# Investigating the association of pan-immune-inflammation value, systemic immune-inflammation index, and neutrophil-to-lymphocyte ratio with pain in Parkinson’s disease

## TL;DR

This study investigates how inflammation markers relate to pain in Parkinson’s disease patients, finding that certain markers are linked to higher pain and disease severity.

## Contribution

The study introduces novel composite inflammatory markers (PIV, SII, NLR) as potential indicators of pain in Parkinson’s disease.

## Key findings

- PD patients with pain had significantly higher PIV and SII/100 levels compared to those without pain.
- KPPS scores correlated with PIV, disease stage, motor impairment, and depression but not with SII/100 or NLR.
- Inflammatory dysregulation is evident in PD patients, with pain linked to greater disease severity and depressive symptoms.

## Abstract

To explore the relationship between novel composite inflammatory markers—pan-immune-inflammation value (PIV), systemic immune-inflammation index (SII), and neutrophil-to-lymphocyte ratio (NLR)—and the presence of pain in patients with Parkinson’s disease (PD).

A total of 150 PD patients who attended the outpatient or inpatient departments of the Second Clinical College of Xuzhou Medical University (Huai’an Third People’s Hospital) between September 2020 and December 2023 were enrolled as the PD group. An additional 150 age- and sex-matched healthy individuals undergoing routine physical examinations were selected as the healthy control (HC) group. The King’s Parkinson’s Disease Pain Scale (KPPS), Hoehn-Yahr (H-Y) staging, Unified Parkinson’s Disease Rating Scale part III (UPDRS-III), Hamilton Depression Rating Scale-24 (HAMD-24), and Hamilton Anxiety Rating Scale (HAMA) were used to assess pain, disease severity, motor symptoms, depression, and anxiety in PD patients. Demographic and laboratory data were collected for all participants. Based on KPPS scores, PD patients were subdivided into those with pain (PDP group) and those without pain (nPDP group). Intergroup differences were compared, and the associations of PIV, SII, and NLR with pain in PD were analyzed.

Among the 150 PD patients, 79 (52.7%) reported pain, with a mean KPPS score of 10.81 ± 8.67. Compared to the HC group, PD patients exhibited significantly elevated levels of PIV, SII/100, and NLR, and significantly lower platelet and lymphocyte counts (p < 0.05). In subgroup analysis, PIV, SII/100, H-Y stage, UPDRS-III, and HAMD-24 scores were significantly higher in the PDP group than in the nPDP group (p < 0.05). KPPS scores were positively correlated with PIV, H-Y stage, UPDRS-III, and HAMD-24 scores, but not with SII/100 or NLR.

Inflammatory dysregulation is present in PD patients. Compared with the nPDP group, patients in the PDP group showed significantly higher levels of PIV and SII/100, as well as greater disease severity (H-Y stage, UPDRS-III) and more pronounced depressive symptoms (HAMD-24) (p < 0.05). Moreover, KPPS scores in PD patients were not only associated with PIV but also positively correlated with disease stage, motor function impairment, overall disease severity, anxiety, and depression.