The Effect on Human Feelings Caused by Predictive Testing Methods for Degenerative Illnesses Like Alzheimer’s and Huntington’s Disease

In 1992, researchers were predicting that it would soon be possible to identify people who carried the gene for a chronic degenerative disease, like Alzheimer’s and Huntington’s disease, or even some types of cancer. No one believed that genetic research would say when people developed this disease, but they were sure that, one day, we would be able to genetically identify the people who would get them. However, in 1992, no one had the ability to say who would develop one of these terrible illnesses, so there was no research on the effects of predictive genetic testing on people’s emotions and well-being. No one could say if predictive testing would be beneficial or harmful.

In 1988, researchers in Canada launched the Canadian Collaborative Study of Predictive Testing. Its purpose was to study patients who had been told that they were at higher than normal risk for Huntington’s disease. The researchers wanted to identify the short and long term psychological effects and whether they were positive or negative.

Huntington’s disease is genetic. It is an autosomal dominant disorder, which means that a person has to inherit one defective gene in order to develop it. A person with a family history of Huntington’s disease has a 50% chance of inheriting it.

For this study, 208 people with a family history of Huntington’s volunteered to participate, but only 135 were included. All the participants were genetically tested and then assigned to one of three groups. Those who did not want to know the test’s findings were assigned to the control group. Those who wanted to know and were told they were at high risk were assigned to the second group, and those who wanted to know and learned that they had little risk of the disease were assigned to the third.

All the participants were given a battery of tests to complete. The tests were the Beck Depression Inventory, the general Well-Being Scale, and the General Severity Index of the Symptom Checklist 90-R. The tests were re-administered seven to ten days after being told about the risk, and then again at six months and 12 months.

Not surprisingly, the study found that the people at low risk had the lowest levels of depression and anxiety. But the study also found that the people who did not want to know the findings of their tests suffered the most deterioration in their emotional well-being. They even deteriorated more than the people who were told they were at high risk. Apparently, not knowing was worse than knowing. The uncertainty made their lives worse. In contrast, those who were told that their risk was high were able to plan and take control of their lives. They felt that their fates were in their own hands.

The most important finding of this study was that predictive testing did not have the harmful effects the researchers anticipated. Initially, there was a slight increase in depression and anxiety, but by the 7th day, their levels of depression and anxiety, on average, were falling, and although they never reached the same low level as the no-risk group, they were significantly below the levels of those who preferred to remain in the dark.

However, it would be wrong to conclude from this study that there are no harmful effects from informing people that their tests indicate that they are at risk for a life-threatening illness. The results reported in this study are average results, and not everyone is average. The researchers say that some of the participants in the high risk group suffered serious psychological damage. Their well-being suffered considerably. Every time they experienced an unfamiliar ache or symptom, they rushed to the doctor and demanded tests. They needed constant reassurance that their disease had not started. Fortunately, in no case did the bad news result in psychiatric hospitalization or suicide. In addition, roughly 10% of the participants in the no-risk group also had an increase in depression and anxiety. These people replaced their fear of dying with a fear of living. All their lives, they expected to die young, so they had not planned for a normal life. Now, they had to start planning for a future they never expected to have or enjoy and this frightened some of them.

There is a second reason why the results should not be generalized to everyone with Huntington’s disease. The sample of participants did not reflect the general population. Most of the participants were well-educated. The majority of participants were college graduates and their education may have affected the way they responded to the news.

Doctors have an ethical duty to do no harm, but they also have an ethical duty to tell patients the truth about their conditions so that they can make informed decisions about their care. An ethical dilemma could develop if informing patients of their condition might actually harm them. This is the dilemma of predictive testing. This study suggests that there is less harm than people might expect. The study found that most people with genetic diseases like Huntington’s actually benefit from being told about their risk. Being informed eliminates the uncertainty and anxiety that come with not knowing, and it allows people to move on to the next stage, which involves planning for the disease and its challenges.