Story here — medscape.com/viewarticle/571198
(Google “Low Testosterone Levels Linked With Higher Risk for Depression” and click first result if that link is inaccessible).
March 10, 2008 — Researchers have uncovered a link between low free testosterone levels and depression. Their study, which appears in the March issue of the Archives of General Psychiatry, shows that older men with abnormally low free testosterone levels, or hypogonadism, were, on average, 271% more likely to display clinically significant signs of depression than men with higher testosterone levels.
“Importantly, these results could not be explained by increasing age, education level, smoking, obesity or poor physical health — all factors that are known to dampen testosterone and are associated with depression,” said lead author Osvaldo P. Almeida, MD, PhD, director of research, Western Australian Centre for Health and Ageing, and professor and chair of geriatric psychiatry, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, Australia.
…
“The findings of this study are compelling in suggesting a causal relationship between low free testosterone and depression in older men,” Dr. Almeida told Medscape Psychiatry in an email. “The association is biologically plausible; there is evidence from lab work that testosterone may increase the bioavailability of serotonin and noradrenaline in the brain and this could explain its antidepressogenic effect.”
He stressed that the association between free testosterone levels and depression is a “risk” association rather than a cause-consequence effect. "Not all older men with depression are hypogonadal, and not all hypogonadal men have depression. But there is a dramatic increase in the risk of depression among hypogonadal men."
This study was also covered at the BBC News website ( news.bbc.co.uk/2/hi/health/6723723.stm ).
"A previous study of 800 men over the age of 50 found that [b]those with low levels of testosterone had a 33% increased risk of death over an 18-year period than those with higher levels.
They appeared significantly more likely to have a cluster of risk factors associated with cardiovascular disease and diabetes."[/b]
…
"Professor Stafford Lightman, a hormone expert at the University of Bristol, said testosterone potentially had many small effects which could raise the risk of depression. For instance, low levels had been linked to poor cognitive performance."
As if we all needed further examples of the hazardous side effects of Propecia.