Prevalence of hippocampal enlarged perivascular spaces in a sample of patients with hypertension and their relation with vascular risk factors and cognitive function

Objectives The clinical importance of hippocampal enlarged perivascular spaces (H-EPVS) remains uncertain. We aimed to study their association with vascular risk factors, cognitive function and mild cognitive impairment (MCI). Methods Data were obtained from the ISSYS (Investigating Silent Strokes in hYpertensives, a magnetic resonance imaging Study) cohort, which is a prospective study of patients with hypertension aged 50-70 with no prior stroke or dementia. Participants were clinically evaluated and underwent a cognitive screening test, Dementia Rating Scale-2, which includes five cognitive subscales (attention, initiation/perseveration, conceptualisation, construction and memory). Besides, they were diagnosed with MCI or normal ageing following standard criteria. H-EPVS were manually counted on brain MRI according to a previous scale and defined as extensive when H-EPVS count was >= 7 (upper quartile). Multivariate models were created to study the relationship between H-EPVS, vascular risk factors and cognitive function. Results 723 patients were included; the median age was 64 (59-67) and 51% were male. Seventy-two patients (10%) were diagnosed with MCI and 612 (84.6%) had at least 1 H-EPVS. Older age (OR per year=1.04, 95% CI 1.01 to 1.08) and poor blood pressure treatment compliance (OR=1.50, 95% CI 1.07 to 2.11) were independently associated with extensive H-EPVS. Regarding cognitive function, H-EPVS were independently and inversely correlated with verbal reasoning (beta=-0.021, 95% CI -0.038 to -0.003). No association was found between H-EPVS and MCI. Conclusions H-EPVS are a frequent finding in patients with hypertension and are associated with ageing and poor hypertension treatment compliance. Besides, H-EPVS are associated with worse verbal reasoning function.