Medically reviewed by Dr. Kimberly Langdon Cull, M.D. on August 5, 2023
This study found that patients with multiple sclerosis and neuromyelitis optica spectrum disorder have an increased risk of all forms of dementia.
Both neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS) patients exhibit cognitive impairment; however, the risk of dementia in these patients is not established. This study, published in the journal Frontiers in Neuroscience, estimated the dementia risk in NMOSD and MS patients.
A total of 1347 MS patients with 6735 matched controls and 1460 NMOSD patients with 7300 matched controls were included. In the MS and NMOSD groups, 41.9% and 33.6% of the participants were males, respectively. The comorbidities included dyslipidemia, diabetes mellitus, and hypertension.
Dementia Risk in NMOSD and MS Patients
In the MS group, the incidence of any type of dementia was 17.08/1000 person-years compared to 7.36 in matched controls; the incidence of vascular dementia was 2.54/1000 person-years compared to 0.68 in matched controls; and the incidence of Alzheimer’s disease was 13.19/1000 years compared to 6.03 in matched controls. On the contrary, in the NMOSD group, the incidence of any type of dementia was 9.04/1000 person-years compared to 4.56 in matched controls; the incidence of vascular dementia was 1.64/1000 person-years compared to 0.53 in matched controls; and the incidence of Alzheimer’s disease was 6.25/1000 years compared to 3.55 in matched controls.
Differences in the Dementia Incidence in MS and NMOSD Patients
While the risk for vascular dementia was similar across the NMOSD and MS patients, the NMOSD patients had a lesser incidence of Alzheimer’s disease and any type of dementia than MS patients.
Risk of Dementia in Subgroups
The relative risk of dementia in NMOSD and MS patients was higher and more pronounced in patients without hypertension compared to patients with hypertension and in patients between the ages of 40 and 64 years compared to patients aged > 65 years. The same trend was evident in the higher risk of Alzheimer’s in NMOSD and MS patients. There was a statistically significant difference in the relative vascular dementia risk in subgroups of NMOSD and MS patients.
This study concluded that the risk of dementia increased in both NMOSD and MS; however, the risk was relatively higher in MS compared to NMOSD patients.
Cho, E. B., Jung, S. Y., Jung, J., Yeo, Y., Kim, H. J., Han, K., Shin, D. W., & Min, J. (2023). The risk of dementia in multiple sclerosis and neuromyelitis optica spectrum disorder. Frontiers in Neuroscience, 17. https://doi.org/10.3389/fnins.2023.1214652