Control (n=51) | T1DM (n=48) | T1DM with NP-DPN (n=67) | T1DM with P-DPN (n=50) | P value | P value (NP-DPN vs P-DPN) | |

Pinprick, neurotip (abnormal) | 1 (2.0%) | 1 (2.1%) | 30 (44.8%) | 30 (60.0%) | 0.000* | 0.135 |

10 g neurofilament, neuropen (abnormal) | 0 (0.0%) | 1 (2.1%) | 35 (52.2%) | 30 (60.0%) | 0.000* | 0.455 |

Temperature sensitivity (abnormal) | 2 (4.0%) | 9 (19.6%) | 48 (72.7%) | 36 (75.0%) | 0.000* | 0.832 |

Biothesiometer average (V) | 6.7 (5.0; 9.9) | 9.9 (5.5; 13.9) | 27.7 (17.2; 41.7) | 30.9 (18.7; 47.8) | 0.000* | 0.147 |

PainDETECT score | 0.0 (0.0; 0.0) | 0.0 (0.0; 0.0) | 0.0 (0.0; 1.0) | 15.0 (10.0; 22.0) | 0.000* | 0.000* |

MNSI questionnaire score | 2.0 (2.0; 3.0) | 3.0 (2.0; 4.0) | 5.0 (4.0; 6.0) | 8.0 (7.0; 10.0) | 0.000* | 0.000* |

MNSI clinical score | 0.0 (0.0; 1.0) | 0.5 (0.0; 1.5) | 4.0 (3.0; 6.0) | 5.0 (3.0; 6.0) | 0.000* | 0.170 |

TCNS score | 0.0 (0.0; 1.0) | 1.0 (0.0; 2.0) | 6.0 (3.0; 9.0) | 9.0 (7.0; 12.0) | 0.000* | 0.000* |

Categorical variables: presented as number of

*x*and its percentage within each group. Continuous variables: presented as median with the 25th and 75th quartile within each group. All-group comparisons (p value) were carried out using Fisher’s exact test (categorical variables) and Kruskal-Wallis H test (continuous variables). Two-group comparisons between T1DM with NP-DPN and T1DM with P-DPN (p value (NP-DPN vs P-DPN)) were carried out using Fisher’s exact test (categorical variables) and Mann-Whitney U test (continuous variables).*p<0.001.

MNSI, Michigan neuropathy screening instrument; NP-DPN, non-painful diabetic polyneuropathy; P-DPN, painful diabetic polyneuropathy; TCNS, Toronto Clinical Neuropathy Score; T1DM, type 1 diabetes mellitus.