Psychological and nutritional evaluation

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Chapter 54 Psychological and nutritional evaluation

Introduction

The post-bariatric patient presenting for body contouring evaluation presents unique challenges for the plastic surgeon. The field of body contouring plastic surgery for the post-bariatric patient is rapidly evolving and has mirrored the growing popularity of surgical weight loss procedures. Even as the operative experience in this population of patients has grown, the complication rates of body contouring procedures after massive weight loss remain significant.13

Wound-related complications including dehiscence, necrosis, delayed healing, infection, hematoma, and seroma formation can be linked to nutritional deficiencies, which may be subclinical and unmasked by the demands of undergoing a plastic surgery procedure.4 With the need to optimize patient safety, there has been greater focus in the plastic surgery literature on the preoperative evaluation of the post-bariatric surgery patient, with particular attention to nutritional assessment.58 Weight loss and maintenance with appropriate supplementation is no small feat after surgical weight loss, and requires compliance and psychological wellbeing. Surgical success and patient satisfaction after body contouring surgery ultimately depend upon a patient’s mood stability and capability of adopting a healthy lifestyle.

This chapter outlines the nutritional and psychological considerations in the evaluation of the massive weight loss patient. New methods of preoperative assessment and treatment protocols could materialize through thoughtful contemplation of the various risks unique to this patient population.

Nutritional Considerations for the Post-Bariatric Patient

Bariatric Surgery History

The gastrointestinal physiology of post-bariatric patients differs according to the type of bariatric procedure performed. It is therefore important to obtain a bariatric surgery history, since this will largely predict the type of nutritional deficiency for which the patient is at greatest risk.9,10 Bariatric procedures can in general be categorized as being restrictive, malabsorptive, or a combination of both (Table 54.1). Malabsorption is achieved by bypassing a portion of the proximal small bowel, leaving less absorptive surface for ingested nutrients, whereas restriction is achieved by either reducing the size of the stomach or by placing a mechanical device to restrict food intake. Although purely restrictive procedures do not alter the normal digestive pathway, nutritional deficiencies may develop nevertheless due to restriction of caloric or nutrient intake, maladaptive eating behavior and digestive symptoms. The Roux-en-Y gastric bypass (RYGB) is considered the gold standard procedure and remains the procedure most commonly performed in the United States. This procedure has components of both restriction and malabsorption. Worldwide, experience with placement of the purely restrictive laparoscopic adjustable gastric band (LAGB) is greatest.11 Approved by the FDA in 2001, the LAGB has quickly become the second most common bariatric procedure in the US, with favorable longer-term results and public perception that it is the least invasive of surgical procedures.1214

TABLE 54.1 Common Types of Bariatric Surgery Procedures Performed in the United States

  Restriction Malabsorption
Roux-en-Y gastric bypass (RYGB)    
Standard + + +
Long-limb + + + +
Laparoscopic adjustable gastric band (LAGB) + + +  
Biliopancreatic diversion (BPD) + + + +
BPD with duodenal switch (BPD/DS) + + +

Weight Loss History

In general, gastric bypass patients will undergo rapid weight reduction in the first 3 months, reaching a stable plateau within a 12 to 18 month period.15 Patients with the LAGB have a much slower rate of weight loss, which may not peak until 3–4 years following placement of the device.10,12,14 Even though many post-bariatric surgery patients will have lost in excess of 45 kg (100lbs), quite a few will plateau with a body mass index (BMI) that remains high at the time of presentation for plastic surgery. Furthermore, a significant percentage will still be classified as obese at the time of plastic surgery.6,16 Wound-related complications that may be due to pre-existing micronutrient deficiencies found with obesity17 may therefore be further compounded by the effects of bariatric surgery, which may produce malabsorption of nutrients, bile salts and electrolytes, as well as intolerance of particular foods.

Ideally, post-bariatric patients should be within 10–15% of their goal weight at the time of evaluation for plastic surgery, fluctuating no more than a few kilos over a 3–6 month period.18 A greater decrease in BMI following bariatric surgery, increasing age, and the presence of dumping syndrome may indicate a greater risk for nutritional deficiency.5 Although intestinal adaptation can be expected to occur within 1–3 years with stabilization of metabolic derangements,10 the post-bariatric surgery patient remains at risk for both macronutrient and micronutrient deficiencies. Furthermore, many post-bariatric surgery nutritional deficiencies tend to worsen over time.5,19,20 Although bariatric surgery has been in practice for at least several decades now, evidence-based guidelines regarding optimum nutritional supplementation following surgery are still lacking.9 Despite empiric vitamin and mineral supplementation (Table 54.2), deficiencies are prevalent in post-bariatric surgery patients presenting for plastic surgery.5

TABLE 54.2 Routine Vitamin and Mineral Supplements Following Bariatric Surgerya

Supplement Dosage
Multivitamin 1–2 daily
Calcium citrate with vitamin D 1200–2000 mg/d + 400–800 U/d
Folic acid 400 µg/d in multivitamin
Elemental iron with vitamin Db 40–65 mg/d
Vitamin B12 ≥350 µg/d orally
  or 1000 µg/month intramuscularly
  or 3000 µg every 6 months intramuscularly
  or 500 µg every week intranasally

states are treated beyond these recommendations.

From Mechanick et al10

aPatients with preoperative or postoperative biochemical deficiency.

bFor menstruating women.

Protein

Protein deficiency is a significant risk for bariatric patients and should be of concern for plastic surgeons, since adequate serum protein levels are necessary for normal wound healing.21 Importantly, protein malnutrition after weight loss surgery cannot be excluded by history alone and serum concentration should be measured. Bariatric surgery can produce a combination of catabolism, malabsorption, and intolerance to protein-rich foods, leading to depletion of total body proteins.22 Protein malnutrition, in turn, may lead to increased inflammation and decreased tensile strength of surgical wounds as they heal. Large wounds from major surgery can increase protein demands for healing by 25% during the postoperative period.23 Furthermore, low serum albumin has been shown to be a strong predictor of increased morbidity and mortality, in particular due to sepsis and major infections.24 Greater decreases in BMI following bariatric surgery and the presence of dumping syndrome are found to be significant predictors of hypoalbuminema in bariatric surgery patients presenting for plastic surgery.5

Quantitative assessment of daily protein intake is important, since many patients will fall below 50% of the recommended daily intake of protein. Low prealbumin levels have been reported in up to 38% of post-bariatric surgery patients.6,10 Daily protein intake for the post-bariatric surgery patient is recommended in the range of 60–120 g/day,10,25 with those preparing to undergo major body contouring or reconstructive surgery advised to consume no less than 1 g/kg/day,5 typically by way of supplementation. In severe cases of protein calorie malnutrition, hospitalization for hyperalimentation may become necessary.

Iron

All bariatric surgery patients are at risk for developing iron deficiency, in large part due to an intolerance to red meat, which may lead to microcytic anemia.10,20 In a population of patients presenting for plastic surgery, the most common deficiency of vitamins and minerals tested was iron at 39.7%.5 Menstruating women are at greatest risk and will often receive oral supplementation by way of ferrous sulfate, fumarate, or gluconate (320 mg twice a day). Vitamin C can help iron absorption and increase ferritin levels. Intravenous iron may be necessary for severe or recalcitrant deficiency.

Vitamin B12 and Vitamin B9 (Folate)

The gastric bypass patient population is at greatest risk for developing vitamin B12 deficiency, due in large part to maldigestion.26 This deficiency tends to increase over time, despite oral supplementation with crystalline vitamin B12,27 and may lead to macrocytic anemia and neurologic sequelae. Supplementation with oral crystalline vitamin B12 (350 µg/day) or intranasal vitamin B12 (500 µg/week) is typically provided. In cases where adequate levels cannot be maintained, parenteral supplementation (1000 µg/week or 1000 to 3000 µg every 6–12 months) may be necessary.10 Vitamin B12 status should be evaluated on an annual basis. Folate deficiency may be seen in up to 38% of gastric bypass patients, which can lead to megaloblastic anemia and an increased risk for neural tube defects during pregnancy.28 In most cases, folate supplementation (400 µg/day) is adequate with the amount contained in a multivitamin preparation.

Vitamin B1 (Thiamine)

Thiamine deficiency can lead to severe neurologic compromise, including Wernicke–Korsakoff encephalopathy. Deficient states can be reached in a relatively short period of time, in particular in the post-bariatric surgery patient with protracted nausea and vomiting. Subclinical deficiency can be quickly unmasked by the routine administration of glucose-containing intravenous fluids,4 whereby impaired glucose metabolism may precipitate central nervous system deterioration.29 A low index of suspicion should be maintained for patients presenting with vague neurologic symptoms, including weakness, numbness, forgetfulness, or with subtle signs of peripheral neuropathy on physical exam. Although adequate daily requirements are typically met with a multivitamin, patients with persistent vomiting should be screened for deficiency.10 Patients who develop neurologic signs and symptoms suggestive of Wernicke–Korsakoff encephalopathy should receive aggressive parenteral supplementation with thiamine (100 mg/day) for 1 to 2 weeks, with subsequent oral supplementation (100 mg/day) until neurologic symptoms resolve.10

Calcium and Vitamin D

Calcium and vitamin D deficiency are predominantly seen following procedures involving malabsorption. This occurs because ingested calcium and fat-soluble vitamin D can no longer be absorbed in the bypassed proximal small bowel, in addition to maldigestion from loss of acid action. A significant number of patients become intolerant to dairy products as well. Postmenopausal women in particular are at longer-term risk for developing secondary hyperparathyroidism and metabolic bone disease, including osteoporosis, osteopenia, and osteomalacia.3032 Following malabsorptive bariatric procedures, calcium and vitamin D deficiency have been reported in 25–48% and 50–63%, respectively,10 of patients at 4 years. Low serum albumin is a strong predictor of metabolic bone disease,33 and rapid or extreme weight loss also contributes to bone loss outside of nutritional and hormonal influences.10,34 Patients who have had a malabsorptive procedure should receive regular monitoring of bone metabolism and mineral homeostasis. Markers of increased bone turnover such as bone-specific alkaline phosphatase and osteocalcin may be the most sensitive in detecting metabolic bone disease.10 With increased awareness of the prevalence of metabolic bone disease following bariatric surgery, routine supplementation with elemental calcium containing vitamin D in the range of 1200 to 2000 mg daily is recommended. Vitamin D can be further supplemented with ergocalciferol, 50 000 IU one to three times per week, with parenteral vitamin D reserved for severe deficiency.10

Perioperative Considerations

The timing of plastic surgery is important when evaluating the post-bariatric patient. Ideally, evaluation for body contouring surgery should take place no sooner than the 12 to 18 month period required for weight stabilization.10 Patients who have either failed to lose weight or have regained a substantial amount of weight might benefit from further evaluation by the bariatric multidisciplinary team. Problems may include maladaptive eating behavior associated with a psychological disorder, loss of integrity of the gastric pouch, or need for band adjustment.9,10

It is clear that life-long surveillance for nutritional deficiencies is important for all bariatric surgery patients.38,39 Continued multidisciplinary evaluation is important, since a significant proportion of patients may be noncompliant with regard to nutritional supplementation or lack ongoing evaluation of their nutritional status. Ideally, evaluation of the post-bariatric patient prior to any major plastic surgery should include workup by a dietician familiar with bariatric surgery patients to help assess adequacy of protein intake and deficiency with regard to vitamins and minerals,40 since proper nutritional supplementation can significantly reduce complications in this population of patients.6 Current guidelines for regular laboratory evaluation of the bariatric surgery patient are extensive (Table 54.3). Ongoing education of the patient regarding the importance of nutrition can be further reinforced during the postoperative period with support group meetings, which are often organized by bariatric programs, as well as by a growing number of centers dedicated to excellence in the post-bariatric plastic surgery patient.41 This can be very instrumental in helping the patient maintain healthy dietary choices by providing regular feedback from nutrition experts, psychologists, guest speakers and a forum for sharing experiences with fellow post-bariatric surgery patients.

TABLE 54.3 Recommended Long-Term (>1 Year) Biochemical Surveillance of Nutritional Status Following Malabsorptive Bariatric Surgery Proceduresa,c

Procedure RYGB BPD, BPD/DS
Frequency Annually 3–6 months depending on symptoms
Laboratory tests CBC, platelets Same as RYGB, including the following:
  Electrolytes Albumin, prealbumin
  Glucose Fat-soluble vitamins (6–12mo)
  Iron studies, ferritin Vitamin A
  Vitamin B12 25-Hydroxyvitamin D
  Liver function Vitamin E
  Lipid profile Vitamin K and INR
  25-Hydroxyvitamin D Metabolic bone evaluationb
  Optional: Intact PTH (6–12mo)
  Intact PTH Urine N-telopeptide (annually)
  Thiamine  
  Osteocalcin (as needed)  
  RBC folate Trace elements (annually or as needed)
  Zinc  
  Selenium  
  Miscellaneous (as needed)  
  Essential fatty acid chromatography  

aCBC = complete blood cell count; PTH = parathyroid hormone; RBC = red blood cell; INR = international normalized ratio.

bDual-energy X-ray absorptiometry should be performed annually to monitor bone density.

cAdapted from reference 10.

Psychological Considerations for the Bariatric Patient

Psychological issues related to morbid obesity incontrovertibly impact bariatric surgery outcomes. Before surgery, about two-thirds of patients appear to have at least one psychiatric diagnosis.42,43 In one large study, 66% of patients had a lifetime history of at least one Axis I diagnosis (clinical disorders including major mental disorders), with 38% meeting Diagnostic and Statistical Manual criteria at the time of preoperative evaluation. Moreover, 29% of this group had one or more Axis II disorders (underlying pervasive personality disorders), whereas 27% had a lifetime incidence of binge eating disorder.43 Similar rates of diagnoses of Axis I and II disorders are reported elsewhere.44,45 A dominant finding is a high incidence of mood and personality disorders, destructive eating behaviors, and poor body image in the morbidly obese patients. Although massive weight loss improves some of these issues, the improvement appears to be transient. The patient’s psychological profile appears to have a significant impact on successful weight loss, but weight loss appears to have a more transient impact on the psychology.

Depressive disorders are the most common diagnoses in the bariatric population, followed by anxiety disorder.46 The incidence of depressive disorder in bariatric surgical patients ranges from 4.4% to 53% in the literature.47,48 Depressive symptoms negatively impacted physical function and increased eating in response to negative emotion and impaired appetite regulation.49,50 Although female patients were more depressed than their male counterparts, their postoperative psychological improvement was also more significant.51

While depression and anxiety disorders are the most prevalent, other diagnoses are also noteworthy. High incidences of somatization (29.3%), social phobia (18%), hypochondriasis (15%), and obsessive–compulsive disorder (13.6%) were found in the bariatric population.47 A series of patients treated at a bariatric surgery clinic demonstrated a 72% incidence of personality disorders, including histrionic, borderline, schizotypal, and passive-aggressive.52 Compared with published norms, the patients undergoing bariatric surgery were consistently found to be psychopathically deviant or disordered in their personality traits.53,54 Interestingly 32.6% had lifetime diagnoses of substance abuse disorder, suggesting that substance abuse and weight problems may share some common foundation.43

Binge eating disorder (BED), marked by consumption of an objectively large quantity of food in a brief period during which time a person experiences subjective loss of control, has been extensively studied in the morbidly obese presenting for weight loss surgery. BED has a reported incidence of anywhere from 4% to 50% in the bariatric population, although the true incidence is likely closer to 10%.47,55,56 Patients with BED had more depressive symptoms and associated minor disturbances of eating behavior such as grazing and night eating.57 Although some studies reported that nonbinge eaters had a significantly higher excess body mass index loss than binge eaters,58,59 other long-term studies determined no difference in ultimate weight loss impact between patients in the BED and non-BED groups.57,60 However, binge eaters had more eating disturbances such as less restriction, more disinhibition, more hunger, as well as more psychopathological traits (passive-aggressive, aggressive-sadistic, manic, ethanol dependence, major depression).61 One study found that 46% of patients who had undergoing bariatric surgery reported loss of control over eating marked by objective or subjective bulimic episodes.62

Body image dissatisfaction is significantly greater in the morbidly obese compared with normal-weight control subjects. Body image dissatisfaction is more prominent in women and is associated with a higher incidence of depression, low self-esteem, and perfectionism.6365 After undergoing bariatric surgery and weight loss, patients improved in self-image and self-satisfaction, sometimes into published normal range.66,67 However, self-disparagement and preoccupation with body shape remained significantly different from control subjects, suggesting that some negatively charged aspects of body image remain, regardless of weight loss.68 Body contouring surgery after weight loss also further improved body image and was independent of mood.69

Overall, the psychology of the morbidly obese influences perceived and real outcomes of massive weight loss. Mental health tends to improve in the first couple of years after weight loss surgery, but the positive transformation may not be enduring.46 Massive weight loss can lessen depression, anxiety symptoms, paranoid ideation, and improve interpersonal relationships.70,71 The literature suggests, though, that improvements in mood deteriorate over time49 and that psychiatric abnormalities, negative personality profiles, detrimental eating patterns, and negative body image attitudes persist to some degree despite overall improvements in psychological profiles.

Discussion

The patient who has undergone bariatric surgery undergoes a tremendous physical transformation, as well as a complete nutritional and lifestyle overhaul. It is only natural that during this same period patients also undergo a psychological upheaval. Improvements in body image, social activity, social satisfaction, and satisfaction with life are seen in conjunction with massive weight loss.

Although many of the outcomes of bariatric surgery are quite positive, it would be inaccurate to paint a rosy picture. Nutritional complications are not only common, they are the norm among patients who undergo bariatric surgery. Patient noncompliance is the most important factor in the development of postsurgical nutritional deficiencies, with noncompliance with oral supplementation estimated at 33% to 64%.72 Some personality traits among the morbidly obese, including hypersensitivity and poor impulse control, are believed to preclude adjusting to demands imposed by bariatric surgery.73 After surgery, patients who undergo bariatric surgery are asked to follow strict regimens of diet, exercise, and vitamin intake. Perhaps these demands are excessive in a population predisposed to binge eating, maladaptive psychological responses, and underlying depressive symptoms.

Many patients have a psychological relationship with food that extends beyond nutritional needs. In many patients after bariatric surgery, satiety increased and the rapidity of eating decreased.74 Patients with preexisting psychiatric abnormalities continued to engage in more destructive eating patterns such as binge eating and disinhibition.48,75,76 Emotional eaters tend to eat to fulfill a psychological vacancy rather than physical need. It’s not surprising, then, that even after physiological and anatomic alteration, patients who undergo bariatric surgery should reinitiate their prior relationship with food, maladaptive or not. In a time of stress, individuals often turn to comfort foods; is it so surprising that after a major surgery, patients who have undergone bariatric surgery have difficulty adhering to a very foreign regimen of small, protein-rich meals and vitamin supplementation? Although the nutritional failures are not to be taken lightly, it is also important to ensure continued psychological health during this tremendously stressful period. Many of these individuals eat as a maladaptive coping mechanism for psychological problems, contributing to obesity.56 Optimization of psychological treatment and social resources can only help thwart the negative impulses and social stress that revive old habits.

Ultimately, massive weight loss from bariatric surgery initiates a remarkable physical transformation that often moves on into a revolution in personal relationships, body satisfaction, and social standing. Nutritional complications of bariatric surgery are, for the most part, correctible with careful adherence to a protein-rich diet and vitamin supplementation, as well as frequent monitoring. Proper identification of pre-existing maladaptive personality, eating, and thought patterns can assist in identification of individuals least likely to comply and achieve successful, healthy weight loss. Consistent, long-term follow up is also essential to minimize both medical and behavioral complications.

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