Neurofibromatosis type 1 and chronic neurological conditions in the United States: an administrative claims analysis.

Purpose: Neurofibromatosis type 1 has been linked to several neurological conditions, including epilepsy, Parkinson disease, headache, multiple sclerosis, and sleep disturbances, predominantly through case reports and patient series that lack comparison groups. Our objective was to assess whether specific neurological conditions occur more frequently in individuals with neurofibromatosis type 1 versus those without neurofibromatosis type 1.

Methods: We used the 2006-2010 MarketScan Commercial Claims and Encounters database to examine associations between neurological conditions and neurofibromatosis type 1. The neurofibromatosis type 1 group was identified through ≥2 International Classification of Diseases, Ninth Revision, Clinical Modification neurofibromatosis codes (237.70, 237.71) occurring ≥30 days apart or one inpatient neurofibromatosis code. A nonneurofibromatosis type 1 comparison group was frequency matched to the neurofibromatosis type 1 group on age and enrollment length at a 10:1 ratio. Unconditional logistic regression was employed to calculate adjusted odds ratios and 95% confidence intervals for associations between neurofibromatosis and neurological conditions.

Results: Compared with the nonneurofibromatosis type 1 group (n = 85,790), the neurofibromatosis type 1 group (n = 8,579) had significantly higher odds of health insurance claims for epilepsy (odds ratio: 7.3; 95% confidence interval: 6.4-8.3), Parkinson disease (odds ratio: 3.1; 95% confidence interval: 1.3-7.5), headache (odds ratio: 2.9; 95% confidence interval: 2.6-3.1), multiple sclerosis (odds ratio: 1.9; 95% confidence interval: 1.2-2.9), and sleep disturbances/disorder (odds ratio: 1.4; 95% confidence interval: 1.2-3.6).

Conclusion: This large study provides strong evidence for positive associations between several neurological conditions and neurofibromatosis type 1.