title: Risk factors for recurrence after successful treatment of warts: the role of smoking habits.
abstract: BACKGROUND
  Several therapies have been proposed for cutaneous warts without results concerning factors affecting recurrences.
  
  
  OBJECTIVE
  To determine the importance of individual characteristics and different therapy modalities in the occurrence of relapses.
  
  
  METHODS
  Observational prospective cohort study including 199 patients affected by multiple plantar warts treated as follows: 49 with keratolytics, 50 with CO2laser, 50 with pulsed dye laser (PDL) and 50 with cryotherapy. Personal data were evaluated through a questionnaire, and treatment information was collected. A Cox regression analysis was performed to identify independent factors for relapse occurrence.
  
  
  RESULTS
  Of patients, 57.8% showed a persistent clearance of warts after treatment with a higher recurrence-free interval when treated with PDL. Accordingly, the risk of recurrence was increased with CO2laser [hazard ratio (HR) 2.92, 95% confidence interval (CI) 1.49-5.74] and keratolytic treatment (HR 3.23, 95% CI 1.60-6.54), as compared to PDL. Furthermore, the multivariate analysis highlighted a higher risk of recurrence in patients between 26 and 35 years (HR 1.88, 95% CI 1.03-3.45), older than 35 (HR 2.23, 95% CI 1.23-4.07) and smokers (HR 4.90, 95% CI 3.09-7.78).
  
  
  CONCLUSIONS
  Pulsed dye laser is characterized by the lowest rate of recurrence. Furthermore, our study highlights that the risk of warts relapse is 5-fold higher in smokers compared to non-smokers, revealing the importance of the effects of smoking on inflammation and immune response.
authors.affiliation: Istituto di Chirurgia e Laserchirurgia in Dermatologia (I.C.L.I.D.), Milan, Italy.|Italian High Tech Network in Dermatological Sciences, Milan, Italy.
authors.forename: P L
authors.initials: PL
authors.lastname: Bencini
authors.affiliation: Istituto di Chirurgia e Laserchirurgia in Dermatologia (I.C.L.I.D.), Milan, Italy.|Dermatology Unit, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Guida
authors.affiliation: Centro Studi GISED, Fondazione per la Ricerca Ospedale Maggiore, Bergamo, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Cazzaniga
authors.affiliation: Dermatology Unit, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Pellacani
authors.affiliation: Istituto di Chirurgia e Laserchirurgia in Dermatologia (I.C.L.I.D.), Milan, Italy.|Italian High Tech Network in Dermatological Sciences, Milan, Italy.
authors.forename: M G
authors.initials: MG
authors.lastname: Galimberti
authors.affiliation: Medical School, Sacco Hospital, University of Milan, Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Bencini
authors.affiliation: Italian High Tech Network in Dermatological Sciences, Milan, Italy.|Centro Studi GISED, Fondazione per la Ricerca Ospedale Maggiore, Bergamo, Italy.|Dermatology Unit, Azienda Ospedaliera Papa Giovanni XXIII, Bergamo, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Naldi
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D017679:Cryotherapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007641:Keratolytic Agents / Q000627:therapeutic use*; D054025:Lasers, Dye / Q000627:therapeutic use*; D054020:Lasers, Gas / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D014860:Warts / Q000628:therapy*; D055815:Young Adult
chemical_list: D007641:Keratolytic Agents