ORIGINAL ARTICLE
Incapacity to give informed consent owing to mental
disorder
C W Van Staden, C Krüger
.............................................................................................................................
J Med Ethics
2003;29:41–43
What renders some mentally disordered patients incapable of informed consent to medical
interventions? It is argued that a patient is incapable of giving informed consent owing to mental dis-
order, if a mental disorder prevents a patient from understanding what s/he consents to; if a mental
disorder prevents a patient from choosing decisively; if a mental disorder prevents a patient from com-
municating his/her consent; or if a mental disorder prevents a patient from accepting the need for a
medical intervention. This paper holds that a patient’s capacity to give informed consent should be
assessed clinically by using these conditions necessary for informed consent, and should be assessed
specifically for each intervention and specifically at the time when the consent has to be given. The
paper considers patients’ incapacity to give informed consent to treatment, to give informed consent to
be examined clinically, and to give informed consent to participate in research.
W
hat renders some m entally disordered patients inca-
pable of informed consent? It may be claimed, for
example, that someone who is psychotic cannot give
infor med consent. This claim is over-inclusive, however, since
it is based on the general clinical features implied by a
diagnosis.
12
It is not based on the assessment of a particular
patient’s capacity to give consent, neither specifically for each
intervention nor at the time when the consent has to be given.
Such assessment may be guided by considering specific
conditions necessary for informed consent, especially those
that cannot be met owing to a mental disorder.
It is important to define with clarity these necessary condi-
tions, for decisions have to be made routinely about a mentally
disordered patient’s capacity to give informed consent if clini-
cal practice in psychiatry is to be ethically acceptable. We shall
illustrate how clarity about conditions necessary for informed
consent may be decisive clinically in the assessment of a
patient’s capacity to give informed consent.
We take it that a patient’s consent is required for any medi-
cal intervention unless s/he is incapable of consenting, or
unless the law requires a doctor to intervene even if against a
patient’s wishes.
3
But even when a doctor’s intervention is
required by law, it remains good ethical and clinical practice to
obtain a patient’s consent if at all possible.
4
For present
purposes, the medical interventions for which informed con-
sent is considered to be necessary are treatment interventions,
participation in clinical research as well as, rarely addressed in
the literature, mental and physical clinical examinations.
NECESSARY CONDITIONS FOR INFORMED
CONSENT
Notwithstanding standard conditions such as information,
5
trust,
6
and lack of coercion,
7
we shall confine the consideration
of the conditions necessary for informed consent to those that
typically cannot be met owing to mental disorder. Thus, they
are presented not as sufficient conditions, but each of them
being necessary. They are:
i) a mental disorder should not prevent a patient from under-
standing what s/he consents to;
ii) a mental disorder should not prevent a patient from choos-
ing decisively for/against the intervention;
iii) a mental disorder should not prevent a patient from com-
municating his/her consent (presuming that at least reasonable
steps have been taken to understand the patient’s communi-
cation if present at all), and
iv) a mental disorder should not prevent a patient from accept-
ing the need for a medical intervention.
The inability of some mentally disordered patients to meet the
first three conditions is commonly cited.
8–14
For some
disorders, these conditions are indeed appropriately identified
as those which at times cannot be met owing to the mental
disorder. Some mental disorders prevent patients from under-
standing the nature and purposes of a medical intervention, or
prevent patients from choosing decisively, or prevent patients
from communicating their consent. Examples are dementia
and learning disability of sufficient severity.
12
A manic episode
or a major depressive episode, for example, may entail marked
indifference, ambivalence, or indecisiveness, any of which may
prevent a patient from choosing decisively. Psychotic illnesses
may also cause patients significant difficulty in understanding
the nature and purposes of a medical intervention, or in
choosing, or communicating their consent, as found in—for
example, hebephrenic schizophrenia with markedly disorgan-
ised thoughts.
The Mental Health Act Code of Practice, reflecting the law
in England and Wales, emphasises a patient’s understanding of
the information about the proposed treatment, potential risks
and benefits of treatment, and the consequences of not taking
the treatment.
4
It also requires a patient to have the capacity to
make a choice. The Law Commission, in its consultation paper
on mental incapacity, and the British government also
consider “incapacity” in terms of “understanding” and
“communication”.
8–10
They say a mentally disordered person
should be considered unable to take a decision on medical
treatment in question if s/he is “unable to understand or retain
the information relevant to the decision, unable to make a
decision based on that information, or unable to communicate
a decision”. Medical defence societies
15 16
and various
papers
17–19
also take a patient’s understanding of information
about treatment as the main determinant of his/her capacity
to give informed consent.
See end of article for
authors’ affiliations
.......................
Correspondence to:
Dr C W Van Staden,
Department of Psychiatry,
University of Pretoria, P.O.
Box 667, Pretoria, 0001,
South Africa;
Revised version received
6 June 2002
Accepted for publication
20 June 2002
.......................
41
www.jmedethics.com
The main problem that renders some mentally disordered
patients incapable of informed consent does not, however,
involve these conditions. The problem is that mental disorder
prevents some patients from accepting that they need a medi-
cal intervention. We see this particularly in patients suffering
from psychotic illnesses such as schizophrenia. They may
understand the treatment proposed but still decline or refuse
it because, in their judgment, they are not ill or do not need
treatment for their difficulties. For example, a patient
suffering from psychotic illness may assert adamantly: “I
understand that you think I am ill, I understand your
proposed treatment and potential consequences of my taking
or my not taking the treatment, but I am not ill”, or: “I know I
am ill, I understand the proposed nature and purposes of the
treatment, but I don’t need treatment for it, because my illness
will disappear in the near future when I will be God”. Such
impaired judgment in patients suffering from psychotic
illnesses is inherent to their illness. We clinicians commonly
refer to this kind of judgment about their state of health as a
“lack of insight” into their condition.
That the patient’s acceptance of the need for a medical
intervention should not be prevented by his/her mental disorder,
is a condition necessary for informed consent. If any patient, even
if not mentally disordered, were to agree to treatment when s/he
did not accept that treatment was warranted or necessary, it
would cast serious doubt, to say the least, on whether such a
patient actually gave informed consent for this intervention. Of
course, there may be many reasons, valid or inv alid, for not
accepting that treatment is required. Clinical practice has it that
a patient’s lack of acceptance that treatment is necessary is dealt
with by honouring the patient’s choice irrespective of the
reasons giv en.
20
Pa tient refusals are presumed to be valid
exercises of autonomy. Congruently, the Law Commission has
recommended a “presumption against lack of capacity” and
that the resulting decision should not be regarded as invalid just
because it “would not be made by a person with ordinary
prudence”.
8
However, in the case of a patient who cannot accept that an
intervention is warranted or necessary, owing to a mental disor-
der, such a patient’s choice is not autonomous because it is
deter mined by the mental disorder. This also means that even
if such a patient were to agree to an intervention, it would be
farfetched to attest that s/he actually gave informed consent.
That a patient should believe the information about a
proposed intervention, as suggested in case law,
21 22
is also not
always the appropriate necessary condition to determine
capacity to give informed consent. For example, a deluded
patient may state: “I believe the information you have given
me about the proposed treatment, I believe the treatment may
be beneficial for some and even for me, but I shall not take it
because it does not befit me, being royalty from outer space, to
take the medicine from common humans”.
Of course, mental disorder does not necessarily prevent a
patient from accepting his/her illness and the need for a
medical intervention. Many patients, including those suffer-
ing from psychotic illnesses, do accept their illness and the
need for medical intervention. And, while some may not real-
ise the full extent of their illness, they can none the less give
infor med consent.
The clinician may find it helpful to have the abov e list of four
necessary conditions at hand when questions arise about a
patient’s capacity to giv e consent. It may be helpful in decisions
about specific treatments. For example, say consent is sought to
proceed with electro-convulsiv e treatment (ECT) for a severely
depressed patient who suffers from the Cotard’s delusion that
he is dead already and who therefore considers treatment to be
futile. Say the patient understands what he consents to—that is
ECT, he communicates his decision to go ahead with the ECT, and
he has chosen to follow the recommended advice. He thus meets
the first three conditions necessary for informed consent. He
will still not be capable of giving informed consent to the ECT,
how ever, because his mental illness prevents him from
accepting that he requires treatment.
The list of four necessary conditions may also be helpful in
decisions about a patient’s capacity to consent to participation
in research. For example, a patient who does not accept, owing
to his/her mental disorder, that s/he requires treatment is also
incapable of consenting to participation in research on medi-
cation for his/her illness. This is the case even though s/he
understands the nature and potential consequences of the
research, s/he chooses to participate, and communicates
his/her willingness to participate. The reason is that his/her
mental illness causes him/her to refute the need for efficacious
(non-placebo) treatment. S/he might even think that his/her
participating in the research serves to prove that treatment is
not really necessary. An argument against this stance might
claim that it is not necessary that this patient accept the need
for treatment, because a healthy person may consent to the
use of research medication even though s/he does not need it.
In fact, it is common practice to use healthy volunteers as
controls in medication research. The difference, however, is
that a healthy volunteer’s acceptance of not requiring the
treatment, is not affected by mental illness.
The capacity of a mentally ill patient to give informed con-
sent for a mental and physical clinical examination is a diffi-
cult issue practically, rarely addressed in the literature. The
problem is that it is hardly possible for a clinician to assess a
mentally ill patient’s capacity to give informed consent for a
clinical examination until s/he has examined the mental state
of the patient. Practically, this dilemma is eased in most civi-
lised countries by provisions of law—for example, a mental
health act, which may order or require a doctor to examine a
patient even without a patient’s consent. When informed con-
sent for a mental and physical examination is required,
though, the same conditions are necessary as for informed
consent to treatment and participation in research. A mental
disorder should not prevent a patient from understanding the
nature and purpose of the examination, from choosing
decisively whether to have it done or not to have it done, from
communicating his/her consent, and from accepting that the
examination is needed or warranted.
THE EXTENT OF INCAPACITY TO GIVE INFORMED
CONSENT
The Law Commission recommended, and the British govern-
ment accepted, a “functional approach” in determining
whether a person has the capacity to make a particular
decision.
8–10
This approach focuses on whether the individual is
able to make a decision at the time when it has to be made. It
allows for an individual to be incapable of making a particular
decision at one point in time, but indeed capable to make it at
another time—for example, after recovery. It also allows for
situations where the individual is capable of making some
decisions, but incapable of making others.
The conditions necessary to give informed consent, as they
have been identified above, are concordant with this
“functional approach” to making decisions. Capacity to make
decisions is not to be confused, however, with the capacity to
give informed consent. Capacity to make decisions is required
for someone to give informed consent, but informed consent
requires more than capacity to make decisions. It requires—
for example, trust and lack of coercion.
67
Moreover, informed
consent requires more than mere capacity. As seen above, it
requires that a mental disorder does not prevent “actual”
understanding of what is being consented to (rather than a
mere capacity to understand).
Furthermore, incapacity to give informed consent extends
to incapacity to give informed consent to medical interven-
tions for mental as well as physical conditions. For example,
say a patient were to agree to a medical intervention for his
gangrenous leg, but his mental disorder prevented him from
42 Van Staden, Krüger
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understanding the nature and pur pose of the intervention, or
prevented him from communicating his consent despite all
practical steps to understand him, or prevented him from
choosing decisively whether to have it done owing to severe
ambivalence, or prevented him from accepting the need for
the intervention. Then, it would plainly be mistaken to claim
that this patient’s assent to the intervention would constitute
infor med consent, for he f ails, owing to mental disorder, to
meet the conditions necessary for informed consent.
The same would apply in the following vignette. The patient
suffered from paranoid schizophrenia with multiple delusions
of persecutory, somatic, and grandiose types. He presented with
a peptic ulcer that had ruptured into the abdominal cavity—a
condition that required immediate life saving surgery. He
understood the nature and the purpose of the proposed surgery,
but he clearly communicated his choice not to have the surgery.
On further inquiry, he revealed his delusions that he had magi-
cal spirits in his abdomen, which were the sources of his super-
human powers . He was certain that opening his abdomen by
laparotomy would allow the magical spirits to escape, and with-
out these sources of power he would die. He took it that the
magical spirits would, in fact, heal the ruptured ulcer . Hence, his
decision not to have had the surgery. Clearly, this patient’s men-
tal illness prevented his acceptance of the need for surgery. He
could not give informed consent for the procedure. Even if he
had chosen to have the surgery despite having these delusions,
thus believing his cure would come from the magical spirits
rather than surgery, he would still not be capable of giving
informed consent. His illness would still prev ent his acceptance
of the real need for the surgery.
Similarly, say a patient were to agree to participate in
research on the treatment of an acute myocardial infarction,
but his/her mental disorder prevented him/her from under-
standing the nature and purpose of the research, or from
communicating his/her consent to par ticipate in the research,
or from choosing to participate in the research, or prevented
him/her from accepting that s/he did not have to participate in
the research. Certainly, such a patient’s assent would not con-
stitute informed consent.
Incapacity to give informed consent to be examined is also
not confined to examinations for mental disorders. For exam-
ple, when a patient who suffers from advanced dementia does
not understand the nature and purpose of, say, a genital
examination, he/she cannot give infor med consent for this
(physical) examination.
A patient’s incapacity to give informed consent to one inter-
vention should not be assumed to imply incapacity to give con-
sent to all medical interventions . It is well established in ethics
and law that a patient may be incapable of giving consent to one
intervention but capable of giving consent to another.
21
For
example, a patient suffering from schizophrenia may be capable
of giving informed consent to the treatment of his/her diabetes
but not to the treatment for his/her schizophrenia (or vice
versa). Simply, a patient may meet the conditions necessary to
give informed consent to the one intervention but not to the
other. Thus, each proposed intervention would require an
assessment of the particular patient’s capacity to give informed
consent for that specific intervention.
The same is true of capacity in other respects, and particu-
larly regarding performing actions. For example, a patient may
be incapable of giving infor med consent owing to his/her
mental disorder, yet be capable of another action, say, making
a cup of tea.
By acknowledging that incapacity to give informed consent
does not necessarily imply incapacity to perform other actions,
however, another clinical and ethical problem is laid bare: even
if a patient is incapable of giving informed consent owing to a
mental disorder, the question remains whether this patient is
also incapable of the actions of declining or even refusing a
medical intervention.
For practical purposes, the case may usually be that if a
patient is incapable of giving informed consent, this patient
would also be incapable of declining or refusing intervention.
Nonetheless, the conditions necessary for someone to be
capable of declining or refusing a medical intervention are not
quite the same as the conditions necessary for giving
infor med consent. Consider the role of understanding: one
might be capable of refusing an intervention without
understanding the intervention. For example, one could
refuse the hawker who approaches you even before you know
what he actually wants (to sell). It could therefore be wor th-
while teasing out, similarly to the present paper, the
conditions necessary to decline or refuse a medical interven-
tion, especially those conditions that cannot be met owing to
a mental disorder.
In conclusion, the clinical assessment of a particular patient’s
capacity to give informed consent in a case of mental disorder is
better informed by the consideration of conditions necessary to
give informed consent than by making inferences from the
general features implied by a specific diagnosis. An assessment
of a particular patient’s capacity to give informed consent by the
consideration of conditions necessary to give informed consent
may remain difficult clinically, yet such an assessment may
strengthen ethically a clinical decision about a mentally
disordered patient’s capacity to give informed consent.
.....................
Authors’ affiliations
C W Van Staden, C Krüger, Department of Psychiatry, University of
Pretoria & Weskoppies Hospital, Pretoria, South Africa
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