45 patients affected by
glaucoma at different stages and 15 age-matched healthy control subjects underwent visual field testing, peripapillary
retinal nerve fibre layer thickness measurement using Spectral Domain Optical Coherence Tomography and blood collection for both
neurotrophins detection by
Enzyme-Linked
Immunosorbent Assay. Statistical analysis and association between biostrumental and biochemical data were investigated.
RESULTS: Serum levels of
BDNF in
glaucoma patients were significantly lower than those measured in healthy controls (261.2±75.0 pg/ml vs 313.6±79.6 pg/ml, p = 0.03). Subgroups analysis showed that serum levels of
BDNF were significantly lower in early (253.8±40.7 pg/ml, p = 0.019) and moderate
glaucoma (231.3±54.3 pg/ml, p = 0.04) but not in advanced
glaucoma (296.2±103.1 pg/ml, p = 0.06) compared to healthy controls. Serum levels of
NGF in
glaucoma patients were significantly lower than those measured in the healthy controls (4.1±1 pg/mL vs 5.5±1.2 pg/mL, p = 0.01). Subgroups analysis showed that serum levels of
NGF were significantly lower in early (3.5±0.9 pg/mL, p = 0.0008) and moderate
glaucoma (3.8±0.7 pg/ml, p<0.0001) but not in advanced
glaucoma (5.0±0.7 pg/ml, p = 0.32) compared to healthy controls.
BDNF serum levels were not related to age, visual field mean deviation or
retinal nerve fibre layer thickness either in
glaucoma or in controls while
NGF levels were significantly related to visual field mean deviation in the
glaucoma group (r2 = 0.26, p = 0.004).
CONCLUSIONS:
BDNF and
NGF serum levels are reduced in the early and moderate
glaucoma stages, suggesting the possibility that both factors could be further investigated as potential circulating
biomarkers for the early detection of
glaucoma.