Therapeutic Effects of Low-Level Laser Therapy on Cognitive Symptoms of Patients with Dementia: A Double-Blinded Randomized Clinical Trial.

Objective: To investigate the effects of low-level laser therapy (LLLT) as a new nonpharmaceutical approach to improve cognitive symptoms in patients with dementia. Background: Routine pharmacological treatment of dementia patients is inefficient and has considerable adverse effects. Recent attempts to develop nonpharmaceutical approaches are considered favorable for patients with dementia. Methods: Thirty-two patients with dementia were randomly divided into the same population of LLLT and sham groups. The LLLT group underwent transcranial LLLT, and the sham group received the same protocol with a zero-intensity laser. All patients in the two groups were evaluated using the minimental state examination (MMSE) and clinical dementia rating (CDR) tests at the time of admission as baseline at 2 and 6 weeks postintervention. Results: The rate of change of MMSE scores in sham and LLLT groups was 0.13 ± 0.96 and 2.31 ± 1.81 in week 2 ( p  = 0.00005) and also -0.25 ± 0.86 and 2.53 ± 1.73 in week 8 ( p  = 0.000003). In the LLLT group, the mean scores of CDR were 1.28 ± 0.71, 1.28 ± 0.71, and 1.25 ± 0.80 at baseline, week 2, and week 8 ( p  = 0.605 and p  = 0.742), respectively. The mean scores of CDR in the sham group were 1.69 ± 0.73, 1.75 ± 0.68, and 1.72 ± 0.82 at baseline, week 2, and week 8, respectively. Conclusions: These findings suggest that laser therapy could be a promising treatment modality and an adjunct to pharmacotherapy in dementia patients. Clinical Trial Registration: IRCT20191018045148N1 was obtained from the Iranian Registry of Clinical Trials (IRCT.ir).