One would expect the rich to use more and better drugs, since they have more money to buy them with.
The story doesn't look very deeply into the situation. People of all kinds die all the time in situations where drugs (legal and illegal) may be a factor. Drugs, including illegal ones, may also save people's lives, health, and minds by enabling them to cope with suffering and stress. The true villain appears to be work, but only a scientific approach could tell us -- not journalistic anecdote- and rumor-mongering.