The months-long social turmoil in Hong Kong is taking a toll on people's mental health.  

One in five of Hong Kong adults have reported symptoms of probable depression or post-traumatic stress disorder, also known as PTSD, after unrest broke out in the city since last June, according to a 10-year study published recently in the medical journal Lancet.  

The incidence rate of depression in Hong Kong was around two percent back in 2009, and it has gone up five times to 11.2 percent by the end of November 2019, Professor Gabriel Leung, who co-led the study in the University of Hong Kong, told CGTN. 

And the rate of PTSD has gone up 12.8 percent during the same period. "So this is definitely abnormal," he noted. 

When asked to what extent the protests related to this, Leung replied that he couldn't think of any other reason, even though he couldn't say it's 100 percent definite.  

"I cannot  – as a doctor and as a scientist – think of any other explanation, which would be so synchronous. That is, it shows the timing matches so perfectly, and it affects everybody in society similarly, other than the social unrest," he said. 

"So I'm pretty sure that this is what has caused the psychiatric mobility that we have measured," he told CGTN.  

"Regardless of your political belief, whether you support or you are in opposition to the movement, regardless of whether you're young or old, regardless of whether you are rich or poor, everybody suffers, similarly," he pointed out. 

What's more worrying, only less than half of the people with probable depression or PTSD said they would seek professional counseling or advice or care when asked about it, the study found.  

"In some cases, we detected suicidal ideation. That is, they are thinking about harming themselves, putting an end to their own lives," he said.  

"What I really, really worry about is that we do not have the capacity in the health care or social care system to deal with this huge mental health burden. Hong Kong has got a shortage of these professionals, even during peace time," he added.  

(CGTN's Cao Qingqing contributed to the story.)