Editor—Rigg's news item about genetic testing for familial Alzheimer's disease in a Spanish hospital highlights the need to extend the current debate in the Spanish press to the scientific community.1 In spite of its high genetic penetrance, environmental factors can also determine the phenotypic presentation of familial Alzheimer's disease.2 Since the disease is currently incurable and no interventions have been proved to either prevent or delay the onset of the disease, considerations of the quality of life of future patients are paramount.
People who have been told their prognosis are faced with psychological problems that may be helped by regular counselling or psychological support, although neither the effectiveness of these interventions nor their long term effects have yet been shown.3 They have to live with the psychological effects (which in some cases have led to suicide) even though an effective treatment may have been developed or they may have died of something else by the time Alzheimer's disease occurs some 15, 20, or even 30 years later.
Relationships and life plans may be influenced substantially by the diagnosis. Should affected people inform future partners that they have this genetic mutation and may need full time care in the future? If they want children should the embryo undergo genetic selection?4
The social system is currently not prepared to provide support to these new patients in finding employment suitable to a working lifestyle that will be different from that of someone without the mutation. In addition, social security benefits do not take into account the future costs generated by the diagnosis (such as days off work). Insurance companies are unlikely to accept a person with a certain future disability, and if they did it would be at a high cost.
The patient could be invited to participate in studies of developing experimental preventive treatments that would entail them being subjected to various diagnostic tests and in taking drugs in clinical trials. Although patients would be very motivated to try to improve their future prognosis, the cost in terms of quality of life—for example, from side effects—may none the less be high.
Genetic testing could lead to a whole series of circumstances that may have a negative effect on the quality of life of people testing positive. Early diagnosis of the disease might unleash a process of premature medicalisation. The scientific community has already been called on to ensure that genetic technologies take social, ethical, and other aspects of quality of life into account and be based on evidence.5 Maybe we should ask whether we are trying to treat non-existent patients.
References
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