this is Marie- Today on Medscape Neurology there is an article about low vitamin D levels and how this influences development of carotid plaque (Atherosclerosis).

While this isn't the same as stenosis in veins, do note that they are not sure exactly how low vitamin D plays a role in this vascular process and suggest more study is needed.

See the paper here- http://stroke.ahajournals.org/content/42/8/2240




Vitamin D Deficiency Is Associated With Subclinical Carotid Atherosclerosis
stroke.ahajournals.org
Background and Purpose—The purpose of this study was to assess the association of vitamin D deficiency and indices of mineral metabolism with subclinical carotid markers that predict cardiovascular events.