# Correlations between personality traits, personality disorders, and immunometabolic markers

## TL;DR

This study found a link between the personality trait neuroticism and elevated levels of leptin, an immunometabolic marker, in individuals with psychiatric disorders.

## Contribution

The study provides new evidence of a correlation between neuroticism and leptin levels, suggesting a biological link between personality traits and immunometabolic markers.

## Key findings

- Neuroticism was positively correlated with leptin levels (ρ = 0.31, p = 0.02).
- Brain-derived neurotrophic factor was also positively correlated with neuroticism (ρ = 0.36, p < 0.01).
- No significant relationships were found between personality disorders and immunometabolic markers.

## Abstract

Evidence links immune system alterations to major psychiatric disorders. The few previous studies on personality traits or personality disorders (PDs) indicate that immunometabolic dysregulation may be prevalent in this population. This study aimed to investigate relationships between personality traits, PDs, and immunometabolic markers in peripheral blood. We hypothesized that neuroticism would be correlated with elevated leptin. Participants were recruited as young adults seeking care for general psychiatric disorders. They responded to a personality inventory and were assessed for PDs, and reevaluated again at a 12 years follow-up. Blood samples were collected at the follow-up and analyzed for 29 immunometabolic markers. A positive correlation was found between the personality trait neuroticism and leptin (ρ = 0.31, p = 0.02). An exploratory analysis also revealed a positive correlation between brain-derived neurotrophic factor (ρ = 0.36, p < 0.01) and neuroticism. These findings remained after adjusting for other variables in general linear models. There were no relationships between PDs and any immunometabolic markers. Results both confirm previous findings of correlations between the immunometabolic system and personality traits and suggest directions for future research.