Endocrine Abstracts

Background: Diabetic neuropathy (DN) is the most common chronic diabetes complication in type 1 (T1DM) and type 2 (T2DM) diabetes mellitus. Due to diagnostic issues, it is the least studied complication with limited and controversial data about the differences of various types of DN between T1DM and T2DM patients.

Aim: To evaluate the differences of diabetic polyneuropathy (DPN) and cardiac autonomic neuropathy (CAN) - between T1DM and T2DM patients.

Materials and Methods: Three methods were used to evaluate DPN: clinical examination was done using neuropathy symptom score (NSS) and neuropathy disability score (NDS); neurometry (NM) – using Neurometer NervScan™ LLC device; electroneurography (ENG) – using Nihon Kohden Neuropack M-1 Electromyogram Machine. CAN was assesed by performing cardiovascular autonomic reflex tests (CARTS) using Cardiosys Extra MDE diagnostic device.

Results: There were 53 T1DM and 63 T2DM patients enroled in to the study. T1DM patients were significantly (P<0,05 for all) younger (41,6 ± 15,9 vs 60,0 ± 11,7 years), had lower BMI (23,5±3,5 vs 36,0±6,32 kg/m2), systolic and diastolic blood pressure (124,5±16,3 vs 138,7±13,7 and 74,2±8,9 vs 80,5±8,3 mmHg respectively), incidence of arterial hypertension (35,8% vs 90,5%), heart failure (3,8% vs 20,6%) and coronary artery disease (5,7% vs 20,6%). T2DM patients had significantly higher scores of symptomatic neuropathy compared to T1DM (NSS 4,3 ± 3,3 vs 3,1±3,4; P<0,049), but the severity of pain, evaluted by self reported numerical rating scale did not differ (1,8 ± 2,5 vs 1,4 ±2,5, P=0,17). The prevalenceof DPN did not differ between the groups, however the proportion of DPN depended on method used, being the highest diagnosed with NM (67,3% vs 61,3%, P>0,05), followed by ENG (40,9% vs 44,1%, P>0,05) and clinical examination (30,2% vs 35,5, P>0,05). Tuning fork vibration perception was the only test of clinical evaluation that showed significantly worse vibration perception in T2DM patients compared with T1DM (impaired in 78,3% vs 57,1%, P=0,023), CARTs showed significantly higher incidence of CAN in T2DM compared to T1DM patients (67,3% vs 32,7%, P=0,011).

Conclusions: There was no difference in the prevalence of DPN between T1DM and T2DM, however significant difference in diagnostic accuracy of different methods was observed. T2DM patients were more likely to have symptomatic polyneuropathy, large fiber damage and CAN.