Prolonged deployments can cause mental problems, research suggests
Nearly 4,000 new cases of mental health disorder were diagnosed among armed services personnel last year, according to the Ministry of Defence (MoD).
Statistics showed there were 3,917 new cases of disorder in 2007, amounting to 4.5 per 1,000 forces members.
They also showed that personnel sent to Afghanistan or Iraq were more likely to suffer post traumatic stress disorder.
The MoD said the "vast majority" of those who came forward for treatment were able to return to service.
The latest statistics, relating to the final quarter of 2007, showed there were 195,100 serving personnel.
A breakdown revealed no significant differences in the rates of overall mental disorder between those deployed to Iraq or Afghanistan and those who were not.
Researchers said those undergoing prolonged periods of deployment are more likely to drink too much and suffer stress.
But the figures showed 38 people sent to these battle zones were diagnosed with post traumatic stress disorder, compared to five who were not deployed in either country.
Chris Williams, of the Defence Medical Services Department, said only about 150 people a year were discharged for mental health reasons.
"What that demonstrates is that people who come forward and get treatment, the vast majority of them go back to service," he said.
He added that the figures showing a higher rate of PTSD among those who served in Iraq and Afghanistan did not surprise him but added that "absolute numbers" were small.
The statistics cannot be compared to previous years because the MoD introduced new methods of collating figures for 2007.
In its report, DASA said the figures "did not cover the full picture of all mental disorders in the UK Armed Forces".
It said some personnel may have refused - or not required - referral to community mental health services.
"It is also possible that the support through a strong culture of comradeship within the Armed Forces may have served to minimise the number and severity of symptoms experienced by some cases," it added.
Women had a statistically significant higher rate of mental disorder assessment at 8.2 per 1,000, double that of male personnel at four per 1,000.
Surgeon Commander Neil Greenberg, senior lecturer in military psychiatry who is on secondment to King's College, London, said the difference in disorder rates between men and women probably reflected those in society.
Researchers at King's College have previously said those undergoing prolonged periods of deployment are more likely to drink too much and suffer stress.
Last year, a sample of 5,547 personnel found evidence of mental health problems and greater strain on families if people were deployed for more than 13 months in total over a three-year period.