Distinct Inflammation Biomarkers in Healthy Individuals and Patients with Schizophrenia: A Reliability Testing of Multiplex Cytokine Immunoassay by Bland-Altman Analysis.

ABSTRACT:

Objective

Since the inflammatory process has been implicated in the pathophysiology of psychiatric disorder, an important issue emerging is to assess the test-retest reliability of cytokine measurement in healthy individuals and patients with schizophrenia. The objective of the present study was to investigate the test-retest reliability of bead-based multiplex immunoassay technology (BMIT) for cytokine measurement by using a Bland-Altman plot (BAP).

Methods

Twenty healthy individuals and twenty patients with schizophrenia were enrolled, and a 17-plex cytokine assay was used to measure inflammatory biomarkers at baseline and two weeks later. The test-retest reliability was examined by BAP, 95% limits of agreement (LOA), intraclass correlation coefficient (ICC), and coefficient of repeatability (CoR).

Results

In the healthy controls, only interleukin (IL)-2, IL-13, IL-10, IL-17, and macrophage inflammatory protein-1? showed excellent ICC. The BAP with 95% LOA determined that 13 cytokines showed acceptable 95% LOA for a 2-week test-retest reliability, and only IL-1?, IL-12 and tumor necrosis factor (TNF)-? had significant test-retest bias. The CoR of cytokines varied significantly, ranging from 1.72 to 218.1. Compared with healthy controls, patients with schizophrenia showed significantly higher levels of IL-5, IL-13, and TNF-? and significantly lower levels of IL-4, IL-12, and interferon-gamma (IFN-?). Of these six cytokines, IL-12 and TNF-? were considered suboptimal reliability.

Conclusion

The findings from ICC and CoR implied that the test-retest reliability of BMIT for cytokine measurement were suboptimal. However, the BAP with 95% LOA confirmed that BMIT can reliably distinguish schizophrenia from healthy individuals in cytokine measurement, while significant within-subject variation and between-group overlapping were evident in cytokine expression.

SUBMITTER: Yeh TC 

PROVIDER: S-EPMC6710413 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature