Depression duration but not age predicts hippocampal volume loss in medically healthy women with recurrent major depression.

This study takes advantage of continuing advances in the precision of magnetic resonance imaging (MRI) to quantify hippocampal volumes in a series of human subjects with a history of depression compared with controls. We sought to test the hypothesis that both age and duration of past depression would be inversely and independently correlated with hippocampal volume. A sample of 24 women ranging in age from 23 to 86 years with a history of recurrent major depression, but no medical comorbidity, and 24 case-matched controls underwent MRI scanning. Subjects with a history of depression (post-depressed) had smaller hippocampal volumes bilaterally than controls. Post-depressives also had smaller amygdala core nuclei volumes, and these volumes correlated with hippocampal volumes. In addition, post-depressives scored lower in verbal memory, a neuropsychological measure of hippocampal function, suggesting that the volume loss was related to an aspect of cognitive functioning. In contrast, there was no difference in overall brain size or general intellectual performance. Contrary to our initial hypothesis, there was no significant correlation between hippocampal volume and age in either post-depressive or control subjects, whereas there was a significant correlation with total lifetime duration of depression. This suggests that repeated stress during recurrent depressive episodes may result in cumulative hippocampal injury as reflected in volume loss.

The association of umbilical cord complications and variable decelerations with acid-base findings.

Variable decelerations during the last 2 hours of labor were associated with an abnormally positioned umbilical cord at delivery in 52% of cases. In cases where an abnormally positioned umbilical cord was seen at delivery, 89% had been preceded by variable decelerations. Cord compression resulted in an A-V difference in pH that was significantly increased when compared to a control group. This was mainly due to a decrease in the pH of the umbilical artery. The pathophysiology of cord compression is discussed.