A study of peripheral diabetic neuropathy. The application of age-related reference values.
The standardization of methodology and the provision of age-related reference values have been addressed for the design of and interpretation of data from a multicentre neuropathy trial. Age-related reference values were generated from 120 healthy volunteers. Vibration perception thresholds (VPT) deteriorated significantly with age (p less than 0.001). Patients were selected on the basis of age-related abnormal VPT and peroneal motor nerve conduction velocity. They were assessed at the beginning and end of a placebo run-in period (baseline data). The coefficients of variation (CV%) for VPT at the medial malleolus (16.81 per cent, n = 316) and great toe (19.23 per cent, n = 313) were lower compared to results in healthy volunteers (29.7 per cent and 20.8 per cent, respectively, n = 49). The CV% for expiratory:inspiratory (E:I) ratio (4.82 per cent, n = 215), Valsalva manoeuvre (10.84 per cent, n = 249) and 30:15 ratio (7.73 per cent, n = 292) from patients corresponded to those recorded in volunteers (7.6 per cent, n = 45 11.0 per cent, n = 49 9.5 per cent, n = 48, respectively). Most patient values for VPT at the great toe fell beyond the 95 centile line for volunteers. E:I ratio for volunteers showed a more variable relationship with age, although patient values appeared to be located below the 5 centile line for volunteer data.
Armstrong
F M
FM
Medical Research Department, ICI Pharmaceuticals plc, Macclesfield, UK.
Bradbury
J E
JE
Ellis
S H
SH
Owens
D R
DR
Rosen
I
I
Sonksen
P
P
Sundkvist
G
G
D000328:Adult; D000367:Age Factors; D000368:Aged; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009431:Neural Conduction; D009460:Neurologic Examination; D010525:Peripheral Nerves / Q000502:physiology / Q000503:physiopathology*; D012016:Reference Values; D012677:Sensation