Clinical outcomes and prognostic factors in patients with spinal dural arteriovenous fistula: a nearly 10-year prospective cohort study

OBJECTIVE: This prospective cohort study aimed to evaluate the long-term outcomes of patients with spinal dural arteriovenous fistulas (SDAVFs) nearly 10 years after treatment and identify prognostic factors influencing recovery and progression. METHODS: Seventy-six patients diagnosed with SDAVF from two centers in China were treated with microsurgery, endovascular therapy, or combined therapy based on angiographic findings. Baseline data collected included age, gender, disease duration, modified Aminoff-Logue Scale (mALS) scores, the presence of numbness and pain (modified Denis Scale [mDS] scores), fistula location, and treatment method. Follow-up evaluations were conducted at 3 months, 6 months, 1 year, 6 years, and nearly 10 years after treatment, in which mALS and mDS scores were recorded. RESULTS: The mean follow-up duration was 121.6 (SD 3.8) months. Fistulas were predominantly in the lower thoracic spine (T7-12, 48.7%), and 82.9% of the patients were male. Improvement was observed in 63.2% of the patients, whereas 55.3% had poor outcomes (mALS score ≥ 4) and 32.9% showed late clinical deterioration. Patient age > 55 years (OR 4.316, 95% CI 1.312-14.196; p = 0.016) and pretreatment disability (moderate: OR 10.160, 95% CI 1.932-53.433, p = 0.006; severe: OR 22.112, 95% CI 2.440-200.344, p = 0.006) were predictors of poor 10-year outcomes. Pretreatment disability (moderate: OR 8.432, 95% CI 1.008-70.512, p = 0.049; severe: OR 12.838, 95% CI 1.231-133.907, p = 0.033) were further associated with late clinical deterioration. CONCLUSIONS: Patients with SDAVFs show early functional improvement but progressive decline over time. Older age and moderate to severe pretreatment disability predicted poor outcomes, while moderate to severe pretreatment disability was associated with late clinical deterioration. These findings highlight the need for early intervention and long-term rehabilitation to mitigate functional decline.