Increased Risk of Cerebrovascular Disease Among Patients With Neurofibromatosis Type 1: Population-Based Approach

Background and purpose: Although neurofibromatosis type 1 (NF1) may be associated with an incompletely understood vasculopathy, relative odds of stroke in this population is not known.

Methods: Using the 1998 to 2009 US Nationwide Inpatient Sample, we performed a case-control study matching cases of NF1 to controls without such a diagnosis. We then compared the odds of stroke between the 2 groups. We used multivariable logistic regression to adjust for known or suspected confounders.

Results: NF1 was associated with younger mean age at the time of stroke (41 versus 48) and a lower prevalence of stroke risk factors among adult patients. Pediatric patients with NF1, however, were more likely to have hypertension. Patients with NF1 were significantly more likely to be diagnosed with any stroke (odds ratio, 1.2; P<0.0001) than the general population. The odds of intracerebral hemorrhage were greatest among hemorrhagic stroke types analyzed (odds ratio, 1.9; P<0.0001). In the pediatric NF1 population, the odds of intracerebral hemorrhage were more dramatically elevated (odds ratio, 8.1; P<0.0001). The odds of ischemic stroke were also increased with NF1 in the pediatric (odds ratio, 3.4; P<0.0001) but not in the adult population.

Conclusions: When compared with the general population, the odds of any type of stroke are significantly increased for patients with NF1, both adult and pediatric. This risk is most notable for hemorrhagic strokes although it is also increased for ischemic strokes in children. Physicians should be aware of the increased risk of stroke in this population, and consider stroke as a potential cause of new neurological symptoms.