Vigilance Is Required For Adequate Informed Consent

One of the main reasons for me writing this blog is to discuss medication safety and adverse effects. This is no small task since the orientation of most research and clinical work is making a diagnosis and where appropriate selecting the correct medication. A lot of work goes into those determinations but an equal amount of work needs to be directed toward managing common adverse effects and preventing serious adverse effects/events of the medication. In order to do that practitioners need to realize that they are treating a genetically diverse population. That means there will always be a subgroup of people who cannot tolerate medications. There will also be a subgroup of people who respond very well to medications and variations in between.

A good example is selective serotonin reuptake inhibitors (SSRIs). These medications are commonly first-line agents for depression and anxiety. About one person out of every seven will not be able to tolerate them. The same is true of every major class and psychiatric medications. That is a source of frustration for practitioners because it means that even if the correct diagnosis is made the optimal medication may not be available because the person cannot tolerate it. In the case of SSRIs, a person may not be able to tolerate any other medication in that class.

In addition to genetic heterogeneity affecting the pharmacokinetics and pharmacodynamics of drugs, patients are also taking other classes medications and have other medical morbidities that may contraindicate the use of certain psychotropic medications. In the case of bupropion, any history of eating disorder or current eating disorder, any seizure history, and any traumatic brain injury that may predispose to seizures are contraindications to using that medication. Appropriate medical care requires that practitioners are aware of all of the contraindications and precautions listed in FDA package inserts for medications.

What about the case of a healthy young person with no medical comorbidity who needs treatment for depression or anxiety. What is important for that person to know in order to safely take that medication? What should be explicitly discussed with them? What constitutes adequate informed consent? What can be done in the time a practitioner has to make the diagnosis and educate the patient? These are not trivial questions since most practices are scheduling patients every 15 minutes in some cases new patients are seen for 30 minutes. All that makes it seem like psychopharmacology is a very easy job but the information transfer during the sessions is critical and there is plenty of evidence that it is inadequate.

There is an excellent discussion of the problem by Rajnish Mago, MD in the references (2).  He considers a number of ways to assess and manage adverse effects including open-ended questions, checklists administered to the patient, structured interviews by clinicians, and spontaneous reports by patients. His review of this literature shows that the sensitivity and specificity of all of these methods are lacking and some of them take so much time they could not be applied clinically. He gave as an example of structured interviews administered by clinicians that take up to 60 minutes just to determine the adverse effects.  The other problem with determining the adverse effects is whether or not they can be attributed to the medication that has been prescribed. In clinical trials, researchers often estimate whether adverse effects/events are due to the medication or not. In practice that is a difficult determination due to both placebo and nocebo effects.

Vital signs and laboratory measures can also constitute adverse effect measurements. In psychiatry liver function tests, renal function including plasma creatinine and estimated GFR, CBC and ANC, TSH, T4, basic metabolic profile, electrocardiograms, and EEGs are all metrics that can be followed to determine medication effects. Vital signs should also be routinely done on anyone taking medications to check for effects on blood pressure, heart rate, and heart rhythm. Those measurements constitute more specific measures that could lead to clinical action.

There has been some emphasis on measurement-based practice that involves the extensive use of rating scales.  Many of the authors in this area seem to mistake rating scales as both objective and quantitative measures when they are neither.  I remain unconvinced that this is the best approach and think that it has resulted in the over medication of large numbers of people who have a certain rating scale score but no diagnosis.  There has been very little discussion of the analysis of longitudinal data and what these rating scale scores actually mean. The controversy in this area applies to both the diagnostic indices as well as the side effect indices. My approach in dealing with side effects is that they should be completely eliminated wherever possible and that irreversible adverse effects need to be avoided.

Dr. Mago’s paper reviews recommendations for improving adverse effect reporting and clinical trials and also his recommendations for clinical practice that basically come down to telling patients about all adverse effects that occur at a rate 5% greater than placebo and all potentially serious for life-threatening adverse effects even if they are rare. I am in complete agreement with those recommendations, and even have an approach that can work. It does require a degree of vigilance on the part of the clinician.

The attached table suggests why vigilance is required.  Psychiatrists need to be more vigilant than most physicians because no patient is expected to get complications or die as a direct result of our treatments. That historically has led the field to have a lower threshold for monitoring for potential side effects.  Given all of these constraints and the complexity of the situation is there a way to provide adequate informed consent about the medications that we prescribe?  I am talking about all physicians here and not just psychiatrists.  I think there is and I will walk through my process.

1.  I preface my remarks with my experience prescribing the medication: For example with common medications like naltrexone I will give an estimate of the percentage of people that tolerate the medication very well and the percentage that stop taking it and why. That sets an  expectation that a medication may or may not be well tolerated as a probability statement and that some people stop it because of adverse effects.

2.  I encourage people to do their own research. Anyone can pull up the FDA package insert on any medication these days by Googling: "[medication name] FDA package insert".  I tell them what to expect. I also tell them that I should be able to explain anything they find on the Internet about the medication if they have any questions or concerns. In the case of polypharmacy scenarios, I point out that the extremes of low doses and high doses of two agents and all of the combinations in between can be found this days with stated results ranging from very positive to very negative for the entire range of doses.  I also have the position that they can take as long as they want to do their own research and that in the meantime - no medication needs to be prescribed.

3.  I will discontinue the medication at any time and I am very explicit about that.  I do not expect anyone to "get used to" side effects because in my experience too many people get used to side effects and live with them on a long term basis.  I provide examples to illustrate the idea of living with side effects.

4.  I give them the MedlinePlus handout on the medication or show them how to get it.  The MedlinePlus handouts are really a product of American Society of Health-System Pharmacists (ASHP).  I have emails both into MedlinePlus and AHSP inquiring about the process they use to determine the bullet points for the listed precautions and tiers of side effects. At the time of this post I have not been contacted by either organization.

5.  I tell them the common side effects, contraindications to the medication, and precautions - specially if they are on a medication or have a medical condition that is flagged in the precaution section.

6.  I discuss sexual side effects as a common side effects of medications.  About 20% of the people I see have this side effect from SSRI type antidepressants.  I review the possible effects on sexual function including decreased libido, impaired excitation phase (erections, lubrication), impaired orgasm, and altered ejaculation (delayed, retrograde).  This is a difficult issue for many people who have found an antidepressant that works but produces this side effect. The analysis of the problem is complicated by relationship problems and the initial effects of depression.  It is important to outline a strategy to address the problem even if the patient's preference is to delay any medication changes. 

A good example is the antidepressant duloxetine. The contraindications are straightforward - uncontrolled angle closure glaucoma and recent use of a monoamine oxidase inhibitor (MAOI). Beyond that clinical worsening and suicide risk, hepatotoxicity, orthostatic hypotension and syncope,  serotonin syndrome or neuroleptic malignant syndrome, abnormal bleeding, activation of mania/hypomania,  seizures, effect on blood pressure,  clinically important drug interactions, hyponatremia,  use in patients with concomitant illness, urinary hesitation and retention, and  laboratory test abnormalities are all listed as warnings and precautions.  The most important one that I typically discuss is liver function abnormalities due to alcohol use.  Although this is not a contraindication - the package insert basically says that a person with this problem should not take duloxetine. I have had people want to take the medication despite this warning and have had to discuss a monitoring plan with them as well as letting them know that my read of the package insert is that this plan carries with it more risk than one that adheres to the recommendations by the FDA.   The package insert also lists two different groups of Treatment Emergent Adverse Reactions in tables.  Both are more common than placebo and occur in 5% or 2% of patients in clinical trials.  There is a subsequent list of side effects defined with these frequencies:

"Reactions are categorized by body system according to the following definitions: frequent adverse reactions are those occurring in at least 1/100 patients; infrequent adverse reactions are those occurring in 1/100 to 1/1000 patients; rare reactions are those occurring in fewer than 1/1000 patients." 

It takes a lot of practice to get the above informed consent discussions down to 10 minutes, especially when polypharmacy and other specific problems need to be addressed at the same time. Even then, it is important to present the information every time. Shortcuts can result in a patient experiencing an uncommon side effect and that leads to self doubt on the part of the physician of the form:

"If I had mentioned that problem like I usually do would it have led to a more timely intervention to reduce the adverse effect?"

That is a question that most physicians don't want to keep asking themselves and it is why my vigilance is high.

George Dawson, MD, DFAPA

References:

1: Bloom R, Amber KT. Identifying the incidence of rash, Stevens-Johnson syndrome and toxic epidermal necrolysis in patients taking lamotrigine: a systematic review of 122 randomized controlled trials. An Bras Dermatol. 2017 Jan-Feb;92(1):139-141. doi: 10.1590/abd1806-4841.20175070. PubMed PMID: 28225977; PubMed Central PMCID: PMC5312199.

2: Mago R. Adverse Effects of Psychotropic Medications: A Call to Action.Psychiatr Clin North Am. 2016 Sep;39(3):361-73. doi: 10.1016/j.psc.2016.04.005. Review. PubMed PMID: 27514294.

3: Tse L, Barr AM, Scarapicchia V, Vila-Rodriguez F. Neuroleptic Malignant Syndrome: A Review from a Clinically Oriented Perspective. Curr Neuropharmacol. 2015;13(3):395-406. Review. PubMed PMID: 26411967; PubMed Central PMCID: PMC4812801.