Clinical Summary
Clinical Summary: Association of Intrusive Posttraumatic Stress Symptoms With Elevated C-Reactive Protein Levels in World Trade Center Responders
Patients with posttraumatic stress disorder often carry a substantial burden of cardiovascular and metabolic risk, and inflammation may be one pathway linking these problems. In World Trade Center responders, this study asks a clinically practical question: which PTSD symptoms track most closely with elevated C-reactive protein after accounting for obesity, lipid levels, and medical comorbidity?
Design
multivariable binary logistic regression analysis with Forward Wald estimation
N
371 (78.8%) met eligibility criteria and completed the study
Population
WTC rescue, recovery, and clean-up workers (“responders”)
Duration
conducted between April 2013 and September 2017
Key Findings
- In the multivariable model, obesity was independently associated with CRP >3 mg/dL (odds ratio [OR]=2.96; 95% CI [1.68, 5.21]; Wald χ2 =14.04; p<.001).
- Greater severity of re-experiencing/intrusion symptoms was independently associated with CRP >3 mg/dL (OR=1.38; 95% CI [1.08, 1.75]; Wald χ2 =6.82; p=.009).
- Lower HDL cholesterol levels were independently associated with CRP >3 mg/dL (OR=0.97; 95% CI [0.95, 0.99]; Wald χ2 =5.82; p=.016).
- In planned post-hoc analyses of individual intrusion symptoms, greater emotional reactivity to trauma cues was independently associated with CRP >3 mg/dL (OR= 1.50; 95% CI [1.15, 1.96]; Wald χ2 =8.80; p=.003), while no other symptoms were significant (all Wald χ2 .52).
- For each SD unit increase in re-experiencing/intrusion symptom severity (approximately 10.9 points), the odds of having elevated CRP increased by 38%.
Clinical Bottom Line
In World Trade Center responders, elevated CRP tracked not only with obesity and lower HDL cholesterol but also with more severe PTSD intrusion symptoms, especially emotional reactivity to trauma cues. PTSD-related inflammation should not be assumed to be explained by medical comorbidity alone.
Practice Implications
- When evaluating posttraumatic stress disorder in trauma-exposed patients, assess intrusion symptoms closely, particularly emotional reactivity to trauma cues, because this symptom was independently linked to CRP >3 mg/dL (OR= 1.50; 95% CI [1.15, 1.96]; p=.003).
- Include metabolic screening in patients with posttraumatic stress disorder, since obesity (OR=2.96; 95% CI [1.68, 5.21]; p<.001) and lower HDL cholesterol (OR=0.97; 95% CI [0.95, 0.99]; p=.016) were independently associated with elevated CRP.
- Interpret an elevated CRP >3 mg/dL in the context of both psychiatric and metabolic risk, as the study used this cutoff based on clinically significant inflammation in populations with PTSD and guidelines for increased cardiovascular disease risk.
- Consider integrated treatment planning that addresses both posttraumatic stress disorder symptoms and metabolic risk factors such as obesity and dyslipidemia, consistent with the pattern of independent correlates identified in the final model.
