Prophylactic medicine is the new medicine. The primary ethical issue brought up by the paper revolves around the notion of diagnostic testing. Everyone wants to try and catch the disease early so that we can come up with treatment options and help them salvage whatever quality of life they have left. The problem arises because these tests are not perfect. They sometimes miss the targets, leading to false negatives. They also sometimes hit targets that aren’t actually targets, leading to false positives. In both cases, there could be catastrophic consequences. It’s usually one or the other though. So when the condition is more dangerous than the treatment, it’s important to minimize the false negatives, such as in the case of cancers. When the treatment is more dangerous than the condition, however, it’s important to minimize the false positives, such as for hypercoagulability. In the case of schizophrenia, it appears that the symptoms of the condition outweigh the commitment and side-effects of treatment.
Schizophrenia is a mental disorder that emerges primarily during adolescent years. The symptoms include the inability to distinguish between real and unreal experiences, irrational thinking, abnormal emotional responses, and abnormal social behavior. Initially, these symptoms present as irritability or tense feelings, difficulty sleeping and difficulty concentrating. As the disorder progresses, the person will begin to feel a lack of emotion, strongly held beliefs that are not based in reality, auditory or visual hallucinations, problems paying attention, dissociated thoughts, bizarre behaviors, and social isolation.1 The hallucinations are the hallmarks of schizophrenia, and are also what can become dangerous to both the patient and the public.
Both genetics and environmental factors have been studied in their involvement in schizophrenia, and it appears to be a combination of both factors. Despite these studies, there is still very little known as to what actually causes schizophrenia, so the treatments mainly deal with the symptoms. Treatment options include medications, mainly antipsychotics, and also support programs and other behavioral interventions. There are adverse side-effects from the medications, including sleepiness, dizziness, weight gain, increased chance of diabetes and high cholesterol, feelings of restlessness or “jitters”, slowed movements, and tremor.1 Side-effects of the behavioral interventions include boredom and feeling like your time is wasted.
So, given these options, what would the optimal test to pick? One that minimizes false negatives, or one that minimizes false positives? From my subjective point-of-view, the symptoms are much more serious than the side-effects of the treatments. In fact, the major problem with false positives might not even be the treatments – it might be the undue stress and anxiety associated with the knowledge of having schizophrenia. There are social stigmas associated with mental disorders, so the worst consequence might be the feeling of not belonging in society anymore, or just not feeling normal.
In any case, that consequence is paled in comparison to the possibility of spiraling into a state of extreme paranoia and hallucinations. The NAPLS recognizes this need, and provides the test to address this need. They’ve created prediction algorithms that have an increased rate of being accurate with their positive calls, 74%-81% as compared to the 35% of the original diagnostic techniques.2 This increased positive predictive power (PPP) suggests a decrease in false positives. However, we want to minimizes false negatives, not false positives. The study also says that new predictive algorithms had lower sensitivity, which is the ability to actually detect afflicted individuals, than the original diagnostics, going from 29%-80% for the original to 8%-67% for the new algorithms.2 This is just the trade-off. They managed to lower false positives (but still enough for critics to be satisfied), but they raised the likelihood of false negatives. In this case, because of the greater severity of the condition than the treatment, the diagnostic needs more work in the opposite direction, in my opinion.
--James Zhang
Neuroscience Graduate Program
Want to cite this post?
Zhang, J. (2011). Response to “The Making of a Troubled Mind”. The Neuroethics Blog. Retrieved on
, from http://www.theneuroethicsblog.com/2011/12/response-to-making-of-troubled-mind.html
Resources cited:
1. “Schizophrenia.” A.D.A.M. Medical Encyclopedia. PubMed Health. 2010. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001925/
2. Cannon, T.D., et al. 2008. “Prediction of psychosis in youth at high clinical risk: a multisite longitudinal study in North America”. Arch Gen Psychiatry. 65(1):28-37.
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