Effect of Glycemic Control on Sudomotor Denervation in Type 2 Diabetes

    loading  Checking for direct PDF access through Ovid

Abstract

OBJECTIVE

Sudomotor symptoms are a common component of diabetic autonomic neuropathy, but the pathology of sudomotor innervation and its relationship with glycemic control have remained obscured.

RESEARCH DESIGN AND METHODS

We enrolled 42 patients (26 males and 16 females aged 56.64 ± 12.67 years) with diabetic neuropathy defined by symmetric distally predominant sensory symptoms, abnormal nerve conduction studies, and reduced intraepidermal nerve fiber density in the leg. Skin biopsies of the distal leg were immunostained with antiprotein gene product 9.5 for nerve fibers and counterstained with Congo red for sweat glands. Sweat gland innervation index (SGII) was quantified with a new computerized area-based morphometric system.

RESULTS

Protein gene product 9.5(+) nerve terminals surrounded secretory coils of the sweat glands in the skin of control subjects. Sudomotor denervation was present in diabetic patients, manifesting as depletion of periglandular nerve fibers with lower SGII compared with 42 age- and sex-matched control subjects (2.54 ± 1.87 vs. 4.68 ± 1.51%, P < 0.001). The SGII was correlated with HbA1c (P = 0.011) and was lower in patients with anhidrosis of the feet compared with those with normal sweating of the feet (0.82 ± 0.69 vs. 3.00 ± 1.81%, P = 0.001). Sudomotor denervation was concordant with cardiac autonomic dysfunction as assessed with reduced heart rate variability (P = 0.003).

CONCLUSIONS

Sudomotor denervation is a significant presentation of diabetic neuropathy, and the SGII was associated with HbA1c. A skin biopsy offers a structural assessment of sudomotor innervation.

Related Topics

    loading  Loading Related Articles