title: Cofactors and comorbidities of necrobiosis lipoidica: analysis of the German DRG data from 2012.
abstract: BACKGROUND
  Necrobiosis lipoidica (NL) is a rare granulomatous inflammatory skin disease of unknown pathophysiology. Its potential association with diabetes mellitus is well known. Other relevant cofactors and comorbidities are subject to controversial debate.
  
  
  METHODS
  DRG (diagnosis-related groups) data of all inpatients with a coded primary or secondary diagnosis of NL treated at German hospitals in 2012 were evaluated.
  
  
  RESULTS
  Data of 262 inpatient cases with the primary or secondary diagnosis of NL were analyzed. Women (63.4%; n = 166) were nearly twice as frequently affected as men (36.2%; n = 96). Most NL patients (14.8%) were in the age group between 50 and 55 years. Among comorbidities included in the metabolic syndrome complex, diabetes mellitus was the most common (34.4%; IDDM 20.6%, NIDDM 13.8%), while essential hypertension was observed in 9.2%, obesity in 4.6%, chronic heart failure in 4.1%, and dyslipidemias in 2.3% of cases. Leg ulcers were diagnosed in 7.3% of individuals; other venous disorders, in 5.7%.
  
  
  CONCLUSIONS
  Our data analysis describes one of the largest compilations of patient cases with the diagnosis of NL worldwide. Besides the well-known association with diabetes mellitus, there are numerous other potentially relevant cofactors and comorbidities that should be considered in the diagnosis and management of NL patients.
authors.affiliation: Department of Dermatology, Venereology, and Allergology, University Hospital Essen, Essen, Germany.
authors.forename: Finja
authors.initials: F
authors.lastname: Jockenhöfer
authors.affiliation: Division of of Angiology, Helios Hospital, Krefeld, Germany.
authors.forename: Knut
authors.initials: K
authors.lastname: Kröger
authors.affiliation: Department of Dermatology, Venereology, and Allergology, University Hospital Essen, Essen, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Klode
authors.affiliation: Department of Dermatology, University Hospital Erlangen, Erlangen, Germany.
authors.forename: Regina
authors.initials: R
authors.lastname: Renner
authors.affiliation: Department of Dermatology, University Hospital Erlangen, Erlangen, Germany.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Erfurt-Berge
authors.affiliation: Department of Dermatology, Venereology, and Allergology, University Hospital Essen, Essen, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Dissemond
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000453:epidemiology*; D002648:Child; D015897:Comorbidity; D003953:Diagnosis-Related Groups / Q000706:statistics & numerical data; D005260:Female; D005858:Germany / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007871:Leg Ulcer / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008659:Metabolic Diseases / Q000175:diagnosis / Q000453:epidemiology*; D008875:Middle Aged; D009335:Necrobiosis Lipoidica / Q000175:diagnosis / Q000453:epidemiology*; D009765:Obesity / Q000175:diagnosis / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D017678:Sex Distribution; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000453:epidemiology*; D055815:Young Adult
keywords: DRG data; Necrobiosis lipoidica; cofactors; comorbidities; diabetes mellitus; leg ulcers