In adults between 72 and 92 years of age, severe perivascular dilatation (PVS) pathology predicts an increased risk of cognitive decline and dementia, according to study results published in Neurology.
The study included 414 community elderly adults between the ages of 72 and 92 years (mean age 79.8 years) who were part of the Sydney Memory and Aging Population Study. Participants underwent cognitive assessments and 3T MRI imaging and were screened for consensus diagnoses of dementia at baseline and every 2 years for up to 8 years.
The researchers of the study counted the number of PVS in 2 representative layers in the basal ganglia (BG) and in the Centrum semiovale (CSO) and defined a severe PVS pathology as the top quartile. They also examined the effects of severe PVS in BG or CSO regions, both regions, and in patients with severe BG and / or severe CSO-PVS.
Approximately 38% (n = 157) of the study participants had severe PVS pathology in both regions, while 7% (n = 32) had severe pathology in both regions, 22% (n = 90) had severe BG-PVS pathology and 24% (n = 99) had severe CSO-PVS pathology.
Participants with severe BG-PVS had a significantly greater volume of white matter hyperintensities (P = 0.004) and had significantly more frequent gaps (17% versus 6%; P = 0.002) and multiple cerebral microbleeds (23% versus 9%); P = 0.002) compared to participants with no / mild BG-PVS.
In an analysis adjusted for all covariates, participants with severe PVS pathology showed a faster decline in global cognition in both regions compared to participants with less severe pathology (P = 0.020).
Participants with severe PVS pathology in both regions were also more likely to develop dementia during the 8-year follow-up period (odds ratio) [OR]2.91; 95% CI, 1.43-5.95; P = 0.003). In addition, the presence of severe PVS pathology was evident either after 4 years (OR 4.75; 95% CI 1.51-14.95; P = 0.008) or after 6 years (OR 5.44; 95% CI) associated with a higher risk of dementia 1.31-22.61; P = 0.020) across all groups.
The limitations of this study included the lack of long-term follow-up and the availability of detailed cognitive data for only 4 years compared to the 8-year follow-up period.
Based on their results, the researchers concluded that “further research into the etiology and consequences of PVS pathology is needed as PVS may be an important potential biomarker for the early diagnosis, prognosis and subtyping of dementia”.
Paradise M, Crawford JD, Lam BCP, et al. The association of enlarged perivascular spaces with cognitive decline and incident dementia. Published online January 27, 2021. Neurology. doi: 10.1212 / WNL.0000000000011537