In Reply: Dr Finucane rightly questions the relationship between hyperglycemia and the development of diabetic polyneuropathy in patients with type 2 diabetes and whether tight control is truly effective. The 3 RCTs he cites did not show a reduction in the prevalence of the disorder in those whose serum glucose was tightly controlled.
One of the major obstacles in addressing this question is establishing a diagnosis of polyneuropathy (and diabetic polyneuropathy in particular). An expert consensus report1 on the definition of polyneuropathy underscored the difficulty of deciding what actually constitutes a polyneuropathy. But the authors of that report did stress the importance of including several criteria, including nerve conduction studies and possibly epidermal nerve fiber counts, as part of that definition.
Rutkove SB. Diabetic Polyneuropathy and Glucose Control—Reply. JAMA. 2010;303(5):420-421. doi:10.1001/jama.2010.56