The groundbreaking and highly contentious theory, co-presented by New Zealand clinical psychologist Dr John Read, has been described as "an earthquake" that will radically change the psychiatric profession.
Clinical psychologist and writer Dr Oliver James commented: "The psychiatric establishment is about to experience an earthquake that will shake its intellectual foundations [and] may trigger a landslide."
Mr Hammersley, Programme Director for the COPE (Collaboration of Psychosocial Education) Initiative at the School of Nursing Midwifery and Social Work, said: "We are not returning to the 1960s and making the mistake of blaming families, but professionals have to realize that child abuse was a reality for large numbers of adult sufferers of psychosis."
He added: "We work very closely in collaboration with the Hearing Voices Network, that is with the people who hear voices in their head. The experience of hearing voices is consistently associated with childhood trauma regardless of diagnosis or genetic pedigree."
Dr Read said: "I hope we soon see a more balanced and evidence-based approach to schizophrenia and people using mental health services being asked what has happened to them and being given help instead of stigmatizing labels and mood-altering drugs."
Hammersley and Read argue that two-thirds of people diagnosed as schizophrenic have suffered physical or sexual abuse and thus it is shown to be a major, if not the major, cause of the illness. With a proven connection between the symptoms of post-traumatic stress disorder and schizophrenia, they say, many schizophrenic symptoms are actually caused by trauma.
Their evidence includes 40 studies, which revealed childhood or adulthood sexual or physical abuse in the history of the majority of psychiatric patients and a review of 13 studies of schizophrenics found abuse rates from a low of 51% to a high of 97%. Psychiatric patients who report abuse are much more likely to experience hallucinations – flashbacks which have become part of the schizophrenic experience and hallucinations or voices that bully them as their abuser did thus causing paranoia and a mistrust of people close to them.
They admit not all schizophrenics suffered trauma and not all abused people develop the illness, but believe less traumatic childhood maltreatment, rather than actual abuse, may be an important difference. In their review of the 33,648 studies conducted into the causes of schizophrenia between 1961 and 2000, they found that less than 1% was spent on examining the impact of parental care. Still, they say, there have been enough studies to suggest negative or confusing early care may be an important addition to abuse as a cause.
Genes may still have a role to play but other evidence Hammersley and Read cite shows that genes alone do not cause the illness. A recent study compared 56 adoptees born to schizophrenic mothers with 96 adoptees whose biological parents did not have the illness. The families were observed extensively when the children were small and all the adoptees were assessed for psychiatric illness in adulthood. It was found that if there was a high genetic risk and it was combined with mystifying care during upbringing, the likelihood of developing schizophrenia was greater - genes alone did not cause the illness.
In addition a recent review revealed that, apart from for Alzheimer's, not a single gene has been shown to play a critical role in any mental illness, while sociological studies show that schizophrenia poor people are several times more likely than the rich to suffer schizophrenia and urban life increases the risk.
Finally, they argue, if patients believe their illness is an unchangeable genetic destiny and that it is a physical problem requiring a physical solution, they will readily accept a drug prescribed to them when in fact they require other therapy. Worse, those who buy the genetic fairytale are less likely to recover, and that parents who do so are less supportive of their offspring. They recommend that all patients be asked in detail about whether they have been abused, anti-psychotic drugs no longer be doled out automatically and psychological therapies offered more often.
Hammersley and Read will propose the motion 'Tears on my pillow, voices in my head: This house believes child abuse is a cause of schizophrenia' at a public debate at the Institute of Psychiatry in London on 14 June 2006. They will also be speaking at 15th ISPS Symposium for the Psychotherapy of Schizophrenia and other Psychoses in Madrid on the same day.
For more information or to arrange an interview with Paul Hammersley please contact Media Relations Officers Mikaela Sitford or Jo Nightingale on 0161 275 2111 or 8156.
John Read is available (New Zealand time difference) on +64 21 039 7168.
Editor's note:
For more information on the Institute of Psychiatry visit http://www.iop.kcl.ac.uk/
The University of Manchester The University of Manchester (www.manchester.ac.uk) is the largest higher education institution in the country with almost 36 000 students. Its Faculty of Medical & Human Sciences (www.mhs.manchester.ac.uk) is one of the largest faculties of clinical and health sciences in Europe, with a research income of over £37 million. The School of Nursing, Midwifery and Social Work enjoys national and international research acclaim, attracts considerable funding and publishes extensively in internationally renowned journals. It has three research groups which comprise a number of project and theme-based teams – acute care and rehabilitation, primary health care and mental health.
The University of Auckland is New Zealand's pre-eminent research-led University. Established in 1883, it has grown into an international centre of learning and academic excellence and is New Zealand's largest university. The Department of Psychology has teaching and research interests in social psychology, cognitive neuroscience, child development, learning, industrial/organisational psychology, speech language therapy/speech science, clinical, health psychology, and psychological and developmental disabilities.