Prevalence of Brain Arteriovenous Malformations in First-Degree Relatives of Patients With a Brain Arteriovenous Malformation

For those that have AVMs.
http://stroke.ahajournals.org/content/45/11/3231.abstract?etoc

1. Janneke van Beijnum, MD, PhD;
2. H. Bart van der Worp, MD, PhD;
3. Ale Algra, MD, PhD;
4. W. Peter Vandertop, MD, PhD;
5. René van den Berg, MD, PhD;
6. Patrick A. Brouwer, MD;
7. Jan Willem Berkelbach van der Sprenkel, MD, PhD;
8. L. Jaap Kappelle, MD, PhD;
9. Gabriël J.E. Rinkel, MD, FRCPE;
10. Catharina J.M. Klijn, MD, PhD

+ Author Affiliations

1. From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (J.v.B., H.B.v.d.W., A.A., J.W.B.v.d.S., L.J.K., G.J.E.R., C.J.M.K.), and the Julius Centre for Health Science and Primary Care (A.A.), University Medical Center Utrecht, Utrecht, The Netherlands; Departments of Neurosurgery (W.P.V.) and Radiology (R.v.d.B.), Neurosurgical Center Amsterdam, VU University Medical Center and Amsterdam Medical Center, Amsterdam, The Netherlands; and Departments of Neurosurgery (J.v.B.) and Radiology (P.A.B.), Leiden University Medical Center, Leiden, The Netherlands.

1. Correspondence to Janneke van Beijnum, MD, PhD, Department of Neurosurgery, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands. E-mail J.vanBeijnum@gmail.com

Abstract

Background and Purpose—It is uncertain whether familial occurrence of brain arteriovenous malformations (BAVMs) represents coincidental aggregation or a shared familial risk factor. We aimed to compare the prevalence of BAVMs in first-degree relatives (FDRs) of patients with BAVM and the prevalence in the general population.

Methods—We sent a postal questionnaire to 682 patients diagnosed with a BAVM in 1 of 4 university hospitals to retrieve information about the occurrence of BAVMs among their FDRs. We calculated a prevalence ratio using the BAVM prevalence among FDRs and the prevalence from a Scottish population-based study (93 per 628 788 adults). A prevalence ratio of ≥9 with a lower limit of the 95% confidence interval of 3 was considered indicative of a shared familial risk factor.

Results—Informed consent was given by 460 (67%) patients, who had 2992 FDRs. We identified 3 patients with a FDR with a BAVM, yielding a prevalence ratio of 6.8 (95% CI, 2.2–21).

Conclusions—The prevalence of BAVMs in FDRs of patients with a BAVM was increased but did not meet our prespecified criterion for a shared familial risk factor. In combination with the low absolute risk of a BAVM in FDRs, our results do not support screening of FDRs for BAVMs.