Oddly enough, Part 1 of the CBC documentary that I linked to above was on again last night. It again, for me, put the subject of this thread in a totally different light.

Changes in our sleep patterns, that are not linked to some underlying medical problem, are normal and natural as we age. Expecting the constant uninterrupted night's sleep of our youth is unrealistic. But you do have a choice. Medicate, with all it's ramifications or embrace the change and don't worry about it.