TY - JOUR AU - B. R. Vaughan AU - Y. Lu AU - N. E. Slama AU - M. B. Does AU - M. E. Hirschtritt AU - K. K. Ridout AU - M. T. Koshy AU - K. C. Young-Wolff A1 - AB - BACKGROUND: Posttraumatic stress disorder (PTSD) is often underdiagnosed based on medical records. This study aimed to estimate the prevalence and health care utilization of individuals with PTSD and other trauma-related disorders in a large, integrated health care system. METHODS: Adults (between the ages of 18 and 65) with Kaiser Permanente Northern California membership and ≥ 1 outpatient visit in 2022 were eligible. Unspecified/other specified trauma and stressor-related disorder, acute stress disorder, and PTSD were based on diagnosis codes from the International Classification of Diseases, 10th Revision, Clinical Modification. The Primary Care PTSD (PC-PTSD) Scale was used as a screening tool. Prevalence was assessed overall and among the subset of patients seen in primary care, psychiatry, and addiction medicine. To contextualize health care utilization, the authors compared patients with trauma-related disorders to those with major depressive disorder. RESULTS: Of the 2,128,670 eligible adults, the overall prevalence of trauma-related diagnoses and positive screening on PC-PTSD was 4.9% (103,947); 1.3% (n = 27,670) had PTSD, 1.9% (n = 41,205) had unspecified/other specified trauma and stressor-related disorder, 0.1% (n = 1818) had acute stress disorder, and 1.6% (n = 33,254) screened positive on PC-PTSD without a trauma-related International Classification of Diseases code. Prevalence of trauma-related diagnoses by department was 18.3% (n = 47,516) in psychiatry, 16.5% (n = 3816) in addiction medicine, and 3.4% (n = 67,469) in primary care. There were no clinically meaningful differences in health care utilization between those with trauma-related diagnoses compared with major depressive disorder. CONCLUSION: Broadly defining trauma-related disorders and substantial symptoms may provide a more accurate representation of the actual prevalence of PTSD in a health care system. These data may help health care leaders plan treatment options for this diverse group of individuals. AD - Addiction Medicine Recovery Services, Kaiser Permanente, Walnut Creek, CA, USA.; Division of Research, Kaiser Permanente Northern California, Pleasanton, CA, USA.; Department of Psychiatry, Kaiser Permanente, Oakland Medical Center, Oakland, CA, USA.; Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, CA, USA.; Department of Psychiatry, Kaiser Permanente, Santa Rosa Medical Center, Santa Rosa, CA, USA.; Permanente Medical Group, Kaiser Permanente Northern California, Oakland, CA, USA. AN - 40403032 BT - Perm J C5 - Healthcare Disparities; Medically Unexplained Symptoms DA - May 22 DO - 10.7812/tpp/24.191 DP - NLM ET - 20250522 JF - Perm J LA - eng N2 - BACKGROUND: Posttraumatic stress disorder (PTSD) is often underdiagnosed based on medical records. This study aimed to estimate the prevalence and health care utilization of individuals with PTSD and other trauma-related disorders in a large, integrated health care system. METHODS: Adults (between the ages of 18 and 65) with Kaiser Permanente Northern California membership and ≥ 1 outpatient visit in 2022 were eligible. Unspecified/other specified trauma and stressor-related disorder, acute stress disorder, and PTSD were based on diagnosis codes from the International Classification of Diseases, 10th Revision, Clinical Modification. The Primary Care PTSD (PC-PTSD) Scale was used as a screening tool. Prevalence was assessed overall and among the subset of patients seen in primary care, psychiatry, and addiction medicine. To contextualize health care utilization, the authors compared patients with trauma-related disorders to those with major depressive disorder. RESULTS: Of the 2,128,670 eligible adults, the overall prevalence of trauma-related diagnoses and positive screening on PC-PTSD was 4.9% (103,947); 1.3% (n = 27,670) had PTSD, 1.9% (n = 41,205) had unspecified/other specified trauma and stressor-related disorder, 0.1% (n = 1818) had acute stress disorder, and 1.6% (n = 33,254) screened positive on PC-PTSD without a trauma-related International Classification of Diseases code. Prevalence of trauma-related diagnoses by department was 18.3% (n = 47,516) in psychiatry, 16.5% (n = 3816) in addiction medicine, and 3.4% (n = 67,469) in primary care. There were no clinically meaningful differences in health care utilization between those with trauma-related diagnoses compared with major depressive disorder. CONCLUSION: Broadly defining trauma-related disorders and substantial symptoms may provide a more accurate representation of the actual prevalence of PTSD in a health care system. These data may help health care leaders plan treatment options for this diverse group of individuals. PY - 2025 SN - 1552-5767 SP - 1 EP - 9+ ST - Prevalence and Health Care Utilization of Posttraumatic Stress Disorder and Other Trauma-Related Mental Health Diagnoses in a Large, Integrated Health Care System T1 - Prevalence and Health Care Utilization of Posttraumatic Stress Disorder and Other Trauma-Related Mental Health Diagnoses in a Large, Integrated Health Care System T2 - Perm J TI - Prevalence and Health Care Utilization of Posttraumatic Stress Disorder and Other Trauma-Related Mental Health Diagnoses in a Large, Integrated Health Care System U1 - Healthcare Disparities; Medically Unexplained Symptoms U3 - 10.7812/tpp/24.191 VO - 1552-5767 Y1 - 2025 ER -