IFNG and diabetic autonomic neuropathy: Cardiac autonomic reactivity tests: reflex response of HR to FTB (p = 0.076), an important early indicator of diabetic autonomic neuropathy, HR response to Valsalva maneuver (p = 0.399) and BP response to IHG test (p = 0.819) did not differ significantly but HR response to OST assessed by 30∶15 ratio (p = 0.036) differed significantly between IFG and NFG group (Table 3).