# Hematological inflammatory indices and their relationship to the risk of hypertension

## TL;DR

This study finds that higher blood-based inflammation markers are linked to a greater risk of developing hypertension over time.

## Contribution

The study provides new evidence linking specific hematological inflammatory indices to long-term hypertension risk in a large population.

## Key findings

- Higher SII, SIRI, and NLR levels were significantly associated with increased hypertension risk in both genders.
- PLR showed a stronger positive association with hypertension risk in women compared to men.
- Elevated inflammatory indices were linked to hypertension risk even in young and healthy individuals.

## Abstract

Chronic inflammation has been implicated in the development of hypertension in numerous previous studies. However, evidence regarding the association between hematological inflammatory indices derived from complete blood count tests and the long-term risk of hypertension remains limited. Therefore, this study aimed to investigate the association between various hematological inflammatory indices and the risk of incident hypertension in a large cohort study.

We analyzed data from a large Korean cohort (n=128,241). The incident risk of hypertension was evaluated according to quartiles of the neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and systemic inflammatory response index (SIRI) using Cox proportional hazards models. Additional analyses were conducted for high-sensitivity C-reactive protein (hsCRP) levels and stratified by gender.

During a median follow-up of 6.8 years, 18,503 participants (14.4%) developed hypertension. Higher quartiles of SII, SIRI, and NLR were significantly associated with an increased risk of incident hypertension in both genders. PLR showed a clearer positive association in women, whereas MLR demonstrated only marginal associations. These patterns were consistent with the associations observed for hsCRP.

These findings suggest that elevated hematological inflammatory indices above certain thresholds are associated with an increased risk of hypertension, even among young and generally healthy individuals.