Obsessive-Compulsive Disorder: the experience in Turin began in the early 90s…

Since the early 90s, our director and senior teacher Luigi Ravizza had stimulated the interest of his entire research group on anxiety disorders, which at that time included obsessive-compulsive disorder. The research group was engaged in two lines of study and research: biological and clinical.

Paola Rocca began working on biological correlates and in particular on peripheral benzodiazepine receptors. Peripheral benzodiazepine receptors (pBDZr) were analyzed in lymphocyte membranes from patients with anxiety disorders (generalized anxiety disorder (GAD), panic disorder (PD), and obsessive-compulsive disorder (OCD), and compared with patients with other mental disorders and healthy controls, by the specific binding of 3H-PK11195 ¹. The number of binding sites (Bmax) was significantly decreased in groups with both GAD and OCD as compared with age-matched controls, by 45% and 25%, respectively, whereas the binding affinity (Kd) was the same in all disorder and control groups. Conversely, no changes in binding capacity was observed in the other disorder groups and particularly in the one with PD. The abnormality in pBDZr observed in patients with GAD was restored to a normal value after long-term treatment with 2’-chloro-N-desmethyldiazepam, which also coincided with their recovery from anxiety. These data strongly suggested the heterogeneity in anxiety disorders related to different biological mechanisms and that lymphocyte pBDZr might be useful in demonstrating these differences.

A few years later, attention to peripheral biological correlates was deepened in OCD by Paola Rocca and her research group suggesting that modulation of pBDZr gene expression might also delineate a clinical heterogeneity in OCD ². The relative content of peripheral benzodiazepine receptor (pBDZr) mRNA was examined by reverse transcriptase-polymerase chain reaction in lymphocytes of obsessive-compulsive disorder (OCD) patients, according to their clinical course of illness. pBDZr mRNA significantly decreased only in chronic OCD patients as compared to controls, whereas no significant changes were observed in episodic OCD patients. We suggest that modulation of pBDZr gene expression might delineate a clinical heterogeneity in OCD.

The line of clinical and psychopathological research on OCD was started by Giuseppe Maina and Filippo Bogetto. At that time, OCD was already considered by the Turin research group as a separate entity from anxiety disorders, although the disorder remained included among anxiety disorders until the publication of DSM5 in 2013.

A clinical observation that our group often discussed in the early 90s and that emerged from the follow-up of many patients led to our first study hypothesis: are there clinical pictures of OCD with an episodic course of the illness? Until then, the literature mainly described OCD as a chronic disorder. In DSM-IIIR (1987), the clinical course of OCD was described as chronic with fluctuations. Our hypothesis that we were working on since 1994 led to one of our first international publications: we published our preliminary data on the existence of episodic OCD, suggesting that this subgroup may be a distinct subtype within the whole group of obsessive-compulsive patients with significant differences in sex ratio, age at onset of the disorder, illness duration, type of symptoms, and familial history ³. 

After that first publication, the Turin research group on OCD continued its study and research in various directions:

Epidemiological ⁴, family studies ⁵ and studies on the onset of the disorder ^6,7,8;

Studies on comorbidities and on the risk of suicide ^{9, 10};

Studies on family accommodation ¹¹;

Studies on treatment: resistance to medications and combined treatments (CBT added to drug therapy) ^12,13,14.

The scientific production on the clinic and therapy of OCD has led to over 100 articles published in international journals, and we are also very grateful to Professors Ravizza and Bogetto for this. The contribution has been very broad from many colleagues from Turin: Umberto Albert, Giulio Barzega, Silvio Bellino, and Gianluca Rosso, just to name a few. 

Collaboration in research projects had extended from the beginning to other Italian and international research groups. Among the first are the Pisan school of Professors Giovanni Cassano and Donatella Marazziti, the Milanese school of Professors Smeraldi and Bellodi, and the Florentine school of Professor Stefano Pallanti. The international research groups were those of Professor Joseph Zohar (Israel), Professor Eric Hollander (USA), and Professor Naomi Fineberg (UK).

The formalization of these collaborations occurred with the foundation in May 1996 of the Association “Gruppo Italiano Disturbi Ossessivo-Compulsivi (GIDOC)” (founding members: Prof. G.B. Cassano, D. Marazziti, S. Pallanti, G. Maina, L. Ravizza) which was affiliated with the “International College of OCD. WPA Section on OCD”.

Finally, we would like to point out a monograph to which Professor Ravizza was very attached: ‘Il Disturbo Ossessivo-Compulsivo’, published by Masson in 1997 ¹².

In Turin studies on OCD continue…