A Collaborative and Therapeutic Approach for Measuring the Correct Body Weight in People with Anorexia Nervosa

Abstract

Diagnostic criteria for anorexia nervosa (AN) include significantly low body weight, fear of weight gain, and body image disturbance. Being severely underweight is associated with physical health risks, for example, electrolyte disturbances, epileptic seizures, cardiac arrhythmias, organ failure, and sudden death. It is also a perpetuating factor of AN. Therefore, the correct measurement of body weight is necessary for safe clinical management of AN. In clinical practice, there may be a requirement to attain a certain target weight before discharge from inpatient treatment or to prevent hospital admission. Schools, universities, and employers sometimes require a minimum body weight depending on the physical demands of the tasks at hand. Understandably, people with AN are therefore tempted to falsify their weight, for example, by water loading or using weights, to circumvent these restrictions and avoid disadvantages resulting from their mental health condition. In this chapter, we consider how to obtain an accurate assessment of body weight in the best possible collaborative, therapeutic, and motivating way.

1. Introduction

According to the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), anorexia nervosa (AN) is an eating disorder characterized by a restricted energy intake and a significantly low body weight, an intense fear of gaining weight, and a disturbed body image. DSM-5 distinguishes two subtypes, the restrictive and the binge-purge type. The restrictive type is defined by excessive dieting and physical exercise, whereas the binge-purge type describes periods of binge eating followed by self-induced vomiting or the use of laxatives [1].

The 11th edition of the International Classifications of Diseases (ICD-11) specifies the criteria of significantly low body weight as a body mass index (BMI) <18.5 kg/m² [2].

DSM-5 and ICD-11 use the BMI to rate the severity of AN. According to DSM-5, a BMI below 15 kg/m² indicates extreme, a BMI between 15 and 15.99 kg/m² severe, a BMI between 16 and 16.99 kg/m² moderate, and a BMI above 17 kg/m² mild AN.

In ICD-11, a BMI below 14 kg/m² indicates dangerously low body weight and a BMI between 14 and 18 kg/m² indicates a significantly low body weight. A BMI higher than 18.5 kg/m² is normal. In children, a BMI under the fifth percentile indicates AN according to ICD-11.

Being seriously underweight can have various harmful effects on the body, for example, electrolyte disturbances, osteoporosis, bone fractures, hypothermia, epileptic seizures, weak immunity, or even cardiac arrest and sudden death. In addition, starvation due to AN can lead to psychiatric symptoms such as memory problems, decreased cognitive flexibility, depression, and anxiety [3, 4].

Treatment of AN involves weight gain to manage the health risks that are linked to starvation. Weight gain is key in supporting other psychological, physical, and quality of life changes that are needed for improvement or recovery [5].

Therefore, treatment includes regular weighing (usually weekly for outpatients and twice weekly for inpatients) to document the therapeutic process and risk management. Exposure to weight gain needs to be carefully managed as it is associated with high levels of anxiety. In individual cases, where weighing is unbearable for a patient because of an overvaluation of the number on the scale, a collaborative decision to weigh the patient without sharing the body weight with them might be considered.

For the transition from inpatient treatment to outpatient treatment, there are often weight requirements alongside therapeutic milestones that are desirable for such a transition, for example, a regular eating pattern and the ability to attend psychotherapeutic groups and individual therapy and maintaining or increasing weight while on leave from inpatients.

For this chapter, we reviewed the literature on weight falsification in AN and performed internet searches. However, as there is little evidence published about weight falsification in AN, we have formed a team of authors that consists of professional peer support workers with lived experience of AN and clinicians with experience in the treatment of AN to fill the gaps in the literature with personal experience. We have tried to make suggestions on how the measurement of weight can be performed correctly but at the same time in a collaborative and therapeutically meaningful way.

2. Challenges of measuring the correct body weight

As fear of weight gain is a core diagnostic criterium of AN [1, 2], the falsification of weight is a frequently associated problem. In total, 30–50% of people with AN reported weight falsification during therapeutic weigh-ins in a web-based survey [6]. However, the underlying motivation may vary.

2.1 The potentially undesirable consequences of the correct body weight

Depending on the treatment setting, the correct body weight might have negative consequences for people with AN. A significantly low body weight might lead to the clinical recommendation of inpatient admission. For the person with AN, this means restricted freedom and an inflexible therapy and activity schedule on an inpatient ward. Therefore, patients with AN who anticipate such a recommendation might try to change the displayed weight on the scale without real weight gain [7].

For inpatients, a reason to manipulate weight could be the desire to be discharged to gain more independence, to be reunited with their family, and to meet friends which might all not be possible during inpatient treatment.

The daily routine and the food intake are often very controlled for inpatients in an eating disorders ward. However, progress in therapy, which is reflected by weight gain, might prompt an increase in daily leave from the ward and more options for food choices and meals outside the ward. Weight loss, however, might result in leave restrictions and bigger portion sizes. Therefore, weight falsification is a comprehensible effort to regain control.

As AN comes with an intense fear of gaining weight [1, 2], patients with AN falsify their weight to appear as if they were gaining weight because they are so scared of a weight increase. Thus, the scale might indicate an increasing body weight, while they are losing weight or maintaining their current significantly low weight. Some patients set themselves a maximum body weight, that does not align with suggestions made by the therapists.

Despite knowing that they do not make progress during therapy, some patients do not want to disappoint their therapists and their family members.

Another reason could be that people want to normalize their life (e.g., go to university, keep their driver’s license), for which a certain BMI is needed. A too-low BMI will not allow these “normal” things, as the risks included are too high.

2.2 Methods of weight falsification

The main methods of falsification are an increase in the body’s water content, the consumption of food with very few calories, and attaching weight to the body [6, 7, 8, 9]:

• Increasing the body’s water content

  • Water loading: Drinking large amounts of water or other liquids.

  • Going to the toilet less often to retain feces or urine.

  • Consuming high amounts of salt to increase water retention.

• Consuming food with very few calories

  • Eating high-fiber, low-caloric food, for example., cucumbers, sauerkraut.

• Using weights

  • Wearing weights under sweaters or around ankles.

  • Stuffing coins/weights in pockets or underwear.

  • Sewing weights into the seams of clothing.

  • Wearing heavy hair accessories or jewelry as well as adding weights in the hair/ponytail.

  • Stuffing weights in their cheeks.

  • Wearing padded clothing (bras, sweaters…).

  • Internal weights: Putting weights inside the anus or vagina.

2.3 Consequences of weight falsification

The falsification of weight can have various consequences for the patient and their health. Drinking large amounts of water, for example, can decrease sodium plasma concentrations, which can lead to fatigue, other electrolyte disturbances or seizures, and cardiac arrhythmias [10]. Putting weights internally or swallowing them might harm the internal organs.

Other potential consequences can be an erroneously early discharge from services with the consequent risks to their health and life.

Furthermore, others could be at risk as a result, for example, if a person with a very low BMI drives a car while they are unwell. Due to dizziness, extreme fatigue, blurred vision, and poor concentration, they may cause a car accident [11].

Premature discharge from inpatient treatment might limit further improvement or trigger a relapse into AN. Patients who are too unwell to manage their AN in the community might get rejected by outpatient therapists and dietitians.

3. Measures to prevent weight falsification

3.1 Additional physical examinations

Therapeutic weighing of people with AN is a continuous process of systematic desensitization toward acceptance of a higher and healthier body weight. However, it is also part of medical risk management and an assessment of a person’s strength or frailty. Additional physical examinations that can inform the management of undernourishment include:

• Mid-upper arm circumference measurement (MUAC): Measuring the circumference of the arm between the tip of the elbow and the shoulder on the upper arm.

• Grip strength: Static force measured by gripping a dynamometer as hard as possible.

Both parameters improve as nutritional intake improves and weight restores. Additional instrument-based examinations are the determination of starvation markers, such as the leukocyte count or thyroid hormones [12].

3.2 Specific methods of weight falsification and countermeasures

If the body weight of a person with AN seems implausible, the weigh-in should be repeated. This can be announced and unannounced which is often referred to as spot-weighing.

Table 1 provides an overview of methods of weight falsification and suggestions for possible countermeasures. However, some suggested approaches may not be appropriate for an individual patient as they might be perceived as too coercive. Examples of potentially inappropriately coercive measures are the use of metal detectors, patting a patient down, or letting them do jumping jacks. However, people with AN, like any other person, have an individual perception of shame, and the use of a metal detector might be less coercive for an individual patient than lifting their gowns.

Method of weight falsification	Measures to prevent it from happening
Water loading	Limited access to water before weigh-ins. Checking rooms for empty water bottles or weights. Supervised toilet visits before weigh-in. Blood drawing and measurement of sodium levels before or after weighing. Mandatory toilet use before weigh-in. Observing whether patients use the toilet shortly after weigh-in.
Consumption of salty foods	Measurement of blood sodium levels.
Wearing weights and/or heavy clothing; hiding weights in hair or clothes	Weighing in light gowns or underwear. Shaking out the hair. Letting the patient lift the gown to show that there are no weights hidden underneath. Using metal detectors. Patting down the patient.
Internal weights (e.g., anus, vagina, cheeks)	Jumping jacks to dislodge any weights. Checking the mouth.

Table 1.

Methods of weight falsification and suggestions for possible countermeasures.

The countermeasures should be explained to the service user and individually tailored to meet their needs and support therapy in the best way possible. Some measures are only feasible in an inpatient setting. Not all approaches are appropriate for all patients and might be perceived as too coercive. For further information, see [6, 10].

3.3 Working collaboratively to prevent weight falsification

Transparency is a key aspect of communication around body weight. Clinicians should always maintain a therapeutic and supportive stance with the service user regarding their recovery and recognize that any weight falsification is a symptom attributable to the eating disorder. Direct questions should be asked with compassion, for example, “Many patients report that they have water loaded or tried to falsify their weight in any other way? Has this happened to you?”

The therapists should clarify the reasons for weight frailty-checking and should explain that the procedures are in place for every patient, out of concern for their well-being.

The expectation is that a gradual trajectory of change will be seen (occasional outliers can be ignored). Ongoing weight loss and weight falsification will have consequences, but the therapists and clinical staff will try to understand and support the patients with both.

Overall, it is important to be as transparent and reassuring as possible, to make the experience as minimally stressful as possible. A strong therapeutic relationship can help the service user to feel more comfortable, decreasing the need for them to falsify their weight, or be more open about this. Table 2 provides examples of useful questions and phrases.

Communication goal	Examples	Rationale
Ask direct but compassionate questions before the weigh-in	“Many patients have told me that they water loaded before being weighed. Have you water loaded today?” “We know that the AN urges people to falsify their weight. Have you attempted weight falsification before this weigh-in?”	Encourage honesty, giving the option of talking about the weight falsifying.
Being transparent	“We are noticing some ups and downs in your weight over the last few weigh-ins. I am concerned that some of the weights we are seeing may not be real. Is there anything that you would like to talk about regarding this?”	Giving the service user clarity and preparing them for what will come up, thus helping them to feel prepared and more comfortable and less overwhelmed.
Showing compassion	“This must be really hard for you.” “You might feel very (emotion) right now and that’s okay.”	Making the patient feel heard and cared for.; Improves communication between service users and staff.
Reassuring and comforting the service user	“I know how hard this is for you, but I am here to help and if we do not know your real weight, it is not safe as we cannot accurately assess the risks to your physical safety.” “These are routine measures that we use for everyone.” “I am here to support you.”	Reassuring the service user that the team is always here to support them and that they are not singled out for special treatment.

Table 2.

Questions and phrases to improve the communication regarding body weight and its measurement to prevent weight falsification.

4. Conclusions and future perspectives

Even though weight falsification is a frequent clinical problem in the treatment of AN, little research has been done so far. Our chapter is only a first step which has been based on the scarce literature, and the experience and opinion of ED specialists and service user representatives. However, standardized approach to measure weight falsification and generally accepted methods to prevent weight falsification from happening are not available. Current treatment guidelines do not address this issue, even though some hospitals have local policies in place. Thus, research on weight falsification, its consequences and prevention is needed. It should take place in different settings, for example, outpatients, day care, and inpatients. Being weighed and seeing numbers on the scales can be a highly stressful and emotional experience for patients struggling with eating disorders, therefore it is highly important that empathy and compassion are at the forefront of further research and strategies to support service users in this area. A more open approach to encouraging discussion in this area would be appreciated. As weighing should become a collaborative process, methods to improve trust and the therapeutic relationship should be developed with the involvement of service users, their carers, and ED professionals.

Measuring the correct body weight might not only improve the assessment of physical health consequences of AN but could also lead to a better understanding of the emotional needs of people with EDs. For example, a recently published study has found that a higher BMI was associated with more severe ED psychopathology, more depressive symptoms, anxiety sensitivity, experiential avoidance, and lower mindfulness in patients across the whole spectrum of restrictive, binge-purge, and atypical AN [13]. Furthermore, recent research indicates that body weight at the start of inpatient treatment as well as weight gain kinetics during inpatient therapy for AN might help to predict treatment outcomes, improve clinical decision-making, and manage expectations of patients and clinicians [14]. Thus, a collaborative and more accurate way of measuring body weight might improve the clinical formulation and the decision-making process and lead to better treatment success and a more pleasant treatment experience in people with AN.

Acknowledgments

The authors would like to thank service users and staff members of the inpatient, day care, and enhanced treatment team ED services at the South London and Maudsley NHS Foundation Trust (SLaM), London. They would also like to thank their colleagues at the South London Partnership (SLP) for their helpful input and insights.

Conflict of interest

The authors declare no conflict of interest.