Incidence and prevalence of CIDP and the association of diabetes mellitus.
BACKGROUND
The reported prevalence of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) varies greatly, from 1.9 to 7.7 per 100,000. CIDP is reported to occur more commonly in patients with diabetes mellitus (DM) but has not been rigorously tested.


OBJECTIVE
To determine the incidence (1982-2001) and prevalence (on January 1, 2000) of CIDP in Olmsted County, Minnesota, and whether DM is more frequent in CIDP.


METHODS
CIDP was diagnosed by clinical criteria followed by review of electrophysiology. Cases were coded as definite, probable, or possible. DM was ascertained by clinical diagnosis or current American Diabetes Association glycemia criteria.


RESULTS
One thousand five hundred eighty-one medical records were reviewed, and 23 patients (10 women and 13 men) were identified as having CIDP (19 definite and 4 probable). The median age was 58 years (range 4-83 years), with a median disease duration at diagnosis of 10 months (range 2-64 months). The incidence of CIDP was 1.6/100,000/year. The prevalence was 8.9/100,000 persons on January 1, 2000. Only 1 of the 23 CIDP patients (4%) also had DM, whereas 14 of 115 age- and sex-matched controls (12%) had DM.


CONCLUSIONS
1) The incidence (1.6/100,000/year) and prevalence (8.9/100,000) of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) are similar to or higher than previous estimates. 2) The incidence of CIDP is similar to that of acute inflammatory demyelinating polyradiculoneuropathy within the same population. 3) Diabetes mellitus (DM) is unlikely to be a major risk covariate for CIDP, but we cannot exclude a small effect. 4) The perceived association of DM with CIDP may be due to misclassification of other forms of diabetic neuropathies and excessive emphasis on electrophysiologic criteria.
Laughlin
R S
RS
Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA.
Dyck
P J
PJ
Melton
L J
LJ
Leibson
C
C
Ransom
J
J
Dyck
P J B
PJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D015897:Comorbidity; D048909:Diabetes Complications / Q000453:epidemiology* / Q000378:metabolism / Q000503:physiopathology; D003920:Diabetes Mellitus / Q000453:epidemiology* / Q000378:metabolism / Q000503:physiopathology; D004568:Electrodiagnosis; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008910:Minnesota; D009431:Neural Conduction / Q000502:physiology; D010525:Peripheral Nerves / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D020277:Polyradiculoneuropathy, Chronic Inflammatory Demyelinating / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D015995:Prevalence; D012307:Risk Factors; D055815:Young Adult