Lymphedema in the Morbidly Obese Patient: Unique Challenges in a Unique Population
In the majority of US states, 20% to 24% of the population – approximately 40 million individuals – is considered obese (20% over the ideal body weight).1 Morbid obesity is defined as weighing >100 lb more than ideal body weight or having a body mass index (BMI) of >40; its prevalence increased from 2.9% in 1988 to 1994 to 4.7% in 1999 to 2000.2
The healthcare costs for morbidly obese patients are nearly double those of normal weight patients due to the additional costs of obesity-linked chronic health conditions, such as diabetes, hypertension, and cardiovascular disease.3 Moreover, results from Fontaine et al’s4 epidemiological research study using National Health and Nutrition Examination Survey I and II cohort data (N = 14,407 and 9,282, respectively) show that morbidly obese Caucasian men and women ages 20 to 30 years are estimated to lose 13 and 8 years, respectively, from their life expectancies. For young African American men, this figure is even higher at 20 years. Conservative estimates based on two prospective studies5,6 of morbidly obese bariatric surgery candidates and a comparative retrospective study7 approximate that 75% of morbidly obese people have at least one comorbid condition that may explain the observed risk of premature death.
Lymphedema is one comorbid condition that has not been studied extensively in morbidly obese patients. In general populations, lymphedema is a relatively rare and serious disorder of the lymphatic system with a reported crude prevalence rate of 0.13%8 that tends to be associated with older female patients. However, information from wound clinic data submitted through the Intellicure (The Woodlands, TX) Research Consortium (IRC), a repository of de-identified electronic medical records (EMR) of approximately 15,000 patients from 17 wound centers in both urban and rural areas of 18 US states, show a 74% crude prevalence of lymphedema in morbidly obese patients. This is a very high prevalence rate compared to the reported rate in the general population. The prevalence of lymphedema among morbidly obese people has been referred to by some lymphologists as an “epidemic hidden in plain sight.” The purpose of this article is to educate clinicians regarding the features and treatment of lymphedema in the context of the morbidly obese.
To determine the accuracy of the authors’ clinical perception that the actual weight of lymphedema patients had increased over the years, a total of 1,463 electronic patient records from 2000 to 2005 were analyzed. Data were available for 575 men (39.2%) and 889 women (60.8%) with lymphedema. Without corresponding height data, BMI cannot be determined; however, by evaluating only patients (all races) weighing more than 350 lb, a trend toward increasing weight among patients presenting for treatment was noted during the 5-year period surveyed (see Figure 1).
Edema and Obesity
Because the body’s rich capillary network is designed to be “leaky,” filtered capillary fluid can remove the waste products of the extracellular space due to the slight pressure imbalance resulting from Starling forces, as long as the lymphatic system functions normally. At least 8 liters of lymph containing approximately 240 g of protein9 is collected from the extracellular spaces and carried back to the heart each day.10,11 The lymphangions propel lymph fluid via an intrinsic, unidirectional, pulsatile pumping action. Thus, the lymphatic system represents an alternative circulatory system, a kind of “storm sewer” system for the tissues, which generally receives little consideration until it is unable to manage the volume of fluid with which it is presented. Like domestic drainage systems, overflow can be caused by obstruction in the movement of normal volumes of fluid (mechanical insufficiency) or by excessive volumes of fluid that exceed the system’s transport capacity. Examples of the latter include congestive heart failure, hepatic failure, and hypoproteinemia due to chronic renal insufficiency or ascites (see Figure 2).10 When overflow occurs, fluid accumulates in the superficial tissues, usually resulting in bilateral leg swelling (see Figure 3). Increased capillary filtration results in low-viscosity, protein-poor interstitial fluid (pitting edema); lymphatic dysfunction produces a protein-rich fluid, initiating a cascade of inflammation that leads to dramatic changes in the skin and subcutaneous tissue.12 An additional consideration is venous insufficiency (VI), characterized by hemosiderin staining due to the deposition of iron oxide from extravasation of red blood cells into the tissues from venous hypertension. Over time, the inflammation associated with VI can lead to secondary lymphedema (see Figure 4). Morbidly obese patients are commonly observed to have both VI and lymphedema.13
Lymphedema is diagnosed as primary or secondary on the basis of etiology.14 Primary lymphedema affects a small minority of patients born with defects in the lymph-conducting pathways (see Figure 5). The estimated incidence of primary lymphedema in the US is one in 6,000 or approximately 50,000 individuals.15 Secondary lymphedema results from extrinsic damage or obstruction of the lymphatics. The most common examples of secondary lymphedema include filiariasis, a major problem in some developing countries (geographically associated with the life cycle of its mosquito vector), and arm lymphedema that results from trauma induced by axillary dissection or radiation therapy associated with breast cancer surgery.
Differential Diagnosis: Lymphedema and Lipedema
Lymphedema. During the initial presentation, lymphedema and lipedema may be confused because both present with the appearance of additional girth in the lower body. The best screening tool is a thorough medical, social, and family history including the clinical course of edema onset in relation to medications and/or other medical problems. Because many morbidly obese patients have low exercise tolerance and many are not able to lay supine for non-cardiac reasons, differentiating cardiac disease from non-cardiac factors can be challenging. Physical examination should include determining edema sites (eg, abdomen, hands and face), the presence of ascites or jaundice, and features of myxedema (eg, hair loss, pale mucus membranes, or heart murmur). Paradoxically, morbidly obese individuals can be malnourished and more prone to unhealthy forms of dieting than normal weight individuals.16 Laboratory testing should be based on the history and physical examination and can include a serum creatinine, albumin, electrolytes, thyroid panel, liver functions, or complete blood count. In patients whose physical findings or history are suggestive of cardiac disease, an echocardiogram should be obtained to assess the cardiac ejection fraction before initiating compression bandaging to ensure the heart is able to tolerate the increased work load of fluid mobilized from the legs.
Ironically, overuse of diuretics also can worsen lymphedema.17,18 As the patient becomes dehydrated, tissue osmolality increases, resulting in the extravascular movement of fluid into the tissue compartment. Patients for whom diuretics are prescribed to control hypertension do not need to discontinue this medication; however, patients who have been prescribed diuretics solely for the purpose of edema reduction almost universally report this treatment is ineffective and will likely feel better after diuretics are discontinued once appropriate compression measures are initiated.17,18
Primary lymphedema should be suspected any time a patient presents with chronic unilateral extremity swelling – ie, edema that does not improve with bedrest. A medical history also will provide a number of clues. For example, primary lymphedema is typically identified during one of three timeframes: at birth (congenital), in later adolescence (16 to 18 years of age; lymphedema praecox), or at about age 35 years (lymphedema tarda). If the patient has ipsilateral arm edema and a history of breast cancer treatment (surgery or radiation therapy), secondary lymphedema is likely the cause.19,20
Features. Skin inflammation, a basic feature of lymphedema, can cause chronic pain, functional impairment, and recurrent cellulitis. The diagnosis of lymphedema in the lower extremities starts with the appearance of “Stemmer’s Sign” – the inability to pinch a fold of skin at the base of the toes (see Figure 6a,b).10 The dorsum of the foot also can appear squared-off. Dermal changes that follow include dry or flaky skin, hyperkeratosis, skin creases, fibromas, lymphangiomas, and papillomas (see Figures 7 to 10); these will be evident on physical examination when lymphedema is more advanced. Extreme lymphedema manifests as elephantiasis. The International Society of Lymphology21 has determined three stages of lymphedema: Stage I represents a reversible condition (mild, pitting edema), Stage II introduces fibrotic conditions (pitting often stops), and Stage III involves elephantiasis. Confirmation of lymphedema is best obtained through MRI, which is considered superior to CT,12 or through lymphoscinctigraphy. Differentiating chronic VI from lymphedema via lymphoscinctigraphy is not always possible in the early stages because the former can cause the latter and will show unusually delayed lymph drainage;22,23 hence, quantitative lymphoscinctigraphy, which involves measurement of radiotracer accumulation in regional lymph nodes, is a viable option.24
Lipedema. Lipedema, a syndrome often mistaken for lymphedema,25 is a genetically mediated disease that involves the pathological accumulation of fat on the lower body. It is most commonly seen in women. One of the most definitive features is that the feet initially are spared – leg enlargement affects the ankle and lower leg in a “pantaloon” distribution (see Figure 11); whereas, in (primary) lymphedema, the feet are commonly the first area affected (ie, the “Stemmer’s Sign”). Furthermore, in lipedema, both legs are symmetrically affected. In later life, fatty depositions can occlude the lymphatic system, which can lead to secondary lymphedema; this “lipolymphedema” is apparent in Figure 7. In later life, morbidly obese patients who may have had only lipedema can develop secondary lymphedema and other complications such as recurrent cellulitis (which further worsens lymphatic obstruction) or heart failure with volume overload (due to sleep apnea from obesity). Late in life, when many sequelae of obesity have presented, determining whether edema problems began with primary or secondary lymphatic malfunction is almost impossible (see Figure 7).
The typical appearance of various edema syndromes (primary lymphedema, secondary lipolymphedema, venous insufficiency, and edema due to heart or renal failure – see Table 1) – are illustrated in Figures 3, 4, 5, 7, and 11. Common causes of chronic, bilateral edema include heart failure, renal insufficiency, hypoalbuminemia (which can be due to a protein-losing enteropathy, malabsorption, or malnutrition), myxedema, abdominal tumors, liver failure, or various drugs.12
Although a person with primary lymphedema also may be obese, lymphedema in most morbidly obese patients is due to the obesity. Whether lymphedema results from chronic VI (secondary lymphedema), a form of lipolymphedema, other obesity complications such as congestive heart failure (CHF), immobility, the loss of the calf muscle pump, associated sleep apnea, obstruction from overhanging pannus, or all of these factors, the fact is that obesity-related lymphedema is a direct result of the obesity and cannot be addressed separately. Equally as important, the clinician must ensure that neither the lymphedema nor the weight problems are due to undiagnosed conditions such as thyroid disease.26
Unique Obesity-Related Problems
Massive localized lymphedema (MLL) is an extreme example of the subcutaneous fat deposits pathognomonic of lymphedema. Although the literature27 describes MLL as “rare,” it is a common occurrence among morbidly obese individuals with lymphedema in the authors’ clinic. Massive localized lymphedema is characterized by a benign overgrowth of lymphoproliferative tissue, composed of fibrotic and edematous fibroadipose tissue.27 Due to its large size and similarity to sarcoma, this tissue mass often is termed a pseudosarcoma.28 These massive overgrowths commonly involve the thigh, popliteal fossa, scrotum, suprapubic and inguinal regions, and abdomen (see Figures 8, 9, 12). Histologically, the overgrowths exhibit vascular ectasia, mononuclear cell infiltrates, fibrosis, edema between collagen fibers, and ischemic changes, such as infarction and fat necrosis.26 In the authors’ experience, patients with this condition seek treatment when the size of the tissue mass starts to interfere with their daily activities or when excoriation or skin breakdown occurs. Skin changes are inevitable with lymphedematous conditions because macrophages acquire adipose tissue, causing permanent deposits of subcutaneous fat. Although usually seen on the lower extremities, skin changes also can occur in an overhanging abdominal pannus, giving rise to abdominal lymphedema (see Figures 9 and 10) and sometimes chronic, draining abdominal wounds. In such dramatic cases, surgery to remove the entire pannus or MLL is necessary. However, persistent edema and patient issues limit surgical success.
Initial Treatment of Lymphedema
An aggressive and coordinated regimen (commonly called complete decongestive therapy [CDT)]29) of manual lymph drainage (MLD), compression bandaging, and skin care is required to reduce the volume of the affected extremities to a near normal level. This is an internationally recognized standard of care for lymphedema treatment18 that is also successful for lymphedema arising from breast cancer treatment.30
Rather than long stretch bandages (eg, Ace wraps or cohesive bandages), CDT utilizes washable, reusable cotton bandages that provide little elasticity when maximum tension is applied. This feature permits the bandage to act as a resistive shell against which muscles can contract, giving rise to the high working but low resting pressure concept.31 Layers of foam and viscose-cotton or polyester padding are applied to protect bony protuberances and skin under the bandages.32 Wrapped in a distal to proximal gradient33 and worn continually in the initial stages, compression bandaging for lymphedema often extends from the toes to the groin in the lower extremities and from the fingers to the axillae for arm bandages.34 Such wrapping is far more extensive than the compression bandaging used in venous disease.
Although compression garments constitute the mainstay lymphedema treatment, most obese patients with lymphedema are not able to wear garments due to limb distortion and abdominal girth that prohibits use of such garments. However, semirigid devices, such as the Circaid™ (CircAid Medical Products Inc, San Diego, Calif), Armassist or Legassist™ (Compression Design, Zeeland, Mich), or Farrow wrap (Farrow Medical Innovations, Bryan, Tex) can be useful in the morbidly obese (see Figures 12 and 13). Medicare does not cover garments for patients who do not have wounds so any type of garment or device for lymphedema management is non-reimbursable for Medicare beneficiaries. Other payors have covered this important equipment if clinicians write letters of medical necessity.
Lymphedema and Wound Healing
In general, wounds are managed by controlling bioburden, debriding nonviable tissue, and managing drainage. Similar to VI,35 wounds usually are not likely to heal if the edema is not controlled but controlling edema is challenging. Serious regional oxygen deficiency followed by reperfusion periods can occur in lymphedematous tissue36 as well as in ulcerated edematous limbs37 but it is not clear whether the reduced oxygen levels are entirely responsible for the compromised wound healing in this situation or to what extent the amount of edema present influences the course of events.
Integrating compression into wound management requires careful planning. Dressings must be chosen according to their performance under sustained compression (ie, preventing rubbing, irritation, or leaving marks on the skin) and whether they have sufficient absorptive properties, odor control, and other practical attributes, including cost.
Skin Care and Wound Prevention
Skin care and prevention of even minor tissue trauma must be emphasized. The National Lymphedema Network38 recommends several practices to reduce the risk of infection and skin breakdown. First, the skin must be kept clean, dry, and moisturized to prevent chaffing. Low-pH moisturizers can be used to reduce microbial growth.39 Next, protective clothing such as gloves should be worn while engaging in activities that might cause skin injury; likewise, insect repellent to prevent insect bites and sunscreen to prevent sunburn are prudent precautions. Razors should be used carefully to prevent nicks and cuts to the skin and injections or blood tests should be minimized to reduce the number of occasions for opportunistic infection. Finally, if a cut or skin puncture occurs, the wound should be carefully cleansed and antibiotic cream applied. Patients also are advised to contact their primary care healthcare provider if obvious signs of infection (eg, rashes, itching, redness, increased skin temperature, or fever) occur.
For patients with more advanced lymphedema who exhibit fissured, keratinified skin, lactic acid products can be helpful in addressing desquamation and Olivamine™-containing formulations (eg, Remedy Skin Care, Medline Industries, Inc., Mundelein, IL) can help reduce superficial inflammation.
Obesity is implicated in a wide spectrum of dermatological diseases, including acanthosis nigricans, acrochordons, keratosis pilaris, striae distensae, adiposis dolorosa, plantar hyperkeratosis, skin tags, and candidal intertrigo.40,41 Therefore, morbidly obese patients who also have lymphedema are at risk for additional skin disorders. The authors have found that a new product, Interdry Ag+ (Coloplast, Minneapolis, MN), a fabric that wicks away moisture and reduces bioburden, may be useful in patients with multiple, redundant skin folds.
Lymphedema Therapy and Equipment Challenges
Exercise. Exercise is a lynchpin of edema treatment42 but because morbidly obese patients have ambulation problems, their ability to exercise is limited. Moreover, such patients frequently become dependent on electronic transport devices. While providing them with increased social opportunities, these devices can worsen their condition by making ambulation unnecessary.
Transfer. Patients with morbid obesity also have serious transfer problems.43 A treatment table obtained by the authors was certified to sustain high weight but required three therapists to counterbalance large patients ascending the table in order to prevent it from tipping over. Thus, selecting equipment only on the basis of weight-bearing capability can be inadequate when attempting to provide a safe environment for patients (see Figure 14).
Position. Morbidly obese patients may be unable to lay supine. Sometimes, this may be due to CHF but more commonly relative to obstructive apnea, severely limiting the benefits of MLD. Some patients can be so short of breath due to cardiac or respiratory factors that MLD therapy is not safe.
Compression application. The physical challenges of applying compression bandages to large patients are well known to therapists. Often, two or three awkwardly positioned therapists are required to accommodate the mobility limitations of obese patients (see Figure 15) and the required additional bandaging materials and more staff time cannot be recouped by increasing billed charges. Even if compression bandaging can be applied, the application process might well be futile, because the lack of movement does not provide the necessary “muscle-pump” activity for certain bandages to work properly.44
Equipment. Ten years ago, no patients >500 lb came to the authors’ clinic for treatment. Now, seeing 500- or 600-lb patients is not uncommon. Waiting room furniture at the authors’ clinic is now wider and sturdier and chairs without armrests have been added. In addition, special scales that can weigh patients up to 800 lb and are wide enough to allow patients to stabilize themselves on the scale were purchased.
Patients who do not have their own transport devices usually cannot be safely accommodated in wheelchairs that are pushed manually. After the wheels on an extra-wide manual chair collapsed while in use by a large patient and subsequent to a petite transportation technician losing control of a heavy patient on a descending ramp, the authors’ clinic purchased an electronic, extra-wide wheelchair that is rated to 750 lb and operated by a toggle switch in the back. This chair cost in excess of $10,000 in 1998; at the time, the purchase was controversial. Administrators questioned the need to allocate a substantial percentage of the equipment budget for a “transportation device.” Now in its tenth year of use, the chair is in constant demand by departments all over the hospital.
Extra-wide potty chairs, bariatric hospital beds, lifting chairs, and other equipment that might be needed for obese patients represent an increasing proportion of hospital budgets across the country. These costs are usually not borne by third-party payors. Nevertheless, patients expect facilities to be prepared to meet their needs. A patient comment from one of the authors’ clinic feedback cards sums up the problem: “Don’t you know that the number of overweight people is on the rise and the need is here now to help us?”
Memorial Hermann Guidelines for Participation in the MLD Program
Many obese patients can participate and benefit from lymphedema therapy. However, the authors found the need to establish consistent criteria to ensure consistency and patient and staff safety. The program criteria for MLD therapy include these patient requirements:
1. Absence of diseases that affect the safety of MLD
2. Must be able to safely and with minimal assistance transfer on and off the MLD table
3. Patient weight cannot exceed MLD table weight limit
4. Must be ambulatory, even if minimally
5. Must not have a BMI >70 (eg, 5'2” woman weighing 380 lb)
6. Must commit to maintaining a constant weight, or preferably losing weight, during the course of treatment.
Bariatric surgery has been shown to have many beneficial and even life-saving results among the morbidly obese. Long-term follow-up studies45-51 of bariatric surgery involving morbidly obese patients have started to appear in the literature and the results are illuminating. The procedures require that patients follow a detailed set of guidelines in order for weight loss to be successful; postoperative complications can occur.46,47 Increasingly, bariatric surgery programs include counseling48-50 in order to moderate the potentially unrealistic expectations and anxiety found to be associated with the significant issue of non-adherence to guidelines.51
What is most interesting is that adherence to follow-up in a series of cognitive behavioral therapy programs designed to treat obesity was found to be inversely proportional to the severity of the obesity.52 These results mirror the authors’ experience. The psychosocial factors that interact to produce a morbidly obese individual are complex and poorly understood but clearly affect participation in, and benefits derived from, lymphedema treatment. In the authors’ experience, patients who gain weight respond poorly to edema treatment; conversely, patients who maintain or lose weight achieve benefit. Although they should occur concurrently, specific counseling programs are not offered at the authors’ facility; instead, patients “contract” for continued care by exhibiting positive behaviors regarding weight loss, attendance at bariatric support groups, Weight Watchers®, or other beneficial practices. Morbidly obese patients who ignore the condition that predisposed them toward lymphedema are unlikely to have a good prognosis with lymphedema treatment.
Based on clinician observation and experience, management of the morbidly obese patient with lymphedema requires that the obesity be addressed in a frank and supportive way. Many morbidly obese patients exhibit a strong element of denial regarding the disease of obesity. Obtaining treatment for obesity is a life-or-death decision but patients often focus more on the treatment of an obesity symptom – ie, edema – than the underlying problem that will shorten their life.3 Treatment of lymphedema must be linked to the treatment of obesity if long-term success is to be achieved. When the clinician and patient develop a collaborative approach to care, lymphedema in morbidly obese patients can be managed with good results (see Figure 16 a,b).