Commenting in the second episode of the three part Superdoctors series that “one of the most exciting frontiers of our age is stem cells“, Robert Winston goes on to ask “how will these cutting edge technologies change the way that you, and I, and are children are treated?” (Start – 00:04:02). Stem cell therapy is at the beginning of its expected transition from the laboratory to the clinical application. The programme seeks to distinguish the hype from the genuine developments and to examine some of the hard decisions that need to be taken. Several of the key ethical issues associated with stem cell research have been considered in posts about other programmes (see for example Are hybrid embryos an ethical step too far? – The Big Questions and Bioethics Briefing – Stem cells). This episode, however, is particularly useful for consideration of two issues:
- Public understanding of science and the management of expectations
- Clinical trials and “therapeutic misconception”
Public understanding of science and the management of expectations
Inevitably, there is a gap between the knowledge of scientist directly involved in a new biomedical breakthrough and the general public’s understanding of the issues. Unfortunately this difference allows for irresponsibly excessive and unrealistic claims from some researchers and clinicians regarding the current availability and effectiveness of treatments. As Winston puts it, this leads to a situations where “blind faith in unproven treatments often ends disastrously” (00:03:45 – 00:05:52).
By way of illustration, Winston meets with the parents whose son unfortunately contracted meningitis and fell into a ‘permanently awake’ coma (00:05:38 – 00:13:06). His mother could not accept the verdict of the doctors that his situation was incurable; “I wanted my son back”, she says. Searching the internet for treatments or cure, they discovered an American psychiatrist practicing in the Dominican Republic and an Argentinean clinic, claiming to have treated many diseases such as Parkinson’s disease, diabetes, multiple sclerosis and brain damage with stem cell therapy. The family travelled to both of the clinics so that their son could receive treatment with stem cell. The mother was convinced that there was some progress in his health, but having any possible spent over £180,000, their money ran out and their son eventually died.
- Do scientists have a moral obligation to ensure that the public has a realistic understanding of the current parameters of science and medicine?
- Should scientists and doctors do more to manage patient expectations of how beneficial a treatment might be?
- How do the media influence public understanding of science and medicine?
- Should the regulation of health services be the responsibility of national or international authorities?
Clinical trials and therapeutic misconception
The remainder of the programme focuses on the potential of stem cells to treat severe heart disease (00:16:56 – End). Every year in Britain over a quarter of a million people suffer from a heart attack, caused when one of the branches of the major arteries that supply the heart with oxygen becomes blocked. Through a procedure called angioplasty doctors can re-open the blocked artery. This procedure, however, does not repair the sections of dead heart tissue that result from a lack of oxygen (00:16:56 – 00:19:40). It has long been an ambition of doctors to find a way of regenerating the damaged tissue of the heart and the hope is that stem cells will provide the answer.
Alec, now 77, had his first heart attack when he was 30 years old and has since had five heart operations, leaving him unable to walk more than 20 yards (00:19:40 – 00:21:15). Doctors here now say there is nothing more that they can do for him, and so he travels to Germany for stem cell-based treatment. When asked why he had made this decision he replies “I don’t know of anything else that would give me what I need, which is virtually a new heart. Unless you’ve got some hope what is the point? Even if it doesn’t work, I’d have tried.”
Winston visits Alec’s doctor to discuss his condition (00:21:15 – 00:24:35). It is clear that Alec has had every available treatment; his doctor believes that despite the unknown potential of this treatment, as long as it is done in an ethical sound manner, he approves of the trip to Germany. Winston, however, has some concerns, believing the trip might be too risky for Alec. Nevertheless, he admits that he would find it very difficult to tell Alec otherwise.
The following questions are raised by this section:
In a double-blind placebo trial, why do only half the patients get the treatment?
Why do scientists keep secret the information of who has received the treatment from both the patients and the doctors?
How would a patient feel if they did not receive the treatment in the trial but later found that it did provide a benefit?
Do you think double-blind placebo trials are ethical? Suggest two arguments in favour and two against.
What alternatives are there to double-blind placebo trials? Why have clinical trials?
Additionally, this section (00:40:16 – 00:41:55) again raises the issue of patient understanding and the doctors role in ensuring this.
- What factors could have caused Alec to label stem cells as ‘magic cells’?
- Should doctors make an extra effort to confirm that Alec understands the true benefits of this experimental treatment?
The thoughts above highlight the very important issue of ‘therapeutic misconception’ (discussed in the previous post Wit: a window of tensions in clinical trials). This issue may arise when a patient has no other treatment option and is faced with the choice of no more treatment or trying an experimental treatment. Patients that opt for the latter may believe that these experimental treatments have been specifically designed for them, when in fact it may have little or no benefit. This belief is often encouraged by doctors keen to try out the experimental treatment. Even using the word ‘treatment’ suggests a therapeutic benefit, when in fact this is not yet known. When Alec talks about those ‘magic cells’, it suggests that he has an overestimation of their benefit, something also known as ‘therapeutic misestimation’.
Six weeks after the stem cell therapy in Germany, Alec believes he feels a little better, as he is not suffering with as much angina. He undergoes an echocardiogram to see if his heart’s ability to pump blood has got any better (00:48:05 – 00:55:35). The results suggest that there has been no improvement. Winston explains that since Alec knowingly received the treatment, rather than as part of a double-blind placebo trial, he may feel better for a number of reasons including the ‘placebo effect’ and not because of the stem cell therapy. In contrast, improvement in David’s condition after participation in the double-blind trial would be a more valid indication if the stem cell therapy outperformed placebo. However, six weeks after the start of the trial, David does not feel any better.
Despite this, David believes “things need to be discovered and invented and if it does me some good; great. But if other people can benefit from what the doctors have done to me, that’s equally as great” (00:55:35 – 00:57:13). This altruistic approach is difficult but at times essential for the progression of medicine, Winston (00:57:17 – end): “Medicine needs willing guinea pigs like David but it’s likely to be others who will benefit most. Like it or not the double blind placebo trial is the only way to answer the critical question about stem cell therapy.”
Superdoctors is an excellent resource for teaching about the intricate nature of patient expectations and the use of double-blind placebo trials. Superdoctors – Miracle Cures (TRILT: 00AC861F) was first shown on Thursday 28th August, at 21:00 on BBC1 and repeated on Saturday 13th September at 01:30.
Other useful sections
(00:28:26 – 00:31:06) When David has his bone marrow aspiration Robert Winston explains what stem cells are and what they do.
(00:31:19 – 00:34:51) This section shows how doctors inject the stem cells into David’s heart tissue
(00:42:44 – 00:48:32) This section shows how doctors use an alternative method to place the stem cells in Alec’s heart