Amygdala volume in patients receiving chronic corticosteroid therapy.

BACKGROUND: Hippocampal volume reduction and declarative memory deficits are reported in humans and animals exposed to exogenous corticosteroids. The amygdala is another brain structure involved in the stress response that has important interactions with the hypothalamic-pituitary-adrenal axis. To our knowledge, no studies in animals or humans have examined the impact of exogenous corticosteroid administration on the amygdala. We assessed amygdala volume in patients receiving chronic prescription corticosteroid therapy and control subjects with similar medical histories not receiving corticosteroids. METHODS: Fifteen patients on long-term prednisone therapy and 13 control subjects of similar age, gender, ethnicity, education, height, and medical history were assessed with magnetic resonance imaging. Amygdala volume was manually traced and compared between groups using a two-way analysis of variance (ANOVA). Correlations between amygdala volume, age, and corticosteroid dose/duration were assessed using Pearson's correlation coefficient. RESULTS: Compared with control subjects, corticosteroid-treated patients had significantly smaller amygdala volumes. Right amygdala volume correlated significantly with age in control subjects and with duration of corticosteroid therapy in patients. CONCLUSIONS: Patients receiving chronic corticosteroid therapy had smaller amygdala volumes than control subjects that correlated with duration of corticosteroid therapy. These findings suggest that corticosteroid exposure may be associated with changes in the amygdala as well as hippocampus.

Effects of chronic prednisone therapy on mood and memory.

BACKGROUND: In animals, stress and corticosteroids can be associated with both reversible and irreversible changes in the hippocampus. Changes in memory and hippocampal structure, perhaps in part due to cortisol elevations, are reported in some patients with mood disorders. Minimal data are available on the effects of long-term exposure to corticosteroids on the human hippocampus. We previously reported greater depressive symptom severity, poorer memory and smaller hippocampal volumes in patients with asthma or rheumatic diseases receiving long-term prednisone therapy than in controls. METHODS: In this report, patients and controls were assessed a mean of 4 years after the first assessment to determine if depressive and manic symptoms and cognition remained stable, improved or worsened. Seven prednisone-treated patients and six controls were identified and agreed to reassessment with psychiatric symptom and neurocognitive measures. Follow-up MRIs for hippocampal volume analysis were available for two prednisone-treated participants. RESULTS: With the exception of an increase in depressive symptoms in those receiving prednisone, participants and controls did not show significant change in mood or cognition from the initial assessment. One participant discontinued prednisone and showed improvement in psychiatric symptoms and cognition. Hippocampal volumes were available in two prednisone-treated participants and showed inconsistent findings. LIMITATIONS: A limitation is the small sample size. CONCLUSIONS: Our findings, although preliminary in nature, suggest that long-term prednisone therapy is associated with initial changes in mood, memory and hippocampal volume that appear to stabilize over time.

Mean noise amounts in level II vs level III neonatal intensive care units.

PURPOSE: To compare mean noise amounts in Level II NICUs with those in Level III NICUs after controlling statistically for the number of infants per unit. STUDY DESIGN: A between-group design was used in measuring noise amounts. SAMPLE: Noise amounts were sampled using a central site procedure during two time periods of approximately 25 minutes each (total time approximately 50 minutes) in five Level II NICUs and seven Level III NICUs in Colorado. MAIN OUTCOME VARIABLE: Average noise amounts (in dB) from two time periods of approximately 25 minutes each (total time approximately 50 minutes). RESULTS: Mean noise amounts were significantly higher in Level III NICUs (mean = 54.89 dB) than in Level II NICUs (mean = 49.07 dB). This result remained statistically significant even after correcting statistically for total number of babies present in each NICU during noise measurements.