Studies have long shown a link between depression and AD, and some of the newest (last couple years) seem to be showing that depression may actually be causing

Studies have long shown a link between depression and AD, and some of the newest (last couple years) seem to be showing that depression may actually be causing and accelerating AD as opposed to just being a comorbidity. In the same vein we have IBS, a condition which can sometimes be treated with antidepressants. Fascinating stuff.