CONCLUSIONS
In this study from a tertiary referral hospital and a population-based
cohort, we found no difference in vitamin B12 or folate deficiency, or
their serum levels between adult patients with VVS and controls;
nevertheless, frequent VVS was associated with a lower serum vitamin B12
compared to infrequent VVS. Future studies are warranted to investigate
the role of vitamin B12 deficiency in frequent VVS and the efficacy of
supplementation with vitamin B12 in these patients.