title: Late-onset obsessive-compulsive disorder: risk factors and correlates.
abstract: BACKGROUND
  While a great amount of attention has been paid to early-onset obsessive-compulsive disorder (OCD), there is a dearth of studies on patients showing OCD for the first time at later stages of life. In this study, we aimed at determining possible risk factors/correlates for OCD onset at or after age 40, here termed late-onset OCD.
  
  
  METHODS
  A series of models including several potential variables associated with late onset OCD were tested using a monolayer neural network. To this regard, data from the Brazilian Research Consortium of Obsessive-Compulsive Spectrum Disorders (CTOC) (n = 1001) was employed. For the purposes of this study, we considered a diagnosis of late onset OCD to be present whenever distress and interference associated with OCD symptoms emerged at or after age 40. Different nested models were compared through the Akaike Criteria keeping the variables with p value ≤0.05.
  
  
  RESULTS
  Late-onset OCD occurred in 8.6% of the sample. A model including female sex, a history of chronic (>10 years) subclinical obsessive-compulsive symptoms, the co-occurrence of posttraumatic stress disorder (PTSD) after age 40, and a history of recent pregnancy in self or significant others was able to explain a sizeable proportion of late-onset OCD. The general performance of this model, represented by the Maximum Likelihood R2, was 29.4%.
  
  
  CONCLUSIONS
  Our results suggest that late-onset OCD is more likely to occur in females, in individuals with long periods of subclinical obsessive-compulsive symptoms, and in association with a major traumatic event occurring after age 40 and a history of recent pregnancy in self or in significant others.
authors.affiliation: Anxiety and Depression Research Program, Institute of Psychiatry, Federal University of Rio de Janeiro, Brazil; D'Or Institute for Research and Education, Brazil. Electronic address: ilanafryd@yahoo.com.br.
authors.forename: Ilana
authors.initials: I
authors.lastname: Frydman
authors.affiliation: D'Or Institute for Research and Education, Brazil.
authors.forename: Pedro E
authors.initials: PE
authors.lastname: do Brasil
authors.affiliation: Department of Neurology, Psychology and Psychiatry, Botucatu Medical School, Universidade Estadual Paulista, Brazil.
authors.forename: Albina R
authors.initials: AR
authors.lastname: Torres
authors.affiliation: Department of Psychiatry, University of São Paulo Medical School, Brazil.
authors.forename: Roseli G
authors.initials: RG
authors.lastname: Shavitt
authors.affiliation: Department of Psychiatry, Health Sciences Federal University of Porto Alegre, Brazil.
authors.forename: Ygor A
authors.initials: YA
authors.lastname: Ferrão
authors.affiliation: Department of Psychiatry, Federal University of São Paulo, Brazil.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Rosário
authors.affiliation: Department of Psychiatry, University of São Paulo Medical School, Brazil.
authors.forename: Euripedes C
authors.initials: EC
authors.lastname: Miguel
authors.affiliation: Anxiety and Depression Research Program, Institute of Psychiatry, Federal University of Rio de Janeiro, Brazil; Department of Psychiatry and Mental Health, Institute of Community Health, Fluminense Federal University, Brazil; D'Or Institute for Research and Education, Brazil.
authors.forename: Leonardo F
authors.initials: LF
authors.lastname: Fontenelle
mesh_terms: D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D001938:Brazil / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis* / Q000453:epidemiology*; D011247:Pregnancy; D011569:Psychiatric Status Rating Scales; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
keywords: Clinical course; Late-onset; Obsessive-compulsive disorder; Onset; Phenotype