Staff Perspective: PTSD Incidence in the U.S. Military
Co-written by Larissa L. Tate
A quick search of the PTSD literature will show you widespread rates of PTSD in the U.S. military. In some studies, the rate is as low as 1.4% (Bliese, Wright, Adler, Thomas, & Hoge, 2007), and in others it is as high as 41.3% (Maguen, Lau, Madden, & Seal, 2012). There are a number of reasons for these highly discrepant rates, many of which are methodological differences. First, the rates may vary based on the sample selected. Studies that focus on deployments to Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) tend to have higher rates compared to pre-deployment rates (Kok, Herrell, Thomas, & Hoge, 2012). Other studies may limit their samples only to patients who are seeking treatment (Ramchand et al., 2010). Additionally, many studies utilize a cross-sectional design (Ramchand, Rudavsky, Grant, Tanielian, & Jaycox, 2015), which may miss Service members who experience PTSD at other timepoints post-deployment (Bliese et al., 2007; Hoge et al., 2004). Finally, rates may vary by the screening instrument utilized (Ramchand et al., 2010). As many clinicians can attest, patients may not screen positive for PTSD on all diagnostic measures due to differences in the measures.
With all of these methodological hurdles ahead of us, how can we know the true rate of PTSD in the U.S. military? To take on this challenge, researchers at CDP partnered with the Comparative Effectiveness and Provider-Induced Demand Collaboration (EPIC) Group at the Uniformed Services University of the Health Sciences to analyze military healthcare records in the Military Healthcare System (MHS). This approach allowed us to side step some of the hurdles previous studies have encountered so that we could get the most accurate rate of PTSD diagnosis in the military.
But before we get into what this study found, it is important we first discuss the differences in this data compared to the previous studies mentioned above. The previous studies aimed to identify the prevalence of PTSD, or the percentage of the population with PTSD. The present research identified the incidence of PTSD, or the rate of new PTSD diagnoses, in the MHS. This allows us to measure cases as they are diagnosed rather than relying on a specific time period post-deployment.
Now for the findings: between 2007 and 2015 diagnostic rates were lowest in 2007 with an incidence rate of 6.74 per 1,000-person-years. After peaking in 2012 at a rate of 9.69 per 1,000-person-years, the rate gradually declined to a rate of 8.37 per 1,000-person-years at the end of the study period in 2015.
We also examined rates across demographics and military characteristics:
Age: Older service members (aged 40 and above) had the highest rates of PTSD. The lowest rates were in service members less than 20 years of age.
Sex: From 2007 to 2009, men had higher rates than women. However, in 2010, women exceeded men, which continued through the end of the study period in 2015.
Race: In White Service members, the rates of PTSD were fairly consistent from 2009 to 2012 when it began to decrease. However, the rates for Black Service members generally increased over the study period.
Marital Status: Contrary to what we typically see in behavioral health research, marital status was not protective against PTSD. Divorced Service members had the highest rates followed by married Service members, with both increasing over the study period. Single Service members, however, had much lower rates, which decreased over the study period. It is possible these higher rates are because their spouses encouraged them to seek care, resulting in a higher rate of diagnosis.
Service Branch: PTSD rates were highest in the Army. The Marine Corps also had an elevated rate of PTSD. The Navy, Air Force, and Coast Guard had comparatively lower rates throughout the study period.
Component: Active duty Service members had higher rates of PTSD compared to the Reserve and National Guard components. This difference may be in part because active duty Service members are more likely to receive care in the MHS than Reserve and National Guard Service members.
Rank/Grade: Junior Enlisted personnel had the highest rates of PTSD from 2008 to 2015. Senior Enlisted had the next highest rates. All officers (i.e., Junior, Senior, and Warrant) had lower rates comparatively.
As with any methodology, there are inherent weaknesses. These data only reflect the rates of PTSD diagnoses received within the MHS. Additionally, because this study examined medical codes, this does not reflect PTSD severity or type of index trauma. Finally, we do not know the diagnostic methods used by the provider.
To our knowledge, these numbers best represent the rates of PTSD in the U.S. military. These results may provide evidence of subgroups at greater risk of developing PTSD, which would allow the DoD to more effectively target these groups for prevention, assessment, and treatment.
The opinions in CDP Staff Perspective blogs are solely those of the author and do not necessarily reflect the opinion of the Uniformed Services University of the Health Science or the Department of Defense.
References
Bliese, P. D., Wright, K. M., Adler, A. B., Thomas, J. L., & Hoge, C. W. (2007). Timing of Postcombat Mental Health Assessments. https://doi.org/10.1037/1541-1559.4.3.141
Kok, B. C., Herrell, R. K., Thomas, J. L., & Hoge, C. W. (2012). Posttraumatic Stress Disorder Associated With Combat Service in Iraq or Afghanistan. The Journal of Nervous and Mental Disease, 200(5), 444–450. https://doi.org/10.1097/NMD.0b013e3182532312
Maguen, S., Ren, L., Bosch, J. O., Marmar, C. R., & Seal, K. H. (2010). Gender differences in mental health diagnoses among Iraq and Afghanistan veterans enrolled in veterans affairs health care. American Journal of Public Health, 100(12), 2450–2456. https://doi.org/10.2105/AJPH.2009.166165
Ramchand, R., Rudavsky, R., Grant, S., Tanielian, T., & Jaycox, L. (2015). Prevalence of, Risk Factors for, and Consequences of Posttraumatic Stress Disorder and Other Mental Health Problems in Military Populations Deployed to Iraq and Afghanistan. Current Psychiatry Reports, 17(5), 37. https://doi.org/10.1007/s11920-015-0575-z
Ramchand, R., Schell, T. L., Karney, B. R., Osilla, K. C., Burns, R. M., & Caldarone, L. B. (2010). Disparate prevalence estimates of PTSD among service members who served in Iraq and Afghanistan: Possible explanations. Journal of Traumatic Stress, 23(1), n/a-n/a. https://doi.org/10.1002/jts.20486
Co-written by Larissa L. Tate
A quick search of the PTSD literature will show you widespread rates of PTSD in the U.S. military. In some studies, the rate is as low as 1.4% (Bliese, Wright, Adler, Thomas, & Hoge, 2007), and in others it is as high as 41.3% (Maguen, Lau, Madden, & Seal, 2012). There are a number of reasons for these highly discrepant rates, many of which are methodological differences. First, the rates may vary based on the sample selected. Studies that focus on deployments to Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) tend to have higher rates compared to pre-deployment rates (Kok, Herrell, Thomas, & Hoge, 2012). Other studies may limit their samples only to patients who are seeking treatment (Ramchand et al., 2010). Additionally, many studies utilize a cross-sectional design (Ramchand, Rudavsky, Grant, Tanielian, & Jaycox, 2015), which may miss Service members who experience PTSD at other timepoints post-deployment (Bliese et al., 2007; Hoge et al., 2004). Finally, rates may vary by the screening instrument utilized (Ramchand et al., 2010). As many clinicians can attest, patients may not screen positive for PTSD on all diagnostic measures due to differences in the measures.
With all of these methodological hurdles ahead of us, how can we know the true rate of PTSD in the U.S. military? To take on this challenge, researchers at CDP partnered with the Comparative Effectiveness and Provider-Induced Demand Collaboration (EPIC) Group at the Uniformed Services University of the Health Sciences to analyze military healthcare records in the Military Healthcare System (MHS). This approach allowed us to side step some of the hurdles previous studies have encountered so that we could get the most accurate rate of PTSD diagnosis in the military.
But before we get into what this study found, it is important we first discuss the differences in this data compared to the previous studies mentioned above. The previous studies aimed to identify the prevalence of PTSD, or the percentage of the population with PTSD. The present research identified the incidence of PTSD, or the rate of new PTSD diagnoses, in the MHS. This allows us to measure cases as they are diagnosed rather than relying on a specific time period post-deployment.
Now for the findings: between 2007 and 2015 diagnostic rates were lowest in 2007 with an incidence rate of 6.74 per 1,000-person-years. After peaking in 2012 at a rate of 9.69 per 1,000-person-years, the rate gradually declined to a rate of 8.37 per 1,000-person-years at the end of the study period in 2015.
We also examined rates across demographics and military characteristics:
Age: Older service members (aged 40 and above) had the highest rates of PTSD. The lowest rates were in service members less than 20 years of age.
Sex: From 2007 to 2009, men had higher rates than women. However, in 2010, women exceeded men, which continued through the end of the study period in 2015.
Race: In White Service members, the rates of PTSD were fairly consistent from 2009 to 2012 when it began to decrease. However, the rates for Black Service members generally increased over the study period.
Marital Status: Contrary to what we typically see in behavioral health research, marital status was not protective against PTSD. Divorced Service members had the highest rates followed by married Service members, with both increasing over the study period. Single Service members, however, had much lower rates, which decreased over the study period. It is possible these higher rates are because their spouses encouraged them to seek care, resulting in a higher rate of diagnosis.
Service Branch: PTSD rates were highest in the Army. The Marine Corps also had an elevated rate of PTSD. The Navy, Air Force, and Coast Guard had comparatively lower rates throughout the study period.
Component: Active duty Service members had higher rates of PTSD compared to the Reserve and National Guard components. This difference may be in part because active duty Service members are more likely to receive care in the MHS than Reserve and National Guard Service members.
Rank/Grade: Junior Enlisted personnel had the highest rates of PTSD from 2008 to 2015. Senior Enlisted had the next highest rates. All officers (i.e., Junior, Senior, and Warrant) had lower rates comparatively.
As with any methodology, there are inherent weaknesses. These data only reflect the rates of PTSD diagnoses received within the MHS. Additionally, because this study examined medical codes, this does not reflect PTSD severity or type of index trauma. Finally, we do not know the diagnostic methods used by the provider.
To our knowledge, these numbers best represent the rates of PTSD in the U.S. military. These results may provide evidence of subgroups at greater risk of developing PTSD, which would allow the DoD to more effectively target these groups for prevention, assessment, and treatment.
The opinions in CDP Staff Perspective blogs are solely those of the author and do not necessarily reflect the opinion of the Uniformed Services University of the Health Science or the Department of Defense.
References
Bliese, P. D., Wright, K. M., Adler, A. B., Thomas, J. L., & Hoge, C. W. (2007). Timing of Postcombat Mental Health Assessments. https://doi.org/10.1037/1541-1559.4.3.141
Kok, B. C., Herrell, R. K., Thomas, J. L., & Hoge, C. W. (2012). Posttraumatic Stress Disorder Associated With Combat Service in Iraq or Afghanistan. The Journal of Nervous and Mental Disease, 200(5), 444–450. https://doi.org/10.1097/NMD.0b013e3182532312
Maguen, S., Ren, L., Bosch, J. O., Marmar, C. R., & Seal, K. H. (2010). Gender differences in mental health diagnoses among Iraq and Afghanistan veterans enrolled in veterans affairs health care. American Journal of Public Health, 100(12), 2450–2456. https://doi.org/10.2105/AJPH.2009.166165
Ramchand, R., Rudavsky, R., Grant, S., Tanielian, T., & Jaycox, L. (2015). Prevalence of, Risk Factors for, and Consequences of Posttraumatic Stress Disorder and Other Mental Health Problems in Military Populations Deployed to Iraq and Afghanistan. Current Psychiatry Reports, 17(5), 37. https://doi.org/10.1007/s11920-015-0575-z
Ramchand, R., Schell, T. L., Karney, B. R., Osilla, K. C., Burns, R. M., & Caldarone, L. B. (2010). Disparate prevalence estimates of PTSD among service members who served in Iraq and Afghanistan: Possible explanations. Journal of Traumatic Stress, 23(1), n/a-n/a. https://doi.org/10.1002/jts.20486