In contrast, pain showed the most improvement 3-6 months after acute hospitalization, and then leveled off after 1 year. The investigative team, led by Rollin M. Gallagher, MD, MPH, reported results during a poster session at the 29th Annual Meeting of the American Academy of Pain Medicine.
"Our research confirms that chronic daily pain, including neuropathic pain, continues to be a burden for limb-injured servicemen, that post-traumatic stress is a far more prominent feature of recovery than in other chronic pain populations, and that returning to meaningful role functioning in their lives is challenging for many," said Dr. Gallagher, deputy national program director for pain management in the Department of Veterans Affairs and clinical professor of psychiatry and anesthesiology at the University of Pennsylvania and the Philadelphia VA Medical Center.
The researchers said surprisingly few studies have examined short- and long-term pain-related and behavioral-health outcomes in returning military personnel with major limb trauma.
"The difficulty lies in developing an effective methodology that not only enables investigators to classify in detail the nature and severity of injuries and to characterize psychosocial and initial treatment variables, but that also enables investigators to evaluate the longitudinal outcomes of wounded warriors as they seek to recover in geographically dispersed localities," Dr. Gallagher said.
Using a longitudinal study design, researchers conducted phone interviews with 277 combat-injured military service personnel every 3 months for 2 years, beginning after their initial hospitalization for acute care. Participants had sustained major injuries to extremities and were recruited from major military hospitals, primarily by on-site research staff. Initial evaluation and follow-up interviews were conducted at the Philadelphia VA Medical Center, adapting the training and methodology of the Behavioral Health Laboratory for telephone evaluation.
The mean age of participants was 28 years old, 49.1% were married and 43.1% had some college education. Their injuries were as follows: 83.2% suffered lower extremity (LE) injury, 33.5% LE amputation, 8.9% bilateral LE amputation, 48.7% upper extremity (UE) injury and 8.9% UE amputation.
Respondents answered questions designed to measure multiple outcomes related to pain and behavioral health. Tools for measurement included the Brief Pain Inventory (BPI), Neuropathic Pain Scale (NPS), Treatment Outcomes in Pain Survey (TOPS) and VA Behavioral Health Laboratory. Institutional Review Boards from the Philadelphia VA, University of Pennsylvania, Walter Reed National Military Medical Center and Brooke Army Medical Center approved the study.
The BPI average and worst pain and the NPS items and subscales were significantly lower (P<0.05) post treatment compared with baseline with no significant statistical differences noted at time points beyond 6 months. Across various time points, 13.5% reported depression, 5% suicidal ideation and 13.9% generalized anxiety disorder. Nearly half of participants, 45.9%, reported a low level of PTSD, and an additional 11.7% reported a high level.
The results suggest that severely injured veterans will need ongoing biobehavioral pain and psychological care to help them cope with the pain and trauma of injury, Dr. Gallagher said. He called for a focus on occupational and vocational rehabilitation to help service members re-establish meaningful lives in their communities.
Whether early intervention with aggressive pain management, including continuous neural blockade, will ultimately change the trajectory of chronic pain following severe injury, remains to be seen, Dr. Gallagher said.
"Unlike animal models that demonstrate this construct, the course of recovery for injured warriors is fraught with physical, psychological and social uncertainty," he said. "Future analyses on a larger sample may reveal characteristics that predict better outcomes."
Poster 144 - A Longitudinal Investigation of Major Combat Limb Injuries: The Regional Analgesia Military Battlefield Pain Outcomes Study (RAMBPOS)
Funding: 1) VA Merit Award, Department of Rehabilitation Research and Development, 2007-2011 2) Henry M Jackson Foundation/Defense and Veterans Center for Integrative Pain Management, 2011-2013
The American Academy of Pain Medicine is the premiere 2,400-member medical association for pain physicians and their treatment teams. Now in its 30th year of service, the Academy's mission is to optimize the health of patients in pain and eliminate it as a major public health problem by advancing the practice and specialty of pain medicine through education, training, advocacy and research. Information is available on the Academy's website at painmed.org.