BACKGROUND: Alzheimer’s disease (AD) is a degenerative disease that is characterized by massive neuron devastations in the hippocampus and cortex. Mild cognitive impairment (MCI) is the transitory stage between normality and AD dementia. This study aimed to investigate the melatonin induced effects on the lamina cribrosa thickness (LCT) of patients with MCI.

MATERIAL AND METHODS: The LCT data of patients with MCI were compared to LCT data of healthy controls. Subsequently, all MCI patients were randomly assigned into an experimental group (with melatonin treatment) or a placebo group (without any melatonin treatment).

RESULTS: The LCT of MCI patients decreased significantly compared with healthy controls. The univariate analysis showed that the lower the Mini Mental State Examination (MMSE) score (P=0.038; 95% CI: 0.876, –0.209), the smaller hippocampus volume (P=0.001; 95% CI: –1.594, –2.911), and the upregulated level of cerebrospinal fluid (CSF) T-tau (P=0.036; 95% CI: 2.546, –0.271) were associated significantly with the thinner LCT in MCI patients. There were 40 patients in the experimental group and 39 patients in the placebo group. The mean age of the experimental group was not significantly different from the placebo group (66.3±8.8 versus 66.5±8.3; P>0.05). The LCT and hippocampus volume of the melatonin treated group were significantly larger compared with the placebo group (P<0.001). On the other hand, the CSF T-tau level of the melatonin treated group was significantly lower compared with the untreated group (P<0.001).

CONCLUSIONS: LCT assessment might allow early diagnosis of MCI. Dietary melatonin therapy could provide an effective medication for MCI patients with LCT alterations.

Keywords: Diagnostic Techniques, Ophthalmological, Eye Abnormalities, Retinaldehyde, Aged, 80 and over, Alzheimer Disease, Amyloid beta-Peptides, cognitive dysfunction, Cornea, Descemet Membrane, Dietary Supplements, Disease Progression, Double-Blind Method, Hippocampus, Melatonin, Peptide Fragments, Sclera, tau Proteins