Deep White Matter Abnormalities on MRI Are Linked to Winter Births in Bipolar Patients

DEEP

WHITE MATTER ABNORMALITIES ON MRI ARE LINKED TO WINTER BIRTHS IN

BIPOLAR PATIENTS

P.B. Moore*, A.

H. Young, I.N. Ferrier. Department Psychiatry, Newcastle

University, Newcastle Upon Tyne, United Kingdom

Introduction: Recently it

has been established that bipolar patients, show winter/early

spring birth excess. Although white matter abnormalities are

found three times more frequently in bipolars than controls, the

neuropathology and clinical correlates of the abnormalities

remain poorly understood.

Method: 7mm thick axial T2

weighted (TR=2300, TE=25, 100ms) and proton

density scans were examined from 79 bipolar patients (DSM IV; 15

males, 64 females, age 35.4±8.6yrs)

for the presence of deep subcortical (DWML) and periventricular

white matter lesions( PVWML). The birth season of patients

showing DWMLs or PVWMLs were compared with those of the general

population.

RESULTS: Thirteen subjects

exhibited DWMLs, of whom 9 were born in the months Jan-March, a

frequency significantly different from the normal population (c 2=14.49,

DF=3, p=0.003) and from bipolars without DWMLs ((c 2=10.77,

DF=3, p=0.014). Seven of these patients had remained symptomatic

for 2 years despite adequate therapy.

COMMENT: Birth season,

illness outcome and DWMLs appear to be closely linked. DWMLs may

represent a marker of an in-utero toxic or infective insult.