Nearly half of US youths suffer from a psychiatric disorder, from alcohol dependency to depression, but few seek treatment, according to a study published in this week’s Archives of General Psychiatry. For the study, US researchers analyzed data from more than 5,000 respondents, aged 19 to 25, who took part in the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions, which was conducted by the U.S. Census Bureau and the National Institute on Alcohol Abuse and Alcoholism.

During the study, students and young adults who were not in college were questioned about their behaviour in the previous year. The interviews were based on information from the “Diagnostic and Statistical Manual of Mental Disorders,” a tool used by doctors to diagnose mental illness.

The study found that 45.8 percent of the 2,188 college students and 47.7 percent of the young adults not in college had one psychiatric disorder. The study has also found that fewer than 25 percent of college-aged Americans with mental problems get treatment. 20 percent of college students interviewed reported alcohol abuse and dependency. 18 percent of the group of college students suffered from obsessive-compulsive and paranoid disorders.

Among college students, the rate of mood disorders, such as depression and bipolar disorder, was 11 percent, compared to 12 percent for non-students, who were also most likely to report personality disorders and nicotine dependence. Non-students were more likely than students to receive treatment for alcohol and drug-use disorders.

Personality disorders, such as obsessive, anti-social and paranoid behaviours, were the second most common problem behind drug or alcohol abuse. Studies have shown that drinking problems have a very negative impact on mental health. Alcohol abuse and alcoholism can worsen existing conditions such as depression or anxiety.

About 8 percent in both groups had obsessive compulsive personality disorder, which can include an extreme preoccupation with details, rules, orderliness and perfectionism. Slightly more non-students had bipolar disorder – 5 percent versus 3 percent.

The study highlights the importance of screening and intervention programs on college and university campuses to reduce the number of young adults who suffer from mental health disorders. “The vast majority of disorders in this population can be effectively treated with evidence-based psychosocial and pharmacological approaches,” researchers at the New York State Psychiatric Institute said. However, long-term studies are needed to determine whether sustained treatment can improve outcomes.

Earlier this year, a nationwide survey has shown that more American teens who try drugs for the first time continue to use these drugs. Overall, from 2002 to 2007, the report found a decrease in the rates of adolescent substance abuse for almost every type of illegal drug, including marijuana, cocaine, LSD, Ecstasy as well as prescription drugs. The reports point to the association between substance abuse and mental health. 24.3 million Americans aged 18 or older experienced serious psychological distress.

Another study has found that there is a significantly greater use of antipsychotic drugs in U.S. than in Western Europe; the study found antipsychotic prevalence was 1.5 to 2.2 times greater in the U.S. than in the Netherlands and Germany.