São Paulo: urbanization and mental disease

It was published this February in PLOS one  the result of a survey coordinated by WHO which demonstrated that 30 % of the 5037 persons interviewed  have had some kind of mental disease in the last year, being the highest prevalence observed in surveys conducted in others 25 big cities around the world (the highest prevalence was observed in the USA - 26 %). Extrapolating this result to São Paulo's population we can estimate that around 7 million people could be mentally affected in one of the biggest cities of the World. These numbers are very disturbing since the urbanization phenomena is almost complete in Brazil, where up to 90 % of the population live in a city. According to the article, the worst fear of the participating of the survey was violence, others problems related to the decontrolled urbanization also interfere with mental sanity of cities inhabitants such as pollution, high degree of noise, bad public transport etc. The survey also associated these variables with the type of  mental disorder referred. Bellow the link to the article, which I believe that contributes enormously to the discussions tha will take place in Rio de Janeiro during the Rio +20.

Link: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0031879