Buried deep in the New York Time's article is the possible cause:
At the moment, the prime suspect is the skyrocketing use — and abuse — of prescription drugs. During the same five-year period included in the study, there was a staggering increase in the total number of drug overdoses, both intentional and accidental, like the one that recently killed the 28-year-old actor Heath Ledger. Illicit drugs also increase risky behaviors, C.D.C. officials point out, noting that users’ rates of suicide can be 15 to 25 times as great as the general population.This seems plausible to me. There really isn't any understanding of how the meds affect people going on and off of them and mixing them. And then there is the fact that the Boomers may have the most difficult time with aging of any generation.