title: Neuropad for the detection of cardiovascular autonomic neuropathy in patients with type 2 diabetes.
abstract: BACKGROUND
  Cardiovascular autonomic neuropathy (CAN) is a prevalent and neglected chronic complication of diabetes, with a large impact on morbidity and mortality. Part of the reason why it is not detected and treated opportunely is because of the complexity of the tests required for its diagnosis. We evaluated the Neuropad®, a test based on sudomotor function, as a screening tool for CAN in adult patients with type 2 diabetes in Bogotá, Colombia.
  
  
  METHODS
  This was a cross-sectional evaluation of Neuropad® for the detection of CAN. Patients were 20-75years of age and did not suffer from any other type of neuropathy. CAN was diagnosed using the Ewing battery of tests for R-R variability during deep breathing, Valsalva and lying-to-standing maneuvers. Additionally, distal symmetric polyneuropathy (DSP) was diagnosed using a sign-based scale (Michigan Neuropathy Disability Score - NDS) and a symptom-based score (Total Symptom Score - TSS). The primary outcome was the sensitivity and specificity of the Neuropad® for the diagnosis of CAN, and secondary outcomes were the sensitivity and specificity of Neuropad® for DSP.
  
  
  RESULTS
  We studied 154 patients (74 men and 80 women). Prevalence of CAN was extremely high (68.0% of study participants), but also DSP was prevalent, particularly according to the signs-based definition (45%). The sensitivity of the Neuropad® for any degree of CAN was 70.1%, being slightly higher for the deep breathing and Valsalva tests than for lying-to-standing. The specificity of the Neuropad® for any type of CAN was only 37.0%, as expected for a screening exam. The negative predictive value was higher for the deep breathing and Valsalva tests (69.4 and 81.6%, respectively). Neuropad showed also a good sensitivity and negative predictive value for DSP. The sensitivity and specificity of Neuropad were better among men, and among patients with diabetes duration above the group median.
  
  
  CONCLUSIONS
  The Neuropad is a simple and inexpensive device that demonstrated an adequate performance as a screening tool for cardiovascular autonomic neuropathy in Latin American patients with DM2.
authors.affiliation: Endocrinology Section, Department of Internal Medicine, Fundación Santafé de Bogotá, Bogotá, Colombia; School of Medicine, Universidad de los Andes, Bogotá, Colombia. Electronic address: cmendivi@uniandes.edu.co.
authors.forename: Carlos O
authors.initials: CO
authors.lastname: Mendivil
authors.affiliation: Endocrinology Section, Department of Internal Medicine, Fundación Santafé de Bogotá, Bogotá, Colombia; School of Medicine, Universidad de los Andes, Bogotá, Colombia. Electronic address: wkattah@uniandes.edu.co.
authors.forename: William
authors.initials: W
authors.lastname: Kattah
authors.affiliation: Endocrinology Section, Department of Internal Medicine, Fundación Santafé de Bogotá, Bogotá, Colombia. Electronic address: arturo.orduz@fsfb.org.co.
authors.forename: Arturo
authors.initials: A
authors.lastname: Orduz
authors.affiliation: Endocrinology Section, Department of Internal Medicine, Fundación Santafé de Bogotá, Bogotá, Colombia. Electronic address: claudia.tique@fsfb.org.co.
authors.forename: Claudia
authors.initials: C
authors.lastname: Tique
authors.affiliation: School of Medicine, Universidad de los Andes, Bogotá, Colombia. Electronic address: jl.cardenas3230@uniandes.edu.co.
authors.forename: José L
authors.initials: JL
authors.lastname: Cárdenas
authors.affiliation: School of Medicine, Universidad de los Andes, Bogotá, Colombia. Electronic address: je.patino841@uniandes.edu.co.
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Patiño
mesh_terms: D000328:Adult; D000368:Aged; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001342:Autonomic Nervous System Diseases / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D002319:Cardiovascular System / Q000294:innervation / Q000503:physiopathology*; D003105:Colombia; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D003925:Diabetic Angiopathies / Q000175:diagnosis / Q000503:physiopathology; D003929:Diabetic Neuropathies / Q000175:diagnosis* / Q000503:physiopathology; D003943:Diagnostic Techniques, Neurological / Q000295:instrumentation*; D005260:Female; D005528:Foot; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008875:Middle Aged; D010044:Outpatient Clinics, Hospital; D011115:Polyneuropathies / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D012727:Sex Characteristics; D055815:Young Adult
keywords: Cardiovascular autonomic neuropathy; Complications; Diabetic autonomic neuropathy; Diabetic neuropathy; Diagnostic test