Wednesday, November 30, 2016

Add-on Services for IVF – The Evidence

ivf

In vitro fertilization (IVF) is the only option for many couples who want to have their own genetic child. This is an expensive procedure – it can cost up to $20,000 per attempt, with about a 40% success rate overall.

Couples going for IVF are often desperate to have their own child, and the uncertainty of success can be emotionally and financially draining. For this reason they are an especially vulnerable population when it comes to optional services (“add-on services”) that promise to increase the chances of success.

A recent BMJ article reviewed the evidence for 38 IVF add-on services typically offered in the UK: Lack of evidence for interventions offered in UK fertility centres. The title gives away the punch line – of the 38 services they reviewed, only one had any compelling published evidence of efficacy, endometrial scratch (causing minor trauma to the uterine wall to enhance the probability of embryo implantation). Even then the evidence was only “moderate.” The authors write:

Our appraisal of the evidence shows only one intervention, endometrial scratching, for which the review evidence robustly supports an increase in live birth rate, yet even this evidence is of only moderate quality, and the observed benefit is only in women with more than two previous embryo transfers.

That could easily be just random noise in the research. If you look at 38 different treatments, what are the odds that at random one of them will have an excess of false positive studies, and only in one subgroup (which is a red flag)?

The authors did not conclude that these treatments do not work, but rather that they are not supported by sufficient evidence to conclude that they do work. In the article they also list representative costs for these procedures, ranging from 50 pounds, to 3000 pounds.   A couple choosing a few optional procedures in the hopes of increasing their success could easily spend an addition 5-6 thousand pounds for one IVF cycle.

They included some of the costs to make a specific point – couples who are already spending a lot of money for IVF could be wasting even more money on procedures that are not backed by evidence. They also point out that many of the procedures are not risk free.

The procedures themselves are all superficially plausible. They include things like surgical sperm retrieval, intrauterine insemination, sperm DNA testing, and preimplantation genetic screening. I was interested to see that acupuncture was not even included in the list. I am not sure if the authors found it was not commonly offered (which is good, because it does not work) or that it was not necessary to review the evidence.

Standards of Evidence

The authors make several observations about the implications of this lack of evidence. They state:

  • Treatments with uncertain effects (benefits and harms) should be licensed for use only in the context of meaningful research.
  • People seeking fertility treatment need good quality evidence to make informed choices.
  • Patients may be desperate, and therefore vulnerable, and we have shown that fertility interventions are offered without supporting evidence to back up claims of effect.
  • Patients are unlikely to have specialist skills in seeking and critically appraising clinical evidence.

I am often struck when reading evidence-based reviews of conventional treatments of the cognitive disconnect between the mainstream context and the “alternative” or CAM context. All of the principles stated above apply to medicine in general. They are generally accepted as valid without controversy.

Patients are indeed often vulnerable. Unless they are specialists themselves, they will lack the education and skills to critically evaluate complex scientific literature. They should not be suckered into expending a great deal of resources on unproven treatments, which should only be offered in the context of appropriate clinical research.

In the CAM world, however, all of these basic and uncontroversial principles are discarded. A different professional and ethical standard applies (it shouldn’t, but it does in practice). In CAM world patients are not afforded proper informed consent. They can be charged for unproven treatments in the name of “Healthcare freedom.” Practitioners can even charge patients to participate in “research.” Patients are never seen as vulnerable, but rather are viewed as their own experts.

CAM practices have largely become “add-on” services offered by hospitals and practitioners. They are added to real medicine that works, to either mitigate side effects or “boost” the immune system, without compelling evidence that they actually do anything. They do nothing but add extra cost to patients and the healthcare system.

Over the last few decades the evidence-based medicine (EBM) movement within medicine has endeavored to strengthen the relationship between evidence and practice, to increase the standards of evidence. At the same time in history there has been a parallel movement to weaken the standards of evidence. Both groups have simultaneously advanced their agenda, mostly compartmentalized from each other.

The CAM movement, in fact, has bastardized the standards of EBM, declaring anything they want to be “evidence-based” without adhering to anything like the actual standards of EBM. There should be profound professional cognitive dissonance over this disconnect between the two movements within medicine.

This is why I think it is important to take every opportunity, when EBM standards are being championed within conventional medicine, to remind everyone that those principles must hold for all of medicine. That is actually all we are advocating at SBM, to have one consistent standard within medicine, and to eliminate the double standard that CAM advocates are trying to create.

Acupuncture and IVF

This gets back to acupuncture and IVF. The authors chose not to include acupuncture in this EBM review despite the fact that it is offered as an add-on treatment for IVF. This suggests they don’t consider acupuncture to fall within the purview of EBM.

There have been systematic reviews of acupuncture for IVF, which is actually much less plausible than the 38 treatments the authors did review. A 2014 systematic review concludes:

Since 1999, in spite of multiple trials and systematic reviews, the beneficial effect of acupuncture in improving the success of IVF remains unproven and debatable.

Some reviews have found possible benefit, and this is widely and uncritically reported. For example, a 2008 review was reported as showing a “65% increase in IVF success.” However, a closer look finds that this evidence is far from compelling.

First, the actual effect shown on the meta-analysis was an increase from a baseline of 27% to 32% – that is a 5% increase. The “65%” is a misleading relative increase.

More importantly, if you look at only those trials in which the baseline IVF success rate is in line with most modern clinics, there was absolutely no benefit to acupuncture. Only the trials in which the baseline success rate was unusually low (like 27%) showed an improvement. This strongly suggests that the improvement might be coming from just having better overall treatment in the clinical trial than the baseline for those clinics.

Also, most of the studies were not blinded at all. This was justified by arguing that pregnancy is an objective outcome, not subjective like pain. While this is true, there are ancillary effects (like relaxation for the patient and attentiveness from the treating physician) that may have made that small difference, especially if the baseline is far lower than most advanced clinics.

Overall the literature on acupuncture an IVF shows what we would expect from a treatment that does not work – no clear efficacy signal. Reviews only tease out barely positive results when they do multiple subgroup analyses, or when restricted to unblinded studies or clinics with a low baseline success.

If the same level of evidence were offered for a mainstream treatment I don’t think the reviewers would be as positive.

But clearly IVF clinics are willing to offer a range of treatments that are not backed by adequate evidence. The current BMJ review reveals this. The question now is how IVF clinics will respond to this article.

There is a tendency for treatment adoption to get ahead of the evidence. Research increasingly shows that if anything we should be more conservative, to raise the threshold where we think evidence is adequate to adopt new treatments.

The current review of IVF add-on treatments is further evidence of this fact.

 



from Science-Based Medicine http://ift.tt/2gIjOWN

No comments:

Post a Comment