Significance of quantitative thermal testing in the diagnosis of diabetic peripheral neuropathy

Abstract

Objective To investigate the significance of quantitative thermal testing (QTT) in the diagnosis of diabetic peripheral neuropathy. Methods One hundred and sixty-nine diabetic patients with neurological deficit (DM group) and 53 age-matched healthy controls underwent the determination of cold threshold (CT), warm threshold (WT), clod pain threshold (CPT), warm pain threshold (WPT) in both dorsum of hand and dorsum of foot. DM group were divided into subgroups with a course of disease > 5 years or with a course of disease ≤ 5 years, or divided into subgroups with normal or abnormal nerve conduction study (NCS). Results CT and WT of DM group with a course of disease ≤ 5 years ((29.6 ± 1.4), (26. 5±4. 3) ℃ ; (35.9±3.0), (41.3±4. 0) ℃) were higher than the health controls' ((30. 2±1.2), (29.1±1.5) ℃; (35.0±1.9), (36.5±1.5) ℃, respectively; t=3.27, 6.63, 2.80, 8.61, all P 5 years' ((28. 2±4. 0), (23. 1 ±7.9) ℃ ; (37.0±4. 7), (42. 6±4. 2) ℃, respectively) were higher than the DM group with course of disease≤ 5 years(t =4. 09, 4.63, 2.55, 2. 68 ,all P 5 years were higher than these in DM group with a course of disease ≤5 years; the frequency of abnormal WT in DM group(86. 4% ,146/169)was higher than that of CT in DM group(68. 1% ,115/169,x2=15.49, P<0.01), the frequency of abnormal QTT in the dorsum of foot in DM group was higher than that in the dorsum of hand in the DM group. PT of diabetic patients were higher than that in the healthy controls. Condusions QTT is more sensitive than NCS in the diagnosis diabetic peripheral neuropathy, which is neeossary to assist NCS when diabetic peripheral neuropathy is suspected, WT in dorsum of foot is a sensitive parameter in the diagnosis of diabetic peripheral neuropathy. Key words: Diabetic neuropathies; Peripheral nervous system diseases; Temperature sense; Sensory thresholds; Neural conduction