Abstract

BACKGROUND:

The relationship between pervasive developmental disorder (PDD) and obsessive-compulsive disorder (OCD) has not been extensively studied despite having some phenomenological features in common. Abnormal social and communication behaviors (pragmatic behaviors) are key components of PDD and are also part of the broader autism phenotype (BAP). In this study we sought to establish if there is any association between the presence of abnormal pragmatic behaviors and OCD and whether this association delineates a familial subtype of OCD.

SAMPLING AND METHODS:

As part of the Johns Hopkins OCD Family Study, 80 OCD case probands were recruited and matched with 73 control probands. Probands and their first-degree relatives were interviewed using the Schedule for Affective Disorders and Schizophrenia-Lifetime Anxiety and other diagnostic instruments. A Pragmatic Rating Scale (PRS) to assess pragmatic behaviors was completed by the examiner.

RESULTS:

The PRS was completed on 395 subjects, of which 3% (n = 11) achieved a score of greater than 6. The prevalence of high PRS scores was significantly greater amongst case probands and relatives (5%) compared to control probands and relatives (0.5%, p = 0.011). In case relatives the prevalence of OCD was significantly higher in those relatives who had a family member with a high PRS score (p < 0.001).

CONCLUSIONS:

The presence of social and communication difficulties in members of OCD case families appears to identify a familial subtype of OCD that may be related to PDD and/or BAP. This study was limited to using the PRS to identify pragmatic behaviors in subjects with OCD.