Treatment responsiveness in CIDP patients with diabetes is associated with unique electrophysiological characteristics, and not with common criteria for CIDP

Objectives: Characterize treatment responsiveness in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) patients with diabetes mellitus (DM). Methods: We performed a retrospective chart review of CIDP subjects assessed between 1997 and 2013 and compared treatment response rates in those with and without DM, using different sets of criteria. Results: 99 CIDP patients were included, 34 CIDP+DM and 65 CIDP-DM patients, both having similar treatment response rates. CIDP patients fulfilling European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) criteria had higher treatment response rates. Responders fulfilled a higher number of American Academy of Neurology (AAN) and EFNS/PNS criteria and had a higher number of demyelinating features in the total cohort and in CIDP-DM but not in CIDP+DM patients. CIDP+DM responders, however, had unique electrophysiologic characteristics. Conclusion: Fulfilling EFNS/PNS and AAN criteria, and higher number of demyelinating features, are associated with higher treatment response rates in CIDP-DM but not in CIDP+DM patients, implying the need for adjusting current criteria to predict treatment response rates in CIDP-DM patients.