A recent study by Chinese researchers found that Chinese submariners in the South China Sea are suffering from "serious" psychological disorders.
A little over one-fifth of surveyed sailors showed signs of mental health issues.
The operating environment, as well as the challenges of life aboard a submarine, put submariners at a higher risk for psychological issues.
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"One group of military personnel at high risk of mental health problems is the submarine force, especially in the South China Sea," five Chinese researchers affiliated with the Institute of Military Health Management at Naval Medical University in Shanghai wrote in an article published earlier this month in Military Medicine.
108 out of 511 surveys of Chinese submariners in the South China Sea showed signs of psychological disorders ranging from depression and anxiety to hostility, the study found.
The results were compared to mental health norms among male service members across the Chinese armed forces and were found to be "significantly higher."
"This study demonstrates for the first time that soldiers and officers in the submarine force in the South China Sea are facing mental health risks and suffering from serious psychological problems," the researchers concluded.
China claims the vast majority of the disputed South China Sea, and it has increased its naval patrols of the waterway over the years to reinforce its sovereignty claims.
"Studies have demonstrated that military maneuvers can produce psychological and physiological stress," the Chinese researchers explained, adding that life aboard a submarine can also lead to mental health issues.
They wrote that submariners, who tend to have higher rates of neuropsychiatric illness, "are confined to tiny living spaces and exposed to manufactured air and artificial light," and "the submarine environment entails prolonged isolation, which can involve 60 to 90 days of submerged cruising."
The study also found that sailors aboard nuclear submarines tended to be at a higher risk for psychological disorders.
Long overlooked in militaries around the world, mental health is an important part of determining the overall readiness of a force.
For China, psychological evaluations were not included as part of the military recruitment process until 2006, and mental health services for Chinese troops are still works in progress.
Recognizing that life aboard naval vessels can be challenging for sailors, the US Navy began embedding psychologists aboard aircraft carriers in the 1990s, and it saw a dramatic decrease in emergency evacuations and administrative separations for misbehavior.
This important program, known as the embedded Mental Health Program (eMHP), was later extended to additional surface vessels and appeared to be similarly effective.
An eMHP for the Navy's submarine force was piloted in 2013 in Norfolk, Virginia and showed positive results, reducing annual unplanned losses from 22 to 2 by 2016, when the program was expanded to provide greater mental health support to the larger submarine force.
The Navy also set up eMHP services for Marines and the special operations forces as well.
The Chinese People's Liberation Army Navy, according to the latest Department of Defense assessment of the Chinese military, is the largest naval force in the world, but its capabilities still trail behind those of the US Navy.
The overall quality of the Chinese navy is improving though as China builds new classes of ships and submarines and pushes forward with efforts to build a world-class fighting force by the middle of this century.
Read the original article on Business Insider