A new study estimates that about 38 percent of Europeans, or 165 million people, have some type of mental illness and that most are going untreated.
The experts surveyed more than 90 different problems, from attention deficit disorders in children to dementia in Alzheimer's patients. Rates of mental disorders didn't appear to be rising, compared to a similar study in 2005.
The most common problems included anxiety disorders, insomnia, depression, alcohol and drug dependence and dementia. Experts estimated only one-third of people receive treatment.
The study was published Tuesday by the European College of Neuropsychopharmacology.