Elevated homocysteine (Hcy) levels are predictors of cardiovascular disease (CVD). Hyperhomocysteinemia
has also been associated with total and CVD mortality. However, whether Hcy is just a marker or plays
a causal role in CVD remains to be elucidated. In this narrative review, we discuss the associations between Hcy
and non-cardiac vascular diseases, namely stroke, peripheral artery disease (PAD), carotid artery disease, chronic
kidney disease (CKD), atherosclerotic renal artery stenosis (ARAS), abdominal aortic aneurysm (AAA) and
erectile dysfunction (ED). The effects of several drugs on Hcy levels are also considered.
Folic acid, vitamin B6 and B12 supplementation can significantly decrease circulating Hcy concentrations but
their effects on CVD risk reduction are conflicting. No current guidelines recommend the routine screening of
Hcy levels in patients with non-cardiac vascular diseases. Therefore, further research is needed to elucidate the
use of Hcy in the clinical practice.