Conduction studies as prognostic parameters in the natural history of diabetic neuropathy: a long-term follow-up of 114 patients.
In order to evaluate the clinical and prognostic role of common neurophysiological parameters, we examined 114 patients selected from a population of 2500 diabetics, observed in the period 1973-1986. The follow-up lasted 9 to 16 years (mean = 10). For prognostic purposes the patients were divided into 3 groups according to the motor conduction velocity (MCV) of the peroneal nerve: A) 47 cases with normal MCV (more than 44 m/s); B) 38 cases with mild neuropathy (MCV between 44 and 39 m/s); C) 29 cases with severe neuropathy (MCV less than 39 m/s). The natural history was evaluated on the basis of the following parameters: neurological symptom score (NSS), neurological disability score (NDS), patient's self-evaluation (PE) and neurologist's evaluation (ME). At the initial examination, there was a significant correlation between MCV and NDS/ME. At the final examination, MCV was reduced to groups A and B, unchanged in group C. NSS, NDS, PE and ME were worsened, but a significant correlation was found only between MCV and NDS: neuropathic groups (B and C) showed a more severe evolution than the normal group (A). In conclusion, a) MCV is progressively reduced as diabetes evolves, but--once it has reached a plateau--it stabilizes; b) MCV only has a prognostic value when it is considered together with clinical neurological signs.
Negrin
P
P
Neurological Department, University of Padua, Italy.
Zara
G
G
D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology; D018908:Muscle Weakness / Q000503:physiopathology; D009431:Neural Conduction; D009460:Neurologic Examination; D009482:Neurophysiology; D010523:Peripheral Nervous System Diseases / Q000503:physiopathology; D010543:Peroneal Nerve / Q000503:physiopathology; D011379:Prognosis; D012026:Reflex, Stretch / Q000502:physiology; D012647:Self-Assessment; D012678:Sensation Disorders / Q000503:physiopathology