One of the studies identified three factors contributing to patients going abroad seeking treatment: a loss of faith in the Canadian health system when it did not provide access to CCSVI treatment in Canada, hope in the new treatment as a solution for their worsening health, and trust in the MS community and the organizations, clinics and doctors facilitating or providing the desired operation. Conversely, the other study concluded that sense of community and cooperation (from family, MS groups and the general population) was a key motivating factor. Other motivating factors included media reports, perception of approval from their health providers, the apparent low risk of the operation, or accessibility of the hospital that offered the procedure directly or through a medical tourism company. On the other hand, hesitating factors included the cost and effort required for the operation, the mistrust of foreign health systems, the underlying rationale for the operation, or advice against the procedure from trusted health providers.In 2013, a case-control study found evidence against the involvement of chronic cerebrospinal venous abnormalities in MS. Later in 2013 a study found that vein narrowing appears to be present equally in those with and without MS on ultrasound and catheter venography. The results of the study were described as a "death knell" for Zambonis theory. Another study released by the University of British Columbia in 2017 was described as a "definitive debunking" of liberation therapy.
These include risk factors such as Epstein-Barr infection, parental ancestry, date of birth and geographic location. MS is also more common in women, while venous diseases are more common in men. Venous pathology is commonly associated with hypertension, infarcts, edema and transient ischemia, and occurs more often with age, however these conditions are hardly ever seen in MS and the disease seldom appears after age 50. Finally, an organ-specific immune response is not seen in any other kind of venous disease. Iron deposits
Iron deposition as a cause of MS received support when a relationship between venous pressure and iron depositions in MS patients was found in a neuroimaging study, and criticism as other researchers found normal ferritin levels in the cerebrospinal fluid of MS patients. Additionally iron deposition occurs in different neurological diseases such as Alzheimers disease or Parkinsons disease that are not associated with CCSVI. Evidence linking CCSVI and iron deposition is lacking, and dysregulation of iron metabolism in MS is more complex than simply iron accumulation in the brain tissue. Genetics
A small genetic study looked at fifteen MS patients who also had CCSVI. It found 234 specific copy number variations in the human leukocyte antigen focus. Of these, GRB2, HSPA1L and HSPA1A were found to be specifically connected to both MS and angiogenesis, TAF11 was connected to both MS and artery passage, and HLA-DQA2 was suggestive of having an implication for angiogenesis as it interacts with CD4.