Depression is a common problem among elderly people and can be linked with physical health problems and mental decline. However, some studies show that physical and intellectual problems can be reversed if people's depression is treated effectively. A trial of a new drug called duloxetine on 311 elderly people in Canada compared its effectiveness to a placebo. At the end of the eight-week trial those people taking duloxetine showed an improvement in their verbal learning and memory compared to those people taking a placebo. They were also less depressed and suffered from less pain than the placebo group. This was a rigorous study but it was partly funded by the Eli Lilly drugs company.
Raskin, Joel ... [et al] - Efficacy of duloxetine on cognition, depression, and pain in elderly patients with major depressive disorder : an 8-week, double-blind, placebo-controlled trial American Journal of Psychiatry 164(6), 900-909