Risk factors and co-morbidities in adolescent thromboembolism are different than those in younger children.

Introduction: In adolescent thromboembolism (TE), multiple risk factors (RFs) and co-morbidities (CMs) are reported, though overall prevalence has not been evaluated. We hypothesized that the spectrum of RFs/CMs in adolescent TE differs from children overall and sought to review Texas Children's Hospital's experience.

Patients/methods: Medical records of adolescents aged 12-21years, diagnosed with arterial or venous TE (AT/DVT) from 2004 to 2014, were retrospectively reviewed and analyzed with IRB approval.

Results: Sixty-four adolescents (median age 16, range 12-20years) met study criteria. Fifty-seven (89%) had DVT and six (9%) had AT. Associated RFs/CMs included obesity (47%), CVC (27%), infection (27%), surgery (27%), autoimmune disease (19%), immobility (22%), anatomical abnormality (20%), cancer (8%), estrogen therapy (6%), tobacco use (6%), trauma (3%), inherited thrombophilia (19%), and other medical conditions (11%). Fifty-two (81%) had ≥2 RFs/CMs. Therapy included anticoagulants, antiplatelet agents, and interventional therapy. Of those with follow-up imaging, 49 had complete or partial resolution, 5 had no change and 4 had progression. Fourteen (22%) had recurrent TE. The majority with recurrent TE (79%) had ≥2 RFs at initial diagnosis. Mean time to recurrence was 4.80years; time to recurrence was shorter for occlusive TE (p=0.026).

Conclusion: Adolescent TE is often multi-factorial with the majority having ≥2 RFs at diagnosis, suggesting the need for detailed evaluation for RFs in this population, which may enable optimal management including thromboprophylaxis, and institution of RF-modifying strategies to prevent occurrence/recurrence.