Cardiac, sudomotor autonomic dysfunction in diabetes improve after bariatric surgery
NASHVILLE, Tenn. — Bariatric surgery restored some cardiac autonomic and sudomotor peripheral C-fiber function in patients with obesity and diabetes, according to data presented here.
Cardiac and sudomotor autonomic dysfunction are predictors of mortality in diabetes, and restoration of nerve function is rare, according to researchers.
“We proposed that the mechanisms by which bariatric surgery improve diabetes and cardiovascular mortality could be related in part to improvements in autonomic function,”
Carolina M. Casellini, MD, a research associate at Eastern Virginia Medical School in Norfolk, said in an oral presentation.
For this preliminary report from their ongoing study, Casellini and colleagues evaluated data from 35 patients undergoing vertical sleeve gastrectomy (n = 24) or Roux-en-Y gastric bypass (n = 11). Researchers took anthropomorphic measurements. Neuropathy in the hands and feet was assessed using a device that measures galvanic skin response (Sudoscan, Impeto Medical); other tests included neurologic impairment score of the lower legs, time- and frequency-dependent cardiac autonomic function tests, quantitative sensory tests, cold and warm perception threshold assessments and sural nerve conduction studies. Tests were conducted at baseline and at 12 and 24 weeks after surgery.
Significant improvements in neuropathy were evidenced by increases in electrochemical skin conductance (ESC) in hands (baseline, 61.73 ESC units; 12 weeks, 67.01 ESC units; 24 weeks, 70.76 ESC units; P < .0001) and feet (baseline, 56.38 ESC units; 24 weeks, 62.01 ESC units; P < .05).
Participants also had significant improvements in neurologic and autonomic function tests at weeks 12 and 24, and in body weight, BMI and body fat percentage, according to researchers.
Improvements in ESC of the feet at week 24 were greater in patients with type 2 diabetes (mean increase, 17.67 ESC units), who had abnormal ESC at baseline, compared with patients without diabetes (mean increase, 4.9 ESC units). ESC of the feet was significantly correlated with body fat percentage. Improvements were comparable between types of surgery.
“Sudomotor function was independently associated with levels of HbA1c, insulin [resistance] and [homeostasis model assessment] index,” Casellini said. – by Jill Rollet
Reference:
Vinik A, et al. Abstract #226. Presented at: AACE 24th Annual Scientific & Clinical Congress; May 13-17, 2015; Nashville, Tenn.
Disclosure: This study was funded by Impeto Medical.