Study Suggests Diffusion of New Drug Therapy for PTSD Lessens with Distance
With the growing emphasis on the delivery of evidence-based medicine, there has been increasing interest in identifying processes that facilitate the diffusion and dissemination of newly developed treatments from research into routine clinical practice. This study sought to evaluate the pace and reach of the passive dissemination of a novel, but as yet un-established treatment with the drug prazosin for post-traumatic stress disorder (PTSD) within the VA health care system. Prazosin has been used for many years in the treatment of hypertension, and several years ago researchers at the VA Puget Sound Healthcare System published an article on its effectiveness in treating nightmares and hyper-arousal associated with chronic PTSD. Investigators in this study used geographic surveillance data to track the diffusion of prazosin to treat Veterans diagnosed with PTSD in the VA Puget Sound Healthcare System, and at VAMCs located in four distance-defined groups ranging up to 2500 miles or farther from Puget Sound. Investigators also compared Veterans treated in mental health specialty programs with those treated exclusively in VA primary care or medical or surgical program locations. Veterans in this study cohort were diagnosed with PTSD in FY04 (n=203,414) and FY06 (n=319,670), and data were analyzed to show changes in the use of prazosin during this two-year period.
Findings show that the passive diffusion of a new treatment can be rapid in the immediate area in which it is developed, but the geographic gradient of use seems to be steep and changed little during a two-year period, even when cost and organizational barriers were minimal. Veterans with PTSD treated in the area nearest to Puget Sound (<499 miles) were about 63% less likely in 2004 and about 49% less likely in 2006 to be prescribed prazosin than their counterparts treated within Puget Sound. Moreover, whereas 37.6% of Veterans within Puget Sound were prescribed prazosin in 2004, only 18.2% were treated with prazosin at VA medical centers up to 499 miles away, 6.7% at centers 500 to 999 miles away, 4.0% at centers 1000 to 2499 miles away, and just 1.9% at centers 2500 miles away or farther. Most Veterans who were prescribed prazosin were treated in a mental health specialty clinic (92.9% in '04 and 86.7% in '06). These results suggest that if and when new treatments are definitively demonstrated to be effective, more active dissemination is likely to be needed, especially in geographically remote areas.
Harpaz-Rotem I, Rosenheck R. Tracing the flow of knowledge: Geographic variability in the diffusion of prazosin use for the treatment of post-traumatic stress disorder nationally in the Department of Veterans Affairs. Archives of General Psychiatry April 2009;66(4):417-421.
Both authors are part of the VA Connecticut Healthcare System.