Skin temperature in the neuropathic diabetic foot

Several authors have reported higher skin temperature in the feet of diabet ic subjects with autonomic neuropathy. We reexamined this association in a cross-sectional study of 712 veterans with diabetes mellitus. Potential sub jects included all diabetic patients enrolled in a general internal medicin e clinic at a veterans affairs healthcare system. Sensory neuropathy was de fined as any pedal insensitivity to the 5.07 monofilament. Autonomic neurop athy was determined using standard cardiovascular reflex tests. An infrared surface scanner was used to measure foot skin temperature at multiple site s. Subjects with sensory neuropathy had lower mean plantar foot skill tempe rature than those without (28.4 degreesC vs. 28.9 degreesC, P=.0101). Auton omic neuropathy as a dichotomous variable was unrelated to foot skill tempe rature. Foot skill temperature, though, negatively correlated with greater drop in systolic blood pressure with standing, which is an indicator of aut onomic neuropathy (r=-.08, P=.0385). Adjustment for potential confounding f actors using multiple linear regression analysis resulted in diminution of the associations between foot skin temperature and sensory neuropathy or or thostatic blood pressure drop, but the latter association remained statisti cally significant in the right foot. Diabetic veterans with sensory or auto nomic neuropathy do not have higher foot skin temperature. Our results sugg est that skin temperature may be slightly lower with higher orthostatic blo od pressure fall. Other causes exist for the frequently observed difference s in skill temperature in the feet of diabetic subjects. (C) 2001 Elsevier Science Inc. All rights reserved.