Serum Brain-Derived Neurotrophic Factor: An Emerging Marker for Diabetic Retinopathy.

BACKGROUND

Diabetes mellitus (DM) is a global disease that is strongly associated with both microvascular and macrovascular complications. A significant proportion of individuals with diabetes develop diabetic retinopathy (DR), a microvascular complication that can lead to blindness, particularly in working-age adults. Diabetes adversely affects the entire neurosensory retina, with accelerated neuronal apoptosis and activation or altered metabolism of neuroretinal supporting cells. These findings suggest that DR could be a sensory neuropathy that affects the retinal parenchyma, similar to peripheral diabetic neuropathy. Neurotrophins have been implicated in the progression of DR. This study was done to determine the association of serum brain-derived neurotrophic factor (BDNF) levels with DR in type 2 diabetic patients in a tertiary care hospital in North India.

METHODS

A hospital-based case-control study was done. The case group included diabetic patients with retinopathy (n=44) and the control group included diabetic patients without retinopathy (n=44). Serum BDNF levels were estimated by enzyme-linked immunosorbent assay (ELISA). Statistical analysis was carried out using GraphPad Prism software (Dotmatics, Boston, USA).

RESULTS

The mean serum BDNF in the control and case groups was 2753 ± 465 pg/ml and 1598 ± 483 pg/ml, respectively. The difference between the two groups was statistically significant as per the Mann-Whitney U test (U=64, p<0.0001). Logistic regression analysis showed that BDNF is a good predictor for DR after multivariate regression.

CONCLUSIONS

Patients with DR were found to have lower serum BDNF levels compared to those without retinopathy. BDNF may serve as an early predictor for DR. Due to its role in neuronal health and metabolism, increasing BDNF levels could offer a therapeutic approach to managing diabetes-related complications. However, further research is needed to confirm the effectiveness of BDNF in slowing or preventing the progression of DR.