Reduced white matter integrity in sibling pairs discordant for bipolar disorder

Emma Sprooten, Margaret S. Brumbaugh, Emma E.M. Knowles, D. Reese McKay, John Lewis, Jennifer Barrett, Stefanie Landau, Lindsay Cyr, Peter Kochunov, Anderson M. Winkler, Godfrey D. Pearlson, David C. Glahn

Research output: Contribution to journalArticlepeer-review

42 Scopus citations


Objective: Several lines of evidence indicate that white matter integrity is compromised in bipolar disorder, but the nature, extent, and biological causes remain elusive. To determine the extent to which white matter deficits in bipolar disorder are familial, the authors investigated white matter integrity in a large sample of bipolar patients, unaffected siblings, and healthy comparison subjects. Method: The authors collected diffusion imaging data for 64 adult bipolar patients, 60 unaffected siblings (including 54 discordant sibling pairs), and 46 demographically matched comparison subjects. Fractional anisotropy was compared between the groups using voxel-wise tract-based spatial statistics and by extracting mean fractional anisotropy from 10 regions of interest. Additionally, intraclass correlation coefficients were calculated between the sibling pairs as an index of familiality. Results: Widespread fractional anisotropy reductions in bipolar patients (>40,000 voxels) and more subtle reductions in their siblings, mainly restricted to the corpus callosum, posterior thalamic radiations, and left superior longitudinal fasciculus (>2,000 voxels) were observed. Similarly, region-of-interest analysis revealed significant reductions in most white matter regions in patients. In siblings, fractional anisotropy in the posterior thalamic radiation and the forceps was nominally reduced. Significant between-sibling correlations were found for mean fractional anisotropy across the tract-based spatial statistic skeleton, within significant clusters, and within nearly all regions of interest. Conclusions: These findings emphasize the relevance of white matter to neuropathology and familiality of bipolar disorder and encourage further use of white matter integrity markers as endophenotypes in genetic studies.

Original languageEnglish
Pages (from-to)1317-1325
Number of pages9
JournalAmerican Journal of Psychiatry
Issue number11
StatePublished - 1 Nov 2013
Externally publishedYes


Dive into the research topics of 'Reduced white matter integrity in sibling pairs discordant for bipolar disorder'. Together they form a unique fingerprint.

Cite this