Mental health in big cities.

DOI:10.1097/YCO.0000000000000599 There is no question that the world is becoming more urbanized, with both positive and negative for health and mental health. City life is surfaced by many jobs and educational opportunities, but there is also the possibility of violence and unforeseen accidents. Modern life is matched by increasing levels of immigration, concentration of air pollution, facilitating policies for substance abuse and the widespread use of internet and smartphones replacing human close contact. On top of the increasing immigration moves and the risk of new epidemics, on the social side it has seen the return of nationalism and reinforcing sexist and stigma against women, ethnic groups and sex minorities in some countries. How can all these changes affect a population’s mental health in big cities? Editing a volume on this field is an exciting opportunity to hear from investigators around the globe on their feelings and views about this contemporary topic in psychiatry. This supplement will cover the main psychiatric disorders occurring in modern societies, such as depression, Post-traumatic stress disorder (PTSD), schizophrenia, substance abuse and internet addiction. It will question how modern behaviors are inducing new diseases, the role of the educational system in the promotion and prevention of mental health and a study of the role of traditional healers in places, where there is a scarcity of mental health professionals, particularly in Africa. The available epidemiological evidence suggests that the prevalence of depression has increased since the last century, especially in the last few decades, with recent cohorts showing an increased onset of depression and a consequent increase in risk throughout life. Competitive environments, social inequality and loneliness are the main factors of modern Western culture related to the rising rates of mental disorders, including depression. Humans have become overfed, malnourished and sedentary, with low exposure to sunlight; they are sleep deprived and living in competitive environments and social isolation. Early trauma wherever it happens will have a pleiotropic effect on depression, PTSD and psychosis, as alteration of inflammatory markers can affect neurocircuits and therefore making humans more vulnerable to develop severe psychiatric disorders in adulthood.