title: Insulin resistance is associated with digital ulcer in patients with systemic sclerosis.
abstract: OBJECTIVE
  To investigate the relationship between insulin resistance and digital ulcers (DUs) in patients with systemic sclerosis (SSc).
  
  
  METHODS
  Using a cross-sectional design, we recruited 73 consecutive female patients with SSc and 109 sex- and age-matched healthy controls in South Korea from July 2014 to June 2015. The magnitude of insulin resistance was measured using the homeostatic model assessment of insulin resistance (HOMA-IR). DUs ever included active and healed DUs and the extent of skin fibrosis was evaluated using the modified Rodnan skin score (MRSS).
  
  
  RESULTS
  The HOMA-IR in patients with SSc was significantly higher than that in healthy controls (median 1.18 vs. 0.71, p<0.001). In SSc patients, 7 (9.6%) had active DUs and 14 subjects (19.2%) had healed DUs; thus, DUs ever were observed in 21 cases (28.8%). SSc patients with DUs ever had significantly higher HOMA-IR and MRSS compared with those without this feature (median, 2.05 vs. 0.99, p=0.001 and 14 vs. 9.5, p=0.011, respectively). After adjustment for confounding factors using multivariable logistic regression analyses, the HOMA-IR showed a significant positive association with the presence of DUs ever in patients with SSc (OR=1.43, 95% CI=1.01-2.05, p=0.048). In addition, higher MRSS was significantly correlated with DUs ever (OR=1.11, 95% CI=1.02-1.21, p=0.015).
  
  
  CONCLUSIONS
  Insulin resistance was independently associated with the presence of DUs in patients with SSc and may be a potential biomarker for SSc micro-vasculopathy. Moreover, our data also suggest a potential contribution of insulin resistance to the pathogenesis of DUs.
authors.affiliation: Divsion of Rheumatology, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Eun-Kyoung
authors.initials: EK
authors.lastname: Park
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea. sglee@pusan.ac.kr.
authors.forename: Seung-Geun
authors.initials: SG
authors.lastname: Lee
authors.affiliation: Divsion of Endocrinology and Metabolism, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Bo-Hyun
authors.initials: BH
authors.lastname: Kim
authors.affiliation: Divsion of Rheumatology, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Ji-Heh
authors.initials: JH
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Medical Research Institute, Pusan National University Hospital, Busan, South Korea.
authors.forename: Shinwon
authors.initials: S
authors.lastname: Lee
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Kosin University College of Medicine, Busan, South Korea.
authors.forename: Geun-Tae
authors.initials: GT
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D005355:Fibrosis; D005385:Fingers; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D056910:Republic of Korea; D012307:Risk Factors; D012595:Scleroderma, Systemic / Q000097:blood / Q000150:complications* / Q000175:diagnosis; D012867:Skin / Q000098:blood supply / Q000473:pathology*; D012883:Skin Ulcer / Q000097:blood / Q000209:etiology* / Q000473:pathology; D014945:Wound Healing; D055815:Young Adult
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D007328:Insulin