Obsessive-compulsive disorders : Personality traits and disorders, autistic traits and biochemical findings

Abstract: Background: Obsessive-compulsive disorder (OCD) is a common disabling mental disorder.Personality disorders are frequent in OCD. Asperger syndrome and high-functioning autism share similarities with obsessive-compulsive and schizoid personality disorders and may be referred to as "odd" personality traits. Also compulsions are common in autism. The present study aims at investigating personality disorders and dimensions in OCD and their relationship to autistic traits Sixty-four subjects suffering from OCD participated. The Karolinska Scales of Personality (KSP), the Temperament and Character Inventory (TCI), self-report questionnaires for personality disorders and an instrument to identify autistic traits were used. Nicotine use and its relation to personality traits were investigated in 193 subjects with OCD. In addition, we looked for serotonergic response predictors in, therapy with SRIs, by investigating serotonin levels in whole blood repeatedly during treatment with SRIs in 36 patients with OCD. Finally,one patient that needed high dose treatmentwith SRIs is presented.Results: In 61% of the 64 subjects with OCD, personality disorders were identified. More-over, subjects with OCD had significantly higher scores in KSP scales measuring Anxiety, Muscular tension, Psychasthenia, Indirect aggression, Irritability, Suspicion and Guilt, whereas Socialization and Social desirability were lower. The TCI scale measuring Harm avoidance was higher among subjects with OCD and Self-directedness and Cooperativeness were lower. In addition we found obvious autistic traits in 20 % of the subjects. Subjects with autistic traits fulfilled significantly more personality disorder criteria. In addition, subjects with autistic traits scored significantly higher on KSP scales measuring Muscular tension, Psychasthenia and Inhibition of aggression whereas Socialization was lower as compared to OCD subjects without autistic traits. However, subjects with most conspicuous autistic traits lacked insight, and identified less of those traits in themselves. Smoking was rare among subjects with OCD,especially among those with an obsessive-compulsive personality disorder. Smokers with OCD did not differ from the normal population as regard to personality disorders and traits, and none had autistic traits. Autistic traits predicted non-response to SRI treatment. Those subjects who responded to SRI treatmenthad significantly less reduction of whole-blood serotonin after one week as compared to non-responders. Occasionally, high doses of SRIs may be needed.Conclusions: In OCD, autistic traits are common whereas smoking is race. Subjects with OCD and autistic traits may be identical to those OCD subjects often referred to as "odd" or schizotypal. OCD with autistic traits is suggested to constitute a distinct phenotype within the neuropsychiatric spectrum. A possible response predictor in pharmacotherapy of OCD is suggested.