489-P: Abnormal Combined Point-of-Care-Device DPN-Check and SUDOSCAN Results Predict All-Cause Mortality in People with Diabetes

Aims: Diabetic peripheral neuropathy (DPN) has been associated with increased mortality; however, data is not available for objectively diagnosed DPN using point-of-care-devices (POCDs). We therefore examined the predictive validity of POCD-diagnosed DPN for increased mortality in a prospective study.

Methods: A total of 245 consecutive people with diabetes (17 type 1 diabetes, age 62.3+14.3) attending retinal-screening had all annual review health checks in a One-stop Screening Service. DPN assessments included Toronto Clinical Neuropathy Score (TCNS) evaluation, 10g-monofilament test(10g-MFT) and two validated, objective POCDs, DPN-Check (handheld device measuring sural nerve conduction velocity/amplitude), and SUDOSCAN (measuring sudomotor function). Mortality data was collected at 7-year follow-up. Kaplan-Meier survival curves and Cox-proportional hazards models were generated to assess associations of DPN measures with all-cause mortality.

Results: At follow-up, 52 [21.2% (SE 6.8%)] had died. Those who died were older at screening [72.4 (10.9) vs 59.6 (13.9) years; (p<0.001)]. The prevalence of screen-detected DPN was 12.6% (SE 4.4%) for 10g-MFT, 27.7% (SE 8.2%) for TCNS and 33.4% (SE 9.1%) for combined POCDs. In crude Kaplan-Meier analyses all-cause mortality risk was greater in patients with abnormal TCNS (p<0.001) and POCDs (p<0.001) but was equivalent in patients with normal or abnormal 10g-MFT (p=0.21). After adjusting for age, HbA1c and Total Cholesterol, only abnormal POCDs was significantly associated with all-cause mortality [HR 1.18 (p=0.04, 95%CI 1.00:1.39) vs TCNS [HR 1.33 (p=0.06, 95%CI 0.99:1.78)].

Conclusions: This is the first prospective study showing abnormal combined DPN-Check and SUDOSCAN results predict all-cause mortality after adjusting for other risk factors. However, 10g-MFT and TCNS that diagnose DPN late did not predict all-cause mortality.