Evaluation of aqueous humor and serum clusterin levels in patients with glaucoma

BACKGROUND: To compare the aqueous humor (AH) and the serum clusterin levels of patients with pseudoexfoliation syndrome (PEX), pseudoexfoliation glaucoma (PEXG), and primary open-angle glaucoma (POAG) with each other and with an age- and sex-matched control group. METHODS: This prospective, cross-sectionalstudy evaluated 92 eyes from 92 adult cases of uncomplicated phacoemulsification and posterior chamber intraocular lens (IOL) implantation. The cases were divided into PEX, PEXG, POAG, and control groups. Serum samples were taken from the antecubital vein just before the surgery, and the AH samples were aspirated at the beginning of the surgery. Kruskal-Wallis H, One-way ANOVA, Mann-Whitney U with Bonferroni correction and Chi-Square tests were used for statistical analysis. RESULTS: The serum clusterin levels were the highest in the PEXG group, but no statistically significant differences were observed between the groups (p=0.633). The mean AH clusterin levels were 286.79±29.64 μg/mL in the PEXG group, 263.92±31.70 μg/mL in the PEX group, 272.59±49.71 μg/mL in the POAG group, and 193.50±62.38 μg/mL in the control group (p< 0.001). This came out to be 1.48 times increase for the PEXG group, 1.36 for the PEX group, and 1.41 for the POAG group when compared with the control subjects. CONCLUSIONS: A higher level of clusterin in the anterior chamber was found to be associated with PEX and PEXG. In addition, a high level of anterior chamber clusterin in POAG, which is a new finding, showed that this molecule might be important not only in pseudoexfoliation, but also other types of glaucoma like POAG.