Microbiome abundance of Prevotellaceae in spondyloarthritis patients with positive depression screening: A cross-sectional analysis

Introduction

Patients with autoimmune/autoinflammatory diseases are at increased risk for major depressive disorder. In spondyloarthritis (SpA), the prevalence of mild depression is 40 % approximately. This study aimed to assess the differences in gut microbiome abundance profiles between control subjects and patients with SpA, as well as between patients with positive and negative depression screening.

Methods

Patients fulfilling the ASAS criteria for SpA and matched controls were included. Sociodemographic and clinical data were collected, including disease activity and functional impairment assessments. Stool samples were obtained for DNA extraction, 16S rRNA PCR amplification with MiSeq sequencing to determine microbiome profiles. All patients completed the PHQ-9, and a linear regression model was developed to assess associations, adjusting for age, sex, and disease factors.

Results

62 SpA patients and 30 controls were included. Patients presented more frequently gastrointestinal symptoms and elevated inflammatory markers. Patients with a positive PHQ-9 depression screening had higher disease activity (ASDAS-CRP median 3.05; IQR 2.70 to 3.50 vs. 2.30; IQR 1.35 to 2.90) and greater functional impairment (BASFI median 6.55; IQR 5.50 to 7.60 vs. 2.50; IQR 0.80 to 4.20). Microbiome analysis revealed differences according to depression screening. Regression analysis confirmed that greater functional impairment and higher Prevotellaceae abundance were associated with PHQ-9 scores (R² = 0.557).

Conclusion

Greater functional impairment is associated with higher depressive symptoms, while increased abundance of Prevotellaceae correlates with lower PHQ-9 scores in SpA patients. These findings suggest that gut microbiome may play a key role in depression risk with mechanistic and therapeutic implications.