Recovery From Schizophrenia: Psychiatry And Political Economy

THE POLITICAL ECONOMY OF SCHIZOPHRENIA 197In carrying out such a survey the researchers may plan to interview every personin the community or, to save time and expense, they may evaluate only thosepeople who are identified by key informants (such as tribal chiefs or generalpractitioners) as possibly suffering from the illness. An approximation toprevalence can also be calculated from the number of cases in treatment at hospitalsand clinics during a given period. Again this method, which assumes that virtuallyall cases of a disorder are in treatment, is inapplicable to the study of schizophreniain most of the Third World. Prevalence data for schizophrenia vary more widelythan incidence data from 0.3 to 5 per 1,000 of the population in studies of theUnited States, from 2 to 17 per 1,000 in Europe, from 2 to 18 per 1,000 in Japanand from 0.4 to 7 per 1,000 in the developing world. 5While we may use incidence data to draw conclusions about what causes theappearance of an illness, strictly speaking, we should not use prevalence data inthe same way. Prevalence figures for schizophrenia are the product of threeprocesses—the rate of appearance of the illness (the incidence), the death rate ofpeople with schizophrenia (which is greater in the Third World), and (except inthe case of lifetime prevalence) the rate of recovery.A problem with comparing different studies of the occurrence ofschizophrenia, especially for Third World peoples, is that to draw an accuratepicture it is necessary to know the age distribution of each population. Where alarge proportion of the population is below age 15, for example, and not atsignificant risk of developing schizophrenia, one must expect a spuriously lowprevalence of the illness. This source of error would be particularly evident in theThird World, where birth rates tend to be higher and life expectancy shorter thanin the West, or in assessing changes in the same culture over a long period oftime. In order to correct for this effect it is necessary to calculate a standardized,age-corrected prevalence figure.Clearly, there are difficulties associated with assessing changes in the frequencyof an illness over time or comparing rates between different parts of the world—incidence versus prevalence, point prevalence versus lifetime prevalence,community survey versus treatment statistics, narrow versus broad diagnosis andage-correction differences. It is not surprising that the statistics vary substantiallyand it is clear that we have to be cautious in interpreting the available data.Bearing this point in mind, we may return to the issue of variations in theoccurrence of schizophrenia over time and what they tell us about links betweenthe illness and society.WAS SCHIZOPHRENIA RARE BEFORE THEEIGHTEENTH CENTURY?Is schizophrenia, like death and taxes, an unavoidable part of human existence?Psychiatrist Fuller Torrey argues that it is not; he suggests that schizophrenia maynot have existed prior to the eighteenth century. 6 Several other authors disagree,however. 7 There is evidence, for example, that the inhabitants of ancient India and