Table 3.
Effects of individual covariates on decreasing neurophysiologic and examination function (expressed as F-statistics)
| Test | SBP | Smoking | DM type | DM Duration | Age | BMI | A1C | Cholesterol | Triglycerides |
|---|---|---|---|---|---|---|---|---|---|
| Quantitative Sensory Testing | |||||||||
| Vibration thumb | 0.8 | 11.7* | 0.2 | 0.1 | 0.4 | 0.5 | 0.3 | 1.3 | 0.1 |
| Vibration toe | 0.6 | 4.4 | 0.6 | 0.5 | 1.2 | 0.4 | 0.3 | 7.6 | 0.3 |
| Cold detection hand | 0.7 | 0.7 | 0.1 | 0 | 0.2 | 0.2 | 0.6 | 0 | 0 |
| Cold detection foot | 0.3 | 2.6 | 0 | 2.4 | 0.2 | 0 | 0.2 | 0.9 | 0.6 |
| Warm detection hand | 3.9 | 2.3 | 0.8 | 2.3 | 0.5 | 0 | 1.7 | 7.6 | 3.5 |
| Warm detection foot | 7.4 | 8.6* | 2.6 | 18.5* | 2.2 | 1.3 | 3.5 | 0.8 | 4.1 |
| Cold pain detection hand | 0.2 | 0 | 2.1 | 4.5 | 0.6 | 0.7 | 0.7 | 2.9 | 2.1 |
| Cold pain detection foot | 2.7 | 0.1 | 0.8 | 0 | 0.6 | 0 | 0 | 4.3 | 0 |
| Heap pain detection hand | 1.3 | 0.1 | 0.5 | 1.7 | 0.2 | 0.9 | 1.0 | 9.1* | 2.3 |
| Heat pain detection foot | 1.0 | 13.6* | 0.2 | 2.2 | 0.3 | 1.2 | 1.7 | 0.7 | 8.4* |
| Autonomic Testing | |||||||||
| Heart rate variability | 7.3 | 0 | 5.6 | 0.1 | 25.3* | 0 | 1.2 | 1.1 | 1.1 |
| Valsalva ratio | 0 | 0 | 2.6 | 0.7 | 41.2* | 0.1 | 4.3 | 0.1 | 0.1 |
| Valsalva blood pressure fall | 12.7* | 0.1 | 0 | 0 | 3.9 | 3.2 | 0.2 | 1.3 | 0.2 |
| Valsalva blood pressure Recovery | 0.1 | 1.3 | 0.4 | 0.1 | 8.7* | 1.2 | 1.7 | 1.8 | 0 |
| Valsalva phase 4 overshoot | 3.9 | 0 | 0.1 | 0.2 | 4.2 | 1.5 | 0.2 | 1.2 | 0.3 |
| Tilt blood pressure change | 12.0* | 6.8 | 1.5 | 0.4 | 6.4 | 0.3 | 6.9 | 2.3 | 4.2 |
| Tilt heart rate change | 0 | 0 | 0.1 | 3.0 | 8.7* | 0.2 | 1.1 | 0.5 | 0 |
| Nerve Conduction Studies | |||||||||
| Sural amplitude | 4.9 | 5.2 | 1.6 | 1.9 | 7.1 | 9.6* | 4.0 | 0.5 | 0.5 |
| Sural velocity | 7.1 | 4.4 | 0 | 4.5 | 1.0 | 0.3 | 0.8 | 3.9 | 0.3 |
| Peroneal amplitude | 5.3 | 3.8 | 0.6 | 2.9 | 0.4 | 0 | 0.2 | 1.1 | 0.1 |
| Peroneal velocity | 1.5 | 4.3 | 3.1 | 0.3 | 1.0 | 0.6 | 2.0 | 3.0 | 0.4 |
| Peroneal distal latency | 1.6 | 0.8 | 0.2 | 1.0 | 0.9 | 0.8 | 0 | 1.2 | 0.8 |
| Laser Doppler Imaging | |||||||||
| Arm %change indirect | 0.1 | 0.1 | 0 | 0.1 | 0.4 | 0 | 0 | 0.1 | 0.1 |
| Foot %change indirect | 0 | 0 | 0.4 | 0.4 | 7.7 | 2.5 | 0.1 | 0.5 | 0.1 |
| Examination & Symptoms | |||||||||
| NDS | 0.2 | 0.5 | 0 | 4.6 | 3.3 | 0.1 | 4.4 | 3.3 | 0.1 |
| NSS | 0.1 | 0.7 | 0.9 | 4.8 | 0 | 0.1 | 0 | 0.3 | 0.2 |
| Monofilament | 0 | 0.4 | 0.2 | 4.3 | 5.9 | 0.2 | 1.6 | 4.0 | 0.2 |
The results for each test visit were compared by repeated measured ANOVA with all covariates listed above. The results are expressed as F statistics, where larger numbers are more strongly correlated with declining neurophysiologic function. F-statistics > 3.7 are significant at p<0.05, and are shown in bold type;
*
F-statistics >8.1, significant at p<0.001 (i.e. significant with bonferroni correction for multiple comparisons). NDS: neuropathy disability score. NSS: neuropathy symptom score.