The startling figures are contained in an analysis by the Canadian Forces Health Services Branch, which reviewed the medical files of over 30,000 troops who deployed as part of the nearly 12 year Afghan campaign.
The analysis focuses on the long-term career impact of service-related mental disorders and how they are impacted by the military's universality of service rule, which requires all members to be fit to deploy both at home and overseas.
In the fall of 2013, a number of soldiers, many with post-traumatic stress, came forward to say they were being declared unfit and hustled out of uniform.
The analysis, by Mark Zamorski and David Boulos, finds that five years after the first deployment, 40 per cent of soldiers with a mental-health diagnosis were likely to have developed career limitations that would lead to being released, compared with 11 per cent with no medical condition.
After 10 years, the figures jump to 68.8 per cent and 19.8 per cent respectively.
National Defence has invested a lot of time and effort to convince soldiers suffering with mental illness to seek help, but a major barrier in the "self identification" campaign has been the worry that once they seek help, their careers are over.
Former veterans ombudsman Pat Stogran said it is a real fear and the new research will come as little comfort.
"The soldiers call it going away to the island of broken toys," Stogran said. "It's a career death sentence and they're not coming back."
Being diagnosed with a career-limiting condition — mental or physical — does not mean an automatic medical release, but it does set the wheels in motion, said Zamorski.
Some people with either depression, post-traumatic stress or anxiety, which make up the bulk of the post-combat afflictions, respond well to treatment and can lead productive lives, said Zamorski.
But they still might not meet the service standard, he cautioned.
"A lot of people are found to be unfit for continued service, even though we know many of them are just great," Zamorski said. "These are people, many of whom we known from our clinicians, are great. Yes, they have PTSD — or they had PTSD and they no longer meet the criteria for the condition. Maybe they have to take medication and they would be fit for just about any other job under the sun, but not for military service."
Stogran said he believes the universality standard needs to be reviewed and pointed to the fact that overweight — or physically unfit — members can obtain a doctor's exemption.
"I could take you on a walk through (National Defence Headquarters) and show you all the plugs in uniform who couldn't do the PT test," he said. "So they've really got to rethink this."
Prior to the Bosnia peacekeeping mission of the 1990s, Stogran said, the army made room for soldiers who may have been broken by past wars, giving them barracks tasks that were essential and but didn't involve operations.
"All that they want to do is still feel like they contribute to the team somehow," he said. "That by itself is very therapeutic."
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