title: Melasma and its association with different types of nevi in women: a case-control study.
abstract: BACKGROUND
  Very little is known about possible association of nevi and melasma. The study objective was to determine if there is an association between melasma and existence of different kinds of nevi.
  
  
  METHODS
  In a case-control study, 120 female melasma patients referred to dermatology clinic of Ardabil and 120 patients referred to other specialty clinics who lacked melasma were enrolled after matching for age. Number of different types of nevi including lentigines and melanocytic nevi were compared between case and control group patients. Data were entered into the computer and analyzed by SPSS 13 statistical software.
  
  
  RESULTS
  Mean number of lentigines was 25.5 in melasma group compared to 8 in control group(P < 0.01). Mean number of melanocytic nevi was 13.2 in cases compared to 2.8 in control group(P < 0.001). Multivariate analysis showed that existence of freckles, lentigines and more than three melanocytic nevi were positively related to developing melasma. The chance of melasma increased up to 23 times for patients having more than three melanocytic nevi. Congenital nevi were observed among 10% both in case and control groups. Campbell de morgan angiomas were seen among 26 patients(21.8%) in case group compared to 6 patients(5%) in control group.
  
  
  CONCLUSIONS
  Existence of lentigines and melanocytic nevi increases chance of having melasma.
authors.affiliation: Department of public health sciences, Karolinska Institute, Stockholm, Sweden. h.adallatkhah@arums.ac.ir
authors.forename: Hassan
authors.initials: H
authors.lastname: Adalatkhah
authors.forename: Homayoun
authors.initials: H
authors.lastname: Sadeghi-bazargani
authors.forename: Nayereh
authors.initials: N
authors.lastname: Amini-sani
authors.forename: Somayeh
authors.initials: S
authors.lastname: Zeynizadeh
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006391:Hemangioma / Q000150:complications*; D006801:Humans; D007492:Iran / Q000453:epidemiology; D016015:Logistic Models; D008548:Melanosis / Q000150:complications* / Q000453:epidemiology; D015999:Multivariate Analysis; D009508:Nevus, Pigmented / Q000150:complications*; D015995:Prevalence; D012307:Risk Factors; D012878:Skin Neoplasms / Q000150:complications*; D011795:Surveys and Questionnaires