Assessment of plasma C-reactive protein as a biomarker of posttraumatic stress disorder risk

TY - JOUR

T1 - Assessment of plasma C-reactive protein as a biomarker of posttraumatic stress disorder risk

AU - Eraly, Satish A

AU - Nievergelt, Caroline M

AU - Maihofer, Adam X

AU - Barkauskas, Donald A

AU - Biswas, Nilima

AU - Agorastos, Agorastos

AU - O'Connor, Daniel T

AU - Baker, Dewleen G

AU - Marine Resiliency Study Team

PY - 2014/4/1

Y1 - 2014/4/1

N2 - IMPORTANCE: Posttraumatic stress disorder (PTSD) has been associated in cross-sectional studies with peripheral inflammation. It is not known whether this observed association is the result of PTSD predisposing to inflammation (as sometimes postulated) or to inflammation predisposing to PTSD.OBJECTIVE: To determine whether plasma concentration of the inflammatory marker C-reactive protein (CRP) helps predict PTSD symptoms.DESIGN, SETTING, AND PARTICIPANTS: The Marine Resiliency Study, a prospective study of approximately 2600 war zone-deployed Marines, evaluated PTSD symptoms and various physiological and psychological parameters before deployment and at approximately 3 and 6 months following a 7-month deployment. Participants were recruited from 4 all-male infantry battalions imminently deploying to a war zone. Participation was requested of 2978 individuals; 2610 people (87.6%) consented and 2555 (85.8%) were included in the present analysis. Postdeployment data on combat-related trauma were included for 2208 participants (86.4% of the 2555 included) and on PTSD symptoms at 3 and 6 months after deployment for 1861 (72.8%) and 1617 (63.3%) participants, respectively.MAIN OUTCOMES AND MEASURES: Severity of PTSD symptoms 3 months after deployment assessed by the Clinician-Administered PTSD Scale (CAPS).RESULTS: We determined the effects of baseline plasma CRP concentration on postdeployment CAPS using zero-inflated negative binomial regression (ZINBR), a procedure designed for distributions, such as CAPS in this study, that have an excess of zeroes in addition to being positively skewed. Adjusting for the baseline CAPS score, trauma exposure, and other relevant covariates, we found baseline plasma CRP concentration to be a highly significant overall predictor of postdeployment CAPS scores (P = .002): each 10-fold increment in CRP concentration was associated with an odds ratio of nonzero outcome (presence vs absence of any PTSD symptoms) of 1.51 (95% CI, 1.15-1.97; P = .003) and a fold increase in outcome with a nonzero value (extent of symptoms when present) of 1.06 (95% CI, 0.99-1.14; P = .09).CONCLUSIONS: AND RELEVANCE A marker of peripheral inflammation, plasma CRP may be prospectively associated with PTSD symptom emergence, suggesting that inflammation may predispose to PTSD.

AB - IMPORTANCE: Posttraumatic stress disorder (PTSD) has been associated in cross-sectional studies with peripheral inflammation. It is not known whether this observed association is the result of PTSD predisposing to inflammation (as sometimes postulated) or to inflammation predisposing to PTSD.OBJECTIVE: To determine whether plasma concentration of the inflammatory marker C-reactive protein (CRP) helps predict PTSD symptoms.DESIGN, SETTING, AND PARTICIPANTS: The Marine Resiliency Study, a prospective study of approximately 2600 war zone-deployed Marines, evaluated PTSD symptoms and various physiological and psychological parameters before deployment and at approximately 3 and 6 months following a 7-month deployment. Participants were recruited from 4 all-male infantry battalions imminently deploying to a war zone. Participation was requested of 2978 individuals; 2610 people (87.6%) consented and 2555 (85.8%) were included in the present analysis. Postdeployment data on combat-related trauma were included for 2208 participants (86.4% of the 2555 included) and on PTSD symptoms at 3 and 6 months after deployment for 1861 (72.8%) and 1617 (63.3%) participants, respectively.MAIN OUTCOMES AND MEASURES: Severity of PTSD symptoms 3 months after deployment assessed by the Clinician-Administered PTSD Scale (CAPS).RESULTS: We determined the effects of baseline plasma CRP concentration on postdeployment CAPS using zero-inflated negative binomial regression (ZINBR), a procedure designed for distributions, such as CAPS in this study, that have an excess of zeroes in addition to being positively skewed. Adjusting for the baseline CAPS score, trauma exposure, and other relevant covariates, we found baseline plasma CRP concentration to be a highly significant overall predictor of postdeployment CAPS scores (P = .002): each 10-fold increment in CRP concentration was associated with an odds ratio of nonzero outcome (presence vs absence of any PTSD symptoms) of 1.51 (95% CI, 1.15-1.97; P = .003) and a fold increase in outcome with a nonzero value (extent of symptoms when present) of 1.06 (95% CI, 0.99-1.14; P = .09).CONCLUSIONS: AND RELEVANCE A marker of peripheral inflammation, plasma CRP may be prospectively associated with PTSD symptom emergence, suggesting that inflammation may predispose to PTSD.

KW - Adult

KW - Biological Markers

KW - C-Reactive Protein

KW - Combat Disorders

KW - Humans

KW - Inflammation

KW - Longitudinal Studies

KW - Male

KW - Military Personnel

KW - Neuropsychological Tests

KW - Predictive Value of Tests

KW - Prospective Studies

KW - Resilience, Psychological

KW - Risk Assessment

KW - Stress Disorders, Post-Traumatic

U2 - 10.1001/jamapsychiatry.2013.4374

DO - 10.1001/jamapsychiatry.2013.4374

M3 - SCORING: Journal article

C2 - 24576974

VL - 71

SP - 423

EP - 431

JO - JAMA PSYCHIAT

JF - JAMA PSYCHIAT

SN - 2168-622X

IS - 4

ER -