Two clinical studies of University of Miami  has been published.  
Journal of Diabetes & Metabolic Disorders

“New method of sudomotor function measurement to detect microvascular disease and sweat gland nerve or unmyelinated C fiber dysfunction in adults with retinopathy.”

To read the full text, please, click on the link  :
https://link.springer.com/epdf/10.1186/s40200-017-0307-5?author_access_token=yMeShYektBqK04DCxQXpt2_BpE1tBhCbnbw3BuzI2RM4Z0uPyzMHGVmsNO7ZD7TLgsTexswgbl-9xBh4UB79QRgX4NG_4gANx60RVAF_B3itd8Pu7C3Vf-XOpaOj-PFGSfTragPcmqcuS-b-fhr59A==

Open Journal of Internal Medicine

“Relationship Between Vitamin D Status, Autonomic nervous system activity and Cardio-Metabolic Risk”

http://file.scirp.org/pdf/OJIM_2017080815310123.pdf