(the link is behind a paygate for me, search google news for dimpna and you should be able to click right in)
The article itself seems to lean more towards the increase in diagnosis but there is also a socioeconomic side. Money in a society does many things.
A prosperous society enables education which in some circumstances enables power which corrupts, but prosperity also can diminish empathetic ability, especially in those born into fortunate circumstances (see affluenza). In wealthy societies, fortune (even lower middle class fortune that is wealth compared to the working poor) also creates a special kind of stress in the form of tall poppy-eque fears.