Hyposensitivity of C-fiber afferents at the distal extremities as an indicator of early stages diabetic bladder dysfunction in type 2 diabetic women.
OBJECTIVE
To investigate the relationship between distal symmetric peripheral neuropathy and early stages of autonomic bladder dysfunction in type 2 diabetic women.


METHODS
A total of 137 diabetic women with minimal coexisting confounders of voiding dysfunction followed at a diabetes clinic were subject to the following evaluations: current perception threshold (CPT) tests on myelinated and unmyelinated nerves at the big toe for peroneal nerve and middle finger for median nerve, uroflowmetry, post-void residual urine volume, and overactive bladder (OAB) symptom score questionnaire. Patients presenting with voiding difficulty also underwent urodynamic studies and intravesical CPT tests.


RESULTS
Based on the OAB symptom score and urodynamic studies, 19% of diabetic women had the OAB syndrome while 24.8% had unrecognized urodynamic bladder dysfunction (UBD). The OAB group had a significantly greater mean 5 Hz CPT test value at the big toe by comparison to those without OAB. When compared to diabetic women without UBD, those with UBD showed greater mean 5 Hz CPT test values at the middle finger and big toe. The diabetic women categorized as C-fiber hyposensitivity at the middle finger or big toe by using CPT test also had higher odds ratios of UBD. Among diabetic women with UBD, the 5 Hz CPT test values at the big toe and middle finger were significantly associated with intravesical 5 Hz CPT test values.


CONCLUSIONS
Using electrophysiological evidence, our study revealed that hyposensitivity of unmyelinated C fiber afferents at the distal extremities is an indicator of early stages diabetic bladder dysfunction in type 2 diabetic women. The C fiber dysfunction at the distal extremities seems concurrent with vesical C-fiber neuropathy and may be a sentinel for developing early diabetic bladder dysfunction among female patients.
Division of Urology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan ; Graduate Institution of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.
Wei-Chia
WC
Lee
Department of Urology, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Chiayi, Taiwan.
Han-Ching
HC
Wu
Department of Urology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.
Kuo-How
KH
Huang
Department of Internal Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.
Huey-Peir
HP
Wu
Department of Urology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.
Hong-Jeng
HJ
Yu
Department of International Business, College of Commerce and Management, Cheng Shiu University, Kaohsiung, Taiwan.
Chia-Ching
CC
Wu
D000344:Afferent Pathways; D000368:Aged; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D004558:Electric Stimulation; D005260:Female; D005385:Fingers / Q000294:innervation; D006801:Humans; D008875:Middle Aged; D036421:Nerve Fibers, Unmyelinated / Q000502:physiology; D010465:Perception; D014034:Toes / Q000294:innervation; D014549:Urinary Incontinence / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*