Why prevalence of schizophrenia among immigrants is so high.
Immigrants are more often than natives diagnosed with schizophrenia. Afro-Carribeans in England, Inuits in Denmark and Moroccans in the Netherlands are among the most likely to become schizophrenic, according to a Dutch newspaper article. New research however has indicated that standardized test may overdiagnose immigrants due to cultural misinterpretation.
What is schizophrenia?
Schizophrenia is a chronic mental disorder in which a person suffers, among other things, from delusions and hallucinations. One common example of hallucination is hearing voices inside one’s own head. Although 10 to 20 percent of people has the hereditary predisposition for schizophrenia, its manifestation is not as common.
Specifically stressful happenings in one’s life are known to spark schizophrenia. One of the common factors is held to be migration. In fact, the likeliness for second-generation Moroccan immigrant men in the Netherlands to be diagnosed with schizophrenia is seven times higher than that of Dutch men.
An immigrant’s disease?
One explanation for this is that immigrants may more often experience feelings of humiliation, which is known to affect the production of dopamine in the brain, which is also linked to schizophrenia. Schizophrenic people in fact produce an abundance of dopamine.
Another reason could be the standard questionnaires that are being used to diagnose patients for schizophrenia. Most doctors prefer to not know the cultural or ethnic background of its patient, in order to diagnose as unpresumptious as possible. The aim to be culturally unbiased however, may actually cause patients to be wrongly diagnosed with schizophrenia.
Researcher Tekleh Zandi suspected that immigrants may be overdiagnosed as schizophrenic as a result of different interpretations of the disease’s symptoms. Specifically hearing voices as well as experiencing dissaociation may actually be more susceptible to cultural interpretation than one may think at first.
Many cultures in fact consider it to be a normal, non-pathological experience to hear voices, such as those of elders, inside one’s head. Moroccan parents are often concerned with sick children being at risk of becoming possessed by demons. They therefore often ask their children if they hear voices, which may cause adults to still associate being physically or mentally sick with hearing voices.
Dissociative phenomena, another common symptom of schizophrenia in which a person feels removed from their own body, may also be subject to cultural interpretation. To go into a state of trance, for example, is a religious phenomenon which is not considered as pathological by many cultures.
In the study two tests were used; the standard instrument used for diagnosing schizophrenia as well as a moderated, culturally sensitive version of the normal test. 26 Moroccan and 26 Dutch patients were subjected to both tests twice, with a time span of 30 months in between.
The diagnostic stability between the first and second standard test was very high for Dutch patients (92%), while it was particularly low for Moroccan patients (27%). That Morrocan patients were often ‘cured’ after 30 months is odd, considering the usually chronic character of schizophrenia. The moderated version of the test on the other hand has a similar diagnostic consistency for both Dutch (81%) and Morrocan (85%) patients.
Another research was performed in a Dutch hospital, in which Morrocan immigrants and Dutch patients with a possible psychotic disorder were tested with both the regular and the culturally sensitive instrument. Whilst the regular test diagnosed 65% of Morrocan and 51% of native Dutch patients as schizophrenic, the culturally sensitive adapted test diagnosed schizophrenia among 59% of Dutch and among 15% of Moroccan patients.
This research shows the importance of cultural particularity when diagnosing mental illnesses. In fact, in the adapted test 42% of the Moroccan and only 14% of the Dutch patients were not diagnosed as mentally ill at all. The large difference between the outcomes of the standard and the moderated tests may even be due to an overcompensation for cultural difference in the adapted version, which could be an interesting point for further research.
Photo: Flickr, davemmett
Zandi T, Havenaar JM, Laan W, Kahn RS, & van den Brink W (2011). Predictive validity of a culturally informed diagnosis of schizophrenia: a 30 month follow-up study with first episode psychosis. Schizophrenia research, 133 (1-3), 29-35 PMID: 22019074
Zandi T, Havenaar JM, Smits M, Limburg-Okken AG, van Es H, Cahn W, Algra A, Kahn RS, & van den Brink W (2010). First contact incidence of psychotic disorders among native Dutch and Moroccan immigrants in the Netherlands: influence of diagnostic bias. Schizophrenia research, 119 (1-3), 27-33 PMID: 20332065
schizophrenia, pscychosis, immigrants, migrants, moroccan, test, culture, misdiagnose