--from being 'co-morbid'; that is having problems with the spine causing nerve compression that may be superimposed on other more peripheral pathologic processes going on.

There is even a category name for this--'double-crush hypothesis'--in which a nerve already compromised by some difficulty, such as glucose dysregulation, is then compressed somewhere along its pathway by mechanical forces and the symptoms thus produced are 'greater than the sum of the parts". This is often reported by diabetics who may have spinal problems, but it is likely present in those who have other causes of peripheral neuropathy (autoimmune, toxic) more often than it is generally looked for, especially when they may also have spinal issues.