Relationships between mood and estradiol (E2) levels in Alzheimer's disease (AD) patients

This study investigates the relationship between mood and estradiol (E2) levels and assesses the prevalence of mood symptoms in Alzheimer's disease (AD) patients compared to healthy elderly controls. Fifty-two AD patients (26 men, 23 estrogen non-using women and three estrogen-using women), mean age 76.2 years, were recruited and assessed with the Geriatric Depression Scale (GDS), a test of mood, and a radioimmunoassay measure of E2 levels at the time of testing. The AD patients were compared to a control group of age and gender-matched healthy elderly men and women estrogen-users and non-users. No differences were found between the AD patients and the controls in overall E2 levels, but, as expected, the women estrogen-users in both the AD and control groups had higher E2 levels than the men and the female estrogen non-users. Both groups of men had higher E2 levels than the estrogen non-using women. There was a significant negative correlation between E2 levels and GDS scores in the full sample, which was particularly strong in the estrogen-using women. This indicates that those subjects with higher E2 levels had less mood symptomatology. Overall, mood scores in the AD patients were higher than in the healthy controls, indicating higher levels of depressive symptomatology; the highest depression scores occurred in the AD women who were estrogen non-users. This suggests that depressive symptoms are common in AD patients, and that women with AD who are not taking estrogen replacement may be especially vulnerable to depression.