White matter hyperintensities and their association with suicidality in major affective disorders: a meta-analysis of magnetic resonance imaging studies.

INTRODUCTION: Individuals who have deep and periventricular white matter hyperintensities may have a higher risk for suicidal behavior. There are mixed results in the literature regarding whether unipolar or bipolar patients who have attempted suicide have more deep white matter hyperintensities (DWMH) or periventricular hyperintensities (PVH) relative to those who have no history of suicide attempts.
METHODS: A meta-analysis of studies examining white matter hyperintensities (WMH) in mood disorder patients with and without a history of suicide attempts was performed.
RESULTS: Four studies, including a total of 173 patients who attempted suicide and 183 who did not attempt suicide, were included. A significantly higher number of attempters were found to have WMH than non-attempters. Unipolar depressed patients who had attempted suicide had 1.9 times more DWMH and 2.1 times more PVH than those who did not. Bipolar patients who had attempted suicide had 5.4 times more PVH than those who had not. Taken together, unipolar and bipolar patients who had attempted suicide had 2.8 times more DWMH and 4.5 times more PVH than those who had never attempted suicide.
CONCLUSION: These findings raise the possibility that WMH are biological substrates of symptoms that lead to suicidal behavior.