Chloé Johnson, 22, has been feeling hopeless lately.

She’s struggling to focus on classes at her local community college in Dallas while also working full-time, making $18 an hour as a receptionist.

Her car broke down, so the $500 that she had managed to save will now go toward a down payment for a used vehicle.

And she was recently passed over for a promotion.

“Right now it just feels, like, very suffocating to be in this position,” said Ms. Johnson, who was diagnosed last year with bipolar II disorder, depression and A.D.H.D. “I’m not getting anywhere or making any progress.”

It’s an endless loop: Ms. Johnson’s mental health has worsened because of her financial difficulties and her financial problems have grown, partly because of the cost of mental health treatment but also because her disorders have made it more difficult to earn a college degree that could lead to a more lucrative job.

“I’ve failed several classes,” she said. “I burn out really easily, so I just give up.”

The mental health of adolescents and young adults has been on the decline and it’s partly because of “harmful megatrends” like financial inequality, according to a new report published on Tuesday in the scientific journal The Lancet Psychiatry. The global trends affecting younger generations also include wage theft, unregulated social media, job insecurity and climate change, all of which are creating “a bleak present and future for young people in many countries,” according to the authors.

Why focus on global trends?

The report was produced over the course of five years by a commission of more than 50 people, including mental health and economic policy experts from several continents and young people who have experienced mental illness.