- Patients with PTSD and no back pain at baseline were significantly more likely to have developed chronic back pain (CBP) at a 5-year follow-up than those without PTSD, independent of genetic and familiar factors.
Why this matters
- This study, involving participants of the Vietnam-Era Twin Registry, is the first longitudinal co-twin control study of identical twins to find a significant association between a psychological risk factor and incident back pain.
- 171 monozygotic twin pairs from the Vietnam-Era Twin Registry completed the PTSD Symptom Checklist and a self-report measure of CBP at baseline.
- 227 men including 91 twin pairs completed a follow-up survey at 5 years.
- Primary outcome: incident CBP at 5 years.
- Funding: None disclosed.
- At 5-year follow-up, 110 men reported incident CBP.
- Both co-twins reported on the presence or absence of incident CBP at follow-up in 86 twin pairs.
- 5-year CBP incidence was 64% in those with baseline PTSD symptoms and 41% in those without baseline PTSD symptoms.
- After adjusting for familial factors, baseline PTSD symptoms showed significant association with incident CBP at 5-year follow-up (risk ratio, 1.6; P=.001).
- Recall bias.
Coauthored with Antara Ghosh, PhD