* Study of psychological impact of Iraq, Afghan conflicts
* Results compared to studies on U.S. troops' mental health
* "Considerable efforts" in UK to offer psychological help
By Kate Kelland
LONDON, Feb 27 (Reuters) - Intervention strategies have helped mitigate the psychological impact on British soldiers of more than 10 years of conflict in Iraq and Afghanistan, a new study suggests, leaving them mentally healthier than their U.S. peers.
But the study, by the King's Centre for Military Health Research at King's College London, found some British soldiers - particularly reservists and soldiers deployed in combat - do seem more vulnerable to mental illness when they come home.
It also found alcohol abuse and violence remain "areas of concern".
"Overall, UK military personnel have remained relatively resilient in spite of the stresses endured in Iraq and Afghanistan," said Deirdre MacManus, who led the study.
She said Britain's armed forces have made "considerable efforts" to improve deployed solders' access to high-quality mental health services and introduce interventions aimed at reducing the psychological impact of conflict.
MacManus' team conducted a so-called meta-analysis that reviewed 34 published studies - some going back 15 years - of the psychological impact on British soldiers of deployments to Iraq and Afghanistan. Where possible, they compared findings to those of mental health studies of U.S. military personnel.
The results were published on Thursday in the Journal of the Royal Army Medical Corps, a specialist journal in the British Medical Journal (BMJ) group.
They found rates of post-traumatic stress disorder (PTSD) among British regular troops range from 1.30 to 4.8 percent - similar to the 3 percent rate in the general population.
Rates of common mental disorders such as anxiety and depression among soldiers ranged from 16.7 to 19.6 percent - also similar to the general population.
But PTSD rates among troops involved in direct combat are higher, at around 7.0 percent. And reservists were also more than twice as likely to report common mental illnesses and PTSD if they had been in Iraq or Afghanistan than if they had not.
PTSD rates are significantly lower for British troops than their U.S. peers, the researchers said, citing recent studies showing U.S. military PTSD rates of 21 to 29 percent.
They noted that American soldiers tend to be younger, from lower socio-economic background and undertake longer tours of duty - of 12 months compared with six months for British troops.
"(And) there appears to be some evidence that the considerable efforts the UK Armed Forces have made to ensure that deployed personnel are well trained, well led, cohesive, have access to high quality mental health services and a number of evidence based mitigation measures ... are important," the researchers wrote.
Mild traumatic brain injury (mTBI) is also relatively uncommon among British troops, at around 4.4 percent for regular troops and 9.5 percent for those in combat roles.
This contrasts again with the United States, where mTBI has been described as a "signature injury" affecting 12 to 23 percent of deployed troops.
The researchers warned, however, that harmful drinking is a cause for concern among British troops, affecting up to one in five regular soldiers. Soldiers returning from deployment are also more likely to be aggressive and violent, the study found, particularly combat troops with mental health problems. (Reporting by Kate Kelland, editing by Larry King)