Depression is on the rise in the United States, according to researchers at Columbia University’s Mailman School of Public Health and the CUNY Graduate School of Public Health and Health Policy. From 2005 to 2015, depression rose significantly among Americans age 12 and older with the most rapid increases seen in young people.

The findings appeared online in the journal Psychological Medicine.

This is the first study to identify trends in depression by gender, income, and education over the past decade.

“Depression appears to be increasing among Americans overall, and especially among youth,” said Renee Goodwin, PhD, of the Department of Epidemiology, Mailman School of Public Health, who led the research. “Because depression impacts a significant percentage of the U.S. population and has serious individual and societal consequences, it is important to understand whether and how the prevalence of depression has changed over time so that trends can inform public health and outreach efforts.”

The results show that depression increased significantly among persons in the U.S. from 2005 to 2015, from 6.6% to 7.3%. Notably, the rise was most rapid among those ages 12 to 17, increasing from 8.7% in 2005 to 12.7% in 2015.

Data were drawn from 607,520 respondents to the National Survey on Drug Use and Health, an annual U.S. study of persons ages 12 and over. The researchers examined the prevalence of past-year depression annually among respondents based on DSM-IV criteria.

The increase in rates of depression was most rapid among the youngest and oldest age groups, whites, the lowest income and highest income groups, and those with the highest education levels. These results are in line with recent findings on increases in drug use, deaths due to drug overdose, and suicide.

“Depression is most common among those with least access to any health care, including mental health professionals. This includes young people and those with lower levels of income and education,” noted Goodwin. “Despite this trend, recent data suggest that treatment for depression has not increased, and a growing number of Americans, especially socioeconomically vulnerable individuals and young persons, are suffering from untreated depression. Depression that goes untreated is the strongest risk factor for suicide behavior and recent studies show that suicide attempts have increased in recent years, especially among young women.”

Depression frequently remains undiagnosed, yet it is among the most treatable mental disorders, noted the researchers. “Identifying subgroups that are experiencing significant increases in depression can help guide the allocation of resources toward avoiding or reducing the individual and societal costs associated with depression,” said Goodwin.