Early intervention in psychosis: Future or fad?
CrossCurrents
The Last Word
Dr. Richard Warner
Early intervention in psychosis has generated much interest and optimism. But is this enthusiasm backed by satisfactory research
evidence? To answer this question we have to understand that “early intervention” refers to two different approaches – intervention
before and after the onset of psychosis. The problems, risks and potential benefits are quite different for each.
The belief that early intervention in fully evident psychosis will lead to better outcomes is based on data showing that the
duration of untreated psychosis (DUP) is associated with worse course and outcome. It is unlikely, however, that this association
is a direct effect of prolonged psychosis. A substantial proportion of those who present with a first episode of a schizophrenia-like
condition will recover rapidly, and samples of patients with a shorter duration of illness will include more good-prognosis
cases and will have better overall outcome. In fact, the association between DUP and poor outcome only holds true for cases
of recent onset, and the studies that do not include recent cases fail to show an association between DUP and outcome. Some
researchers have gone so far as to suggest that untreated psychosis may be toxic to brain function, but this appears unlikely,
since nearly all recent studies demonstrate no association between DUP and cortical atrophy or decreased cognitive functioning.
Claims for the benefits of early intervention go back two centuries. Nineteenth-century madhouse proprietors claimed that
the deranged were more easily restored to health if they were admitted early. The British Metropolitan Commissioners of Lunacy
cited tables demonstrating that cures were more likely when patients are admitted within three months of onset. Their enthusiasm
led to the Lunatics Acts of 1845 and the construction of a national network of county asylums. We look back now with a sense
of superiority on the self-promotion of the early asylum proprietors and the lack of scientific rigour, but the data currently
being offered in support of early intervention suffer from the same weaknesses.
Over-enthusiastic early intervention can be dangerous for those experiencing an episode of good-prognosis psychosis, which
is destined to go into early remission without drug treatment. A World Health Organization study found that 15 per cent of
those presenting with a schizophrenia-like illness in the developed world recovered within four months and stayed well for
two years. The Soteria projects in California and Berne, Switzerland, and a multi-centre study in Finland demonstrated that
medication is not essential for good outcome. Medicating at the earliest appearance of symptoms, without thought for the natural
history of the condition, may lock the person experiencing a brief psychosis into a long-term career as a psychiatric patient.
As for the claim that we can prevent psychosis by intervening before the illness has become fully evident, this effort requires
effective screening to detect those at risk. Patrick McGorry and colleagues at the PACE clinic in Melbourne, Australia, the
best-known centre for this work, report that their screening instrument is capable of 80 per cent accuracy in their clinic.
But the instrument is not that accurate in routine use. In the PACE sample, 35 per cent developed psychosis within one year.
Probability theory tells us that if the same instrument were used to screen a general population sample with the usual rate
of occurrence of psychosis of around one per cent, it would be correct only seven per cent of the time, and if it were applied
to a clinic population where the risk of developing psychosis in a year was, say, five per cent, the instrument would be correct
only 30 per cent of the time. In fact, in another Australian clinic, the PACE instrument only achieved nine per cent accuracy.
False- positive rates of the order of 70 to 90 per cent are clearly unrealistic for intervening with medication or other forms
of treatment.
McGorry speculates that a variety of interventions may be effective in preventing schizophrenia in high-risk cases. The suggested
approaches include antipsychotic medication, family intervention and “lifestyle restructure.” Given the expected number of
false positives, the potential for harm is significant. Should we prescribe antipsychotic medications for someone with no
positive symptoms? How much harm will be done to people who will never develop the illness to tell them they are at risk for
schizophrenia, need treatment and must adjust their life goals? In a pre-illness treatment study conducted by PACE, participants
were assigned to preventive treatment with cognitive therapy and the antipsychotic drug risperidone or to a control group
with supportive psychotherapy. Only three of 31 preventive treatment participants developed psychosis after six months compared
to 10 of the 28 in the control group. Thus, the onset of psychosis may have been delayed in about seven of the experimental
group. We have to set this against the fact that 21 participants in the experimental group were told they were at risk for
schizophrenia when they were not, and took risperidone unnecessarily. How does one decide, moreover, how long the 28 symptom-free
participants taking risperidone should continue on medication? For three-quarters of the group, the medication is unnecessary,
but one doesn’t know who those individuals are.
Prevention specialists ask a series of questions to determine if a screening program will do more harm than good. Does the
burden of disease warrant screening? Is there an effective preventive intervention? Is there a good screening test? Will the
program reach those who would benefit? Can the healthcare system handle the screening? Will the screen-positive individuals
comply with the intervention? In the case of schizophrenia, the answer to the first question is a resounding “yes,” but to
the remainder, the answers are “no” or, at best, “doubtfully.” Looked at in this light, pre-illness screening for schizophrenia
is unlikely to succeed. Nor is early intervention in fully evident psychosis likely to yield the hoped-for benefits.
Richard Warner, MB, DPM, is director of Colorado Recovery in Boulder, Colorado, and professor of psychiatry at the University
of Colorado.
Editorials do not necessarily reflect the views of CAMH. We welcome submissions from our readers. For information, contact
the Editor, CrossCurrents, 33 Russell St., Toronto, Ontario M5S 2S1, tel 416 595-6714, e-mail hema_zbogar@camh.net
Centre for Addiction
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