Social and communication difficulties and obsessive-compulsive disorder

Area of Science:

• Psychiatry
• Genetics
• Developmental Psychology

Background:

• Obsessive-compulsive disorder (OCD) and pervasive developmental disorder (PDD) share phenomenological features, including abnormal social and communication behaviors (pragmatic behaviors).
• The broader autism phenotype (BAP) also encompasses pragmatic behaviors, linking PDD and OCD.
• The association between pragmatic behaviors and OCD, and its potential to define a familial subtype, requires further investigation.

Purpose of the Study:

• To investigate the association between abnormal pragmatic behaviors and OCD.
• To determine if this association identifies a familial subtype of OCD.
• To explore the potential link between pragmatic behaviors in OCD families and PDD/BAP.

Main Methods:

• Utilized data from the Johns Hopkins OCD Family Study, including 80 OCD case probands and 73 control probands.
• Conducted interviews with probands and first-degree relatives using standardized diagnostic instruments.
• Administered the Pragmatic Rating Scale (PRS) to assess pragmatic behaviors in 395 subjects.

Main Results:

• A significantly greater prevalence of high PRS scores (indicating abnormal pragmatic behaviors) was observed in OCD case probands and their relatives (5%) compared to controls (0.5%, p = 0.011).
• The PRS was completed on 395 subjects, with 3% (n = 11) scoring above the threshold.
• OCD prevalence was significantly higher in relatives of OCD cases who had a family member with a high PRS score (p < 0.001).

Conclusions:

• The presence of social and communication difficulties within OCD families suggests a distinct familial subtype of OCD.
• This familial subtype may be associated with PDD and/or BAP.
• The study's findings were based on PRS assessment of pragmatic behaviors in subjects with OCD.