Clinical spectrum of CADASIL and the effect of cardiovascular risk factors on phenotype: study in 200 consecutively recruited individuals

Abstract

Background and purpose: Cerebral Autosomal-Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is an inherited arteriopathy with clinical features that include recurrent lacunar stroke, migraine, and cognitive impairment. For reasons that remain unclear, there is great variability in the clinical expression of CADASIL, both between and within families. This study examined the clinical phenotype as well as any associations with risk factors and genotype in a large, prospective cohort.

Methods: Two hundred symptomatic individuals from 124 families were recruited as part of a UK prevalence study of CADASIL and were seen subsequently in a national referral clinic. All were assessed by a standardized questionnaire and examination.

Results: Mean age at assessment was 47.7 years and was 33.6 years at symptom onset. Migraine, usually with aura, was the most prevalent feature, affecting 75% of individuals. More than half had a history of stroke, with a mean age at onset of 46 years. Hypertension (odds ratio=2.57, P=0.007) and pack-years of smoking (odds ratio=1.07, P=0.001) were associated with an increased risk of stroke. A history of stroke was a significant risk factor for both dementia and disability. Mutations clustered in exon 4 of the NOTCH3 gene, which contained > or = 71.4% of familial mutations. Four previously unreported mutations were found (T697C, C1279T, G1370C, and C1774T). No associations were identified between genotype and clinical phenotype.

Conclusions: Our data suggest that cardiovascular risk factors may modulate the clinical expression of CADASIL. The associations with hypertension and smoking suggest that risk factors should be treated aggressively in patients with CADASIL.