# Association between advanced lung cancer inflammation index levels and ischemic stroke in patients with atrial fibrillation: a propensity score-matching analysis

## TL;DR

Higher levels of a lung cancer inflammation index are linked to lower risk of stroke in patients with atrial fibrillation.

## Contribution

This study reveals a protective association between Advanced Lung Cancer Inflammation Index and ischemic stroke in atrial fibrillation patients.

## Key findings

- A dose–response relationship was found between baseline ALI and stroke risk (p for non-linearity = 0.46).
- Higher ALI quintiles showed a graded protective effect against ischemic stroke.
- Results were consistent across subgroups and sensitivity analyses.

## Abstract

Inflammation is closely associated with atrial fibrillation (AF) complicated by stroke. The Advanced Lung Cancer Index (ALI) is a comprehensive indicator of inflammation; however, its relationship with AF-related stroke is unclear. Therefore, this retrospective study was conducted to explore the correlation between ALI and ischemic stroke in patients with AF.

Patients were divided into two groups according to the optimal cutoff value of ALI: low ALI and high ALI groups. The primary outcome was ischemic stroke in patients with AF. To ensure robustness of the findings, propensity score matching, multivariate logistic regression, inverse probability weighting models, and doubly robust analysis were performed.

Of 2,630 eligible patients (screened: 1,879), 15.6% had a past medical history of ischemic stroke. Restricted cubic splines showed a linear dose–response relationship between baseline ALI and stroke risk (p for non-linearity = 0.46). A propensity-adjusted doubly robust analysis of 874 matched patients revealed a graded protective effect with increasing ALI quintiles: compared with the Q1 group, the Q4 and Q5 groups had odds ratios of 0.38 (95% CI 0.25-0.58) and 0.54 (0.35-0.82), respectively. Consistency across subgroups and sensitivity analysis confirmed the robustness of the results.

ALI showed a significant protective association with ischemic stroke in participants with AF, as increased ALI level was associated with lower prevalence of ischemic stroke.