Abstract
Folie à deux is known by many other names such as double insanity, psychosis of association, induced delusional disorder, shared psychotic disorder and so on (total 18 names [1]). This phenomenon of a shared psychiatric disorder has been known for more than 150 years, but it still remains an elusive entity. This term was first introduced by Lasegue and Falret in 1873, who suggested that psychiatric disturbances under certain circumstances may transmit from one person to another [2]. The syndrome of folie à deux is uncommon, although some authors believe it to be more frequent than usually thought, especially when the patient is seen together with family members [3,4].
Usually the ‘primary’ individual, who first develops psychotic symptoms, can be distinguished from one or more ‘secondary’ individuals, in whom the symptoms are induced. The most common diagnosis in the primary individual is schizophrenia [5–7]. Among the secondary individuals, significant comorbidity was found in 62% [8]. Folie à deux is characterized by the presence of similar psychotic symptoms in two or more individuals who live together, so that delusions of the primary patient are adopted by the partner(s) [9]. The etiology of folie à deux is a controversial topic. The relationship between the psychopathology exhibited by the dominant partner and that shown by the submissive one remains unclear. The secondary individual may adopt untrue beliefs as a result of an over-dependent relationship with a deluded person [4,10,11].
Modern etiological theories attempt to fit the phenomena of folie à deux into a Procrustean bed, emphasizing in particular the contribution of schizophrenic pathology to the development of the condition. Hundreds of cases have been reported in the literature with psychotic symptoms [1,6,7].
However, to the best of our knowledge, there have been few reports of this phenomenon without evidence of psychotic symptomatology [12–14]. A case of shared obsessive–compulsive disorder (OCD) has been reported earlier in a couple [13] and more recently in two sisters [14]. We present a third case of induced OCD, which manifested in a couple.
History
Mr A was referred to our consultation service by his physician because of worsening obsessive–compulsive symptoms over the preceding 12 months. Mr A is a 32 year old married man with two children. He is an ultra-orthodox Jew and works as a cleaner. He regularly studies Jewish religious texts.
As a child, Mr A would try and avoid stepping on lines between paving stones on the footpath and would become upset if he happened to do so. He had not presented for psychological or psychiatric treatment in the past. He described himself as a sensitive child who completed 13 years of schooling successfully.
He married at the age of 21 years to an ultra-orthodox woman. She has been operating a home based crèche for the last several years. For many years Mr A experienced obsessive symptoms. He had excessive concerns about his wife's menstrual purity and even abstained from sexual relations because of these concerns.
Two years prior to his presentation, he experienced more distressing obsessional thoughts of religious guilt regarding theft and damaging the belongings of others. Twelve months prior to his referral he developed disabling compulsions to donate money to beggars on the street and to charity, resulting in him becoming anxious about leaving his house.
Mr A also suffered from compulsions to distribute sweets to the children who attended his wife's crèche. He also became scrupulous about the manner in which his wife recorded her work hours. He even took it upon himself to record her hours of work and deducted time out of concern that she would otherwise be ‘stealing’ from her clients. As a result, the couple suffered financial difficulties. Mr A understood that these compulsions were excessive and attempted to resist them unsuccessfully. He became increasingly distressed and experienced difficulty functioning in his social and occupational activities.
Mrs A, aged 30, presented to our service a few weeks after her husband's presentation on her own initiative, with similar complaints of compulsions over the last six months.
Her parents divorced when she was 10. She attended a boarding school between the ages of 14 and 17 and completed 12 years of schooling. She recalls few friendships as a child, and was easily hurt by criticism.
As an adult, Mrs A has few social contacts and leads an isolated and housebound lifestyle. Mrs A manifests a passive and dependent role in the marital relationship. She leaves her husband to take responsibility for housekeeping activities such as shopping, cleaning and day-to-day affairs. He also makes decisions regarding their children's schooling. She rarely takes initiative without consulting her husband. However, she does take responsibility regarding her private crèche. She regularly attends bible classes and takes her children to the local park. Mrs A denied a history of obsessive–compulsive symptoms prior to her marriage or a family history of mental illness.
She also experienced obsessional thoughts and compulsions to give charity to beggars on the street and sweets to children attending her crèche. She became scrupulous about the record of her work hours. These phenomena appeared six months after her husband began to manifest the same symptoms. The severity of Mrs A's symptoms was directly related to the severity of her husband's symptoms. When the couple was involved in a shared activity such as supervising the children in her crèche, one partner would encourage the other to carry out a compulsive behaviour such as giving more sweets to a child.
Mental status
Mr and Mrs A were seen individually and also as a couple. Both partners presented as appropriately dressed in ultra orthodox garb and cooperated throughout the interview.
Mr A's mood was anxious while describing his obsessions and compulsions. His affect was appropriate. He related positively to the interviewer and appeared interested to understand the nature of his difficulty and how to overcome his compulsions through pharmacological treatment. His intelligence appeared normal. He made no mention of his wife's compulsive behaviour. There was no evidence of delusions, hallucinations or thought disorder.
Mrs A's mood was lowered while describing her obsessions and compulsions. Her affect was appropriate. She related warmly during the interview and demonstrated spontaneity and initiative in her conversation. Her intelligence appeared normal and she demonstrated an ability to describe her emotional difficulties throughout the interview. She was able to recognize that her compulsions developed following similar behaviours in her husband. There was no evidence of psychotic symptoms or mood disorder.
Mr and Mrs A demonstrated appropriate insight into the ego dystonic nature of their obsessive–compulsive symptoms and were interested in receiving treatment. When seen together, both Mr and Mrs A showed a mutual positive regard for each other: Mr A presented as a supportive spouse. They both identified that Mr A's symptoms led to the development of similar symptoms in Mrs A.
Treatment
Mr A was only interested in pharmacological treatment. He received citalopram 60 mg/day after a titration period of 8 weeks. Clonazepam 1.5 mg/day was initiated and stopped after several weeks of treatment because of clinical improvement. Mrs A preferred not to receive pharmacological treatment since she was pregnant. Neither spouse was interested in psychotherapeutic treatment.
Progress
On the initial pre-treatment Yale-Brown Obsessive Compulsive Scale (Y-BOCS) severity rating [15], Mr A scored 32 (extreme severity) before treatment (obsession subtotal: 16, compulsion subtotal: 16) which decreased 4 months after treatment to a score of 5, subclinical severity (obsession subtotal: 5, compulsion subtotal: 0). On the Clinical Global Impression Scale [16], the Severity of Illness score was 6 (severely ill) before treatment and the Global Improvement score was 1 (very much improved) after 4 months of treatment. This improvement has continued up till today, 3 years later.
On the initial Y-BOCS severity rating Mrs A scored 22, moderate severity (obsession subtotal: 12, compulsion subtotal: 10). This score decreased to 1, subclinical severity (obsession subtotal: 1, compulsion subtotal: 0) 3 months later, without treatment and remains stable 3 years later. On the initial Clinical Global Impression Scale, the Severity of Illness score was 5 (markedly ill) and the Global Improvement Score was 1 (very much improved).
The couple did not attend regular follow-up. However, they were willing to be reviewed by telephone. They described a gradual improvement in their compulsions, and were able to support one another in resisting these symptoms.
Both Mr and Mrs A used the same expression to describe their condition: ‘I was confused in the past. I now feel 90% better.’
Currently, Mr A is taking 60 mg citalopram per day. In the past he has tried stopping the medication for short periods and on each occasion his OCD symptoms became worse. Whilst taking citalopram he no longer suffers from compulsions, and only complains of mild, intermittent symptoms of obsessions relating to giving charity.
More than 3 years after the initial consultation, Mrs A remains symptom-free without medication. She resolved that she would not be influenced by her husband's obsessions.
Discussion
Folie à deux is defined as delusional (shared psychotic disorder [17]) and according to modern definitions relates to schizophrenia. Some authors suggest that folie à deux may also involve non-psychotic pathology [4,10,11,13,14]. While folie à deux is uncommon, shared obsessive–compulsive disorder is even more uncommon. However, some authors suggest that the true population prevalence of folie à deux is difficult to assess, as under-diagnosis and underreporting are likely to be considerable [18,19].
The mechanism by which induction of delusions in the secondary person takes place is poorly understood. Various theories have been suggested to explain the phenomenon [1], including the original theories of environment and susceptibility, psychodynamic explanations, theories based on psychopathology, developmental considerations, stress vulnerability theories, and explanations based on family therapy perspectives. To date, no single theory has been able to fully explain the etiology and pathogenesis of induced delusional disorder.
Our case illustrates that the psychopathology of shared psychiatric disorder may be non-psychotic in nature. In our case, neither spouse demonstrated delusional material. An important aspect of the treatment of shared psychotic disorder is the separation of the ‘primary’ and ‘secondary’ person both physically and psychologically [6]. One could argue that Mrs A's self referral indicated her motivation developing this process of separating from her husband's illness.
In OCD it is very common for the rituals of a sufferer to involve significant others, either directly (making them wash) or indirectly (asking them repetitively for reassurance: ‘am I clean?’, ‘did I give to that beggar?’) and by colluding in avoidant behaviours. In our case, Mrs A demonstrated ongoing obsessions and compulsions for a period of more than 6 months. Moreover, Mrs A suffered from compulsions independently of her husband's presence. This pattern would suggest a shared disorder rather than merely the response of a significant other to a person's OCD.
The two previous case reports of shared OCD [14,15] suggested that this phenomenon of shared OCD could represent the continuum between obsessions and delusions. In contradistinction to this view, we suggest that shared OCD may represent a different diagnostic entity. Both Mr and Mrs A demonstrated insight into the shared nature of their OCD symptoms and sought help. In our experience, most persons suffering from shared psychotic disorder receive treatment only after the intervention of external agencies.
Our case is difficult to classify according to the current diagnostic criteria. We suggest broadening the concept of shared psychiatric disorder in order to include both psychotic and non-psychotic forms of this illness. We propose that the category of shared non-psychotic disorder may include other psychiatric disorders such as ‘shared OCD’ and possibly ‘shared depressive disorder’ or ‘shared anxiety disorder’.
Further research is required in order to determine whether this revised classification has a clinical basis. If so, this disorder should be considered as a separate diagnostic entity in current psychiatric diagnostic classification systems (DSM and ICD). This revision would encourage researchers and clinicians to develop more controlled studies in order to better understand the psychopathology and mechanisms of psychotic and non-psychotic shared disorders in psychiatry. Important treatment implications may result from such an understanding.
Footnotes
Acknowledgements
We thank Cornelius Gropp and Elie Lefkifker for their helpful comments.