PMP22 and diabetes mellitus: Although the highest OR was found in CIDP+DM patients fulfilling EFNS/PNS criteria (3.73, p = 0.01), with treatment response rates increasing consistently from 27% to 100% in concordance with the number of EFNS criteria fulfilled, in CIDP-DM patients only a trend was observed with a lower OR (OR = 1.53, p = 0.05).