Let's now talk about eating disorders. Well, what are eating disorders?
They're characterized by a persistent disturbance of eating that impairs health
or psychosocial functioning. Different types of eating disorders include anorexia,
avoidant/restrictive food intake disorder, pica, binge eating disorder, bulimia,
and rumination disorder. So we'll take each of these in turns starting with anorexia.
Consider this case example. A teenage girl is brought to the doctor by her mother.
The girl is very thin, brags about her healthy diet and exercise routine
which involves very little caloric intake and also running over 20 miles, 3 times a week.
Well, anorexia nervosa has a lifetime prevalence in the US of about 0.6%.
It's much more common in females and it has a tendency to show up in adolescence.
There are two subtypes of anorexia, the restricting type and the binge eating/ purging type.
Check out these professions that have a really high risk for people developing anorexia.
The diagnostic criteria are as follows. There's a restriction of food that leads to a low body weight
given the patient's age, sex, developmental trajectory, and physical health.
There's an intense fear of gaining weight or of becoming fat, or persistent behavior
that prevents weight gain. There's a distorted perception of body weight and image.
And amenorrhea had previously been a requirement although it no longer is in the current DSM-5.
So, anorexia has the highest death rate of any mental illness.
Actually, 5 to 20% of people with anorexia will in fact die from it
because there are a lot of medical complications including myocardial atrophy,
mitral valve prolapse, there can be a pericardial effusion, bradycardia,
there can be a hypothalamic amenorrhea, there can be an antenatal and postpartum problem,
there can be osteoporosis, GI disturbances like gastroparesis, constipation,
and also a growth disturbance. In terms of the assessment, you wanna do laboratory tests
and be particularly attuned to looking for secondary dehydration in these patients.
In terms of lab tests, you're looking for disruption of their thyroid, elevated liver enzymes,
high cholesterol, carotenemia, you're looking for elevated blood urea nitrogen
so you're gonna do a BMP or a kidney panel, also checking for creatinine,
and also alterations in the hemoglobin and hematocrit which could be secondary to dehydration.
You wanna weigh your patients, and also obtain a bone density scan,
and you wanna take their vital signs. In terms of treatment, so patients can be treated
as an outpatient unless they are more than 20% below their ideal body weight.
In this case, that patient should be hospitalized. Some treatments can promote weight loss
so be very careful when determining what medications to give to your patients.
The first step in treatment of the patient with anorexia is actually to establish their cooperation.
They really need to join you in care and in forming a treatment plan
so it's important that you have a good therapeutic alliance. Some treatment options
that can be very helpful include behavioral therapy, family therapy,
and then supervised weight gain programs are imperative.
Again, medications can be helpful but be a bit cautious as some can actually promote weight loss.
We tend to think that antidepressants can be useful such as paroxetine or mirtazapine.
These can actually promote weight gain so that's something to consider with patients.
Treatment really depends on a multidisciplinary approach involving the doctors, nurses,
psychologists, dieticians, community nurses, and the family and also, ever so important
that part of the treatment team is in fact the patient who really needs to buy into
the plan or else they're not going to be adherent and have as good of an outcome.
So, what medical complications may occur if the patient with anorexia is actually refed too quickly?
So this is why it's so important to have a dietician involved
as well as other medical health professionals because you wanna be careful
to very slowly help your patient gain weight. If they do it too fast, here's what can happen.
They can get acute gastric dilation, fluid retention, they can actually go into congestive heart failure,
have cardiac arrhythmias, rhabdomyolysis, and it can ultimately lead to death
and that's why when patients are severely underweight they need to be hospitalized
so they can in fact be refed in a very controlled setting where they can be monitored for problems.
Remember that teenage girl who's running over 20 miles, 3 times a week.
Well, it sounds like from what we know from that case example,
she might be a classic example of anorexia. Let's talk a little bit more now
about avoidant and restrictive food intake disorder. So the criteria here are avoiding
or restricting food intake which may be based upon a lack of interest in food.
It can be a sensory characteristic of food, or a condition to negative response
associated with food intake following an aversive experience for example, choking or the like.
The eating behavior leads to persistent failure to meet nutritional and energy needs
as manifested by at least one of the following, clinically significant weight loss,
nutritional deficiency, supplementary feeding needing to be required,
or impaired psychosocial functioning. The eating or feeding disturbance is not due
to lack of available food, the disturbance does not occur solely in the course of anorexia or bulimia,
and it's not due to a general medical condition. Here's a question for you.
How do you calculate the body mass index or BMI?
It's weight in kilograms divided by height in meters, something that's often important to note
when it comes to determining your patient's needs and can sometimes be an exam question.
So we've summarized here a few of the eating disorders. We'll go on in another lecture
to talk about the others and you have a little bit of basis now of the diagnostic criteria
and some clues as to how to go about the treatment of your patient.