Autonomic symptoms and diabetic neuropathy: a population-based study.
OBJECTIVE
The prevalence of autonomic symptoms and deficits in certain systems is known, but a comprehensive autonomic symptom profile in diabetes is not available. We aimed to estimate this using a laboratory evaluation of autonomic function and a validated self-report measure of autonomic symptoms in patients and matched control subjects from the population-based Rochester Diabetic Neuropathy Study.


METHODS
Participants included 231 patients with diabetes (type 1, n=83; type 2, n=148) and 245 healthy age-matched control subjects. We assessed symptoms using a validated self-report instrument (Autonomic Symptom Profile) and evaluated the severity and distribution of autonomic deficits (cardiovagal, sudomotor, adrenergic) with the objective, laboratory-based Composite Autonomic Severity Score (CASS).


RESULTS
Autonomic symptoms were present more commonly in type 1 than in type 2 diabetes, with symptoms of orthostatic intolerance, secretomotor, urinary control, diarrhea, and sleep disturbance and pupillomotor, vasomotor, and erectile dysfunction significantly increased over healthy control subjects in type 2 diabetic patients. The prevalence of autonomic impairment was 54% in type 1 and 73% in type 2 diabetic patients. Severity of autonomic failure was mild overall (mean CASS 2.3; maximum 10), with orthostatic hypotension occurring in 8.4 and 7.4% of type 1 and 2 diabetic patients, respectively. Fourteen percent of patients had a CASS > or =5, indicating moderate to severe generalized autonomic failure. The correlation of symptoms with autonomic deficits (CASS) was better in type 1 than type 2 diabetic subjects and was weak overall.


CONCLUSIONS
These findings indicate that autonomic symptoms and deficits are common in diabetes, but mild in severity, and that the correlation between symptom scores and deficits is overall weak in mild diabetic neuropathy, emphasizing the need to separately evaluate autonomic symptoms.
Low
Phillip A
PA
Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA. low@mayo.edu
Benrud-Larson
Lisa M
LM
Sletten
David M
DM
Opfer-Gehrking
Tonette L
TL
Weigand
Stephen D
SD
O'Brien
Peter C
PC
Suarez
Guillermo A
GA
Dyck
Peter J
PJ
D001342:Autonomic Nervous System Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D016208:Databases, Factual; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012720:Severity of Illness Index