Tear Biomarkers of Idiopathic Intracranial Hypertension in Females
Research type
Research Study
Full title
Tear Fluid Cytokines and Metabolic Proteins as Novel, Non-Invasive Biomarkers of Idiopathic Intracranial Hypertension (IIH) in Female Subjects
IRAS ID
278641
Contact name
Suzanne Hagan
Contact email
Sponsor organisation
School of Health and Life Sciences, Glasgow Caledonian University
Duration of Study in the UK
0 years, 11 months, 31 days
Research summary
Summary of Research:
To date, no published data exists on tear fluid inflammatory proteins in patients with IIH. This pilot study provides an opportunity for a multidisciplinary investigation into the potential of tear fluid protein analysis to identify novel biomarkers as indicators of eye, neurological and immunological health in IIH. Data collected from this study will add to the knowledge base concerning IIH development.
This study therefore provides an opportunity to develop real-world tear fluid diagnostic tools, and/or therapeutic targets of IIH, using a biological fluid that is easily accessible and uses a non-invasive retrieval method.Summary of Results:
Idiopathic Intracranial Hypertension (IIH) is an under-researched, vision-threatening disorder which presents with raised pressure around the brain, headaches, double vision/vision loss and it mainly affects obese women of child-bearing age. To preserve vision in patients with IIH (pwIIH), rapid intervention (diagnosis and treatment) is necessary. Globally, IIH is increasing alongside obesity levels and IIH is now considered to be a metabolic condition, like diabetes.
The biology underpinning IIH is unclear, however, research shows changes to inflammatory and metabolic proteins in the blood and cerebrospinal fluid (CSF) of pwIIH which may be biological markers of IIH.
This pilot research investigated if there were differences in the protein levels of tear fluids from pwIIH. Both inflammation and metabolism-related proteins were measured in all subject tears to determine if tear proteins, along other clinical measures, may serve as new markers of IIH. The study included 17 healthy controls (non IIH) and 19 pwIIH whose tears were analysed for the presence of 3 metabolic proteins (leptin, insulin and ghrelin) and 7 inflammatory proteins (IL-6, IL-8, Il-1bIL-10, IL-1RA, MCP-1 and TNF-alpha). 9 of then 10 proteins were detectable in most subject tear samples. IL-1b was detected in less than 50% of subject tears and so was not further analysed. Significantly higher levels of the inflammatory proteins, IL-6 and IL-8 were observed in tear fluids from pwIIH versus healthy controls (p=0.002 and p=0.01, respectively). Furthermore, higher levels of the proteins leptin, insulin, ghrelin, TNF-alpha, IL-10, IL-1RA and MCP-1 were observed in pwIIH versus controls, but were not statistically significant.
This pilot study indicates that both inflammatory and metabolic proteins may be detected in the tear fluids of pwIIH and that 2 pro-inflammatory proteins, IL-6 and IL-8, were significantly raised when compared to healthy controls. This data indicates that IL-6 and IL-8 may serve as potential biomarkers of IIH. Future work will assess a larger cohort of subjects with and without IIH for a larger panel of proteins, to determine if other proteins are linked to IIH, as well to determine if tear fluid proteins are correlated with other clinical measures of IIH (body mass index/obesity, blood glucose levels, vision impairment).REC name
West of Scotland REC 5
REC reference
22/WS/0009
Date of REC Opinion
8 Feb 2022
REC opinion
Further Information Favourable Opinion