, we aimed to assess the efficacy of a cost-effective and straightforward screening tool, the Prognostic Inflammatory and Nutritional Index (PINI), in regularly screening maintenance hemodialysis (MHD) patients, to detect early signs of inflammation and malnutrition. A 12-month follow-up was carried out on a cohort of 102 adult patients undergoing maintenance dialysis, during which the Prognostic Inflammatory and Nutritional Index (PINI) was calculated using the formula alpha1-Acid Glycoprotein (AGP) × C-reactive protein (CRP)/albumin (ALB) × transthyretin (TTR). A PINI score < 1 was considered normal. The patients were stratified based on their PINI score: 66 patients (64.70%) had a normal score, below 1, while 36 patients (35.30%) had a PINI score ≥ 1. Despite the absence of clinical evidence of inflammation at enrollment, the latter group exhibited higher levels of CRP. During the follow-up period, all patients with a PINI score ≥ 1 experienced at least one acute event, compared to only 6% of patients with a normal PINI score, which presented COVID-19 infection as an acute event. The evaluation of the PINI can effectively identify the silent malnutrition-inflammation syndrome and predict the risk of acute events. This straightforward test appears to be a rapid tool that is independent of the examiner's experience and subjectivity, thereby potentially reducing hospitalization costs.

Keywords: PINI; acute events; hemodialysis; inflammation; malnutrition; protein-energy wasting.

Figure 1

Distribution of pathologies associated with the group with PINI ≥ 1. DN—diabetic nephropathy; GN—glomerular nephropathy; ADPKD—autosomal dominant polycystic disease; IN—ischemic nephropathy; TIN—tubulo-interstitial nephropathy.

Figure 2

The distribution of patients by PINI value and the presence of acute events.

Figure 3

Vascular approach in hemodialysis patients with PINI ≥ 1. CVC—central venous catheter; AVF—arteriovenous fistula.

Figure 4

Correlation between albumin and transthyretin.

Figure 5

(a) Kaplan–Meier analysis for evaluating the survival rate compared by PINI value; (b) Kaplan–Meier curve for evaluating the rate of acute events compared by PINI value.

Figure 5

(a) Kaplan–Meier analysis for evaluating the survival rate compared by PINI value; (b) Kaplan–Meier curve for evaluating the rate of acute events compared by PINI value.