Subgroup comparison of 174 symptomatic patients with DPN to 88 patients with symptomatic IPN
| Neuropathy measures*† | Symptomatic DPN | Symptomatic IPN | P value‡ | P value§ |
| (n=174) | (n=88) | Univariate analysis | Multivariate analysis | |
| UENS total score | 10.0 (5.0–18.0) | 8.0 (3.0–14.0) (1) | <0.01 | 0.3 |
| NSS | ||||
| Bulbar paresis | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) (1) | 0.02 | |
| Extremity paresis | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) (1) | 0.16 | |
| Sensory positive | 2.0 (2.0–2.0) | 2.0 (1.0–2.0) (1) | <0.01 | |
| Sensory negative | 0.0 (0.0–1.0) | 0.0 (0.0–1.0) (1) | <0.001 | |
| Autonomic | 1.0 (0.0–1.0) | 0 (0.0–0.0) (1) | <0.0001 | |
| Total | 3.0 (2.1–4.3) | 2.1 (2.0–3.2) (1) | <0.0001 | <0.001 |
| NPSI¶ | ||||
| Total score | 28.0 (13.5–42.5) (1) | 28.0 (15.0–39.0) (1) | 0.65 | 0.43 |
| Evoked pain | 6.0 (0.0–12.0) (1) | 3.0 (0.0–8.0) (1) | 0.09 | 0.06 |
| Pain, n (%) | 97 (55.8) | 52 (59.1) | 0.61 | 0.95 |
| QST, n (%) (missing) | ||||
| Increased VDT | 88 (53.7) (10) | 61 (69.3) | 0.02 | <0.01 |
| Increased MDT | 61 (35.7) (2) | 35 (39.8) | 0.52 | 0.21 |
| Increased CDT and/or WDT | 55 (32.2) (3) | 33 (37.5) | 0.4 | 0.35 |
| DMA | 13 (7.5) | 28 (20.5) | <0.01 | 0.01 |
| Increased MPS | 11 (6.4) (3) | 16 (18.2) | <0.01 | 0.03 |
| IENFD (fibres/mm) | 3.1 (1.2–5.3) (27) | 4.9 (3.6–6.2) | <0.0001 | <0.001 |
| Abnormal IENFD, n (%) (missing) | 80 (54.4) (27) | 26 (29.6) | <0.001 | <0.001 |
| Abnormal NCS, n (%) (missing) | 59 (34.5) (3) | 35 (39.8) | 0.4 | 0.06 |
*All categorical variables are stated as frequency with percentage in parentheses and missing in parentheses if present, n (%) (missing).
†All interval variables are stated as median with IQR between brackets and missing between parentheses if present, median (IQR) (missing).
‡P<0.05 chosen as level of significance. Rank-sum test, χ2 test, and Fisher’s exact test were used as appropriate.
§P<0.05 chosen as level of significance. Linear regression is used for interval variables and logistic regression for categorical variables with adjustment for age, sex and duration of neuropathy symptoms for all variables.
¶NPSI total score for 97 patients with DPN and 52 patients IPN with distal pain in both feet.
CDT, cold detection threshold; DMA, dynamic mechanical allodynia; DPN, diabetic polyneuropathy; IENFD, intraepidermal nerve fibre density; IPN, idiopathic polyneuropathy; MDT, mechanical detection threshold; MPS, mechanical pain sensitivity; NCS, nerve conduction study; NPSI, Neuropathic Pain Symptom Inventory; NSS, Neuropathy Symptom Score; QST, quantitative sensory testing; UENS, Utah Early Neuropathy Score; VDT, vibration detection threshold; WDT, warmth detection threshold.