The "Nine Ds" of Determining the Cause of Weight Loss in the Elderly

David M. Kaplan, MScHA

Weight loss in the elderly should always be a great concern for the clinician because it can be an indicator of malnutrition. Involuntary weight loss has been shown to be highly predictive of morbidity and mortality.¹ All physicians who treat geriatric patients need to have a framework for identifying and evaluating weight loss in this patient population. One Canadian study found that 40% of elderly persons receiving home care services reported involuntary weight loss over a period of one year.² This practical approach to involuntary weight loss in the elderly will begin with a definition and then present a simple and organized approach to diagnosis and evaluation.

Definition and Risk Factors
Weight loss in the elderly becomes worrisome when the patient has involuntarily lost five percent of their body weight over a six-month period.³ Social Isolation has been identified as a risk factor for weight loss. While the mechanisms are not clearly understood, it is thought that poor physical functioning may be linked to a decrease in social support.⁴ Social isolation has been demonstrated to be detrimental to health and health outcomes.^3,4,5 Sensory decline, poor oral hygiene, disease, polypharmacy, drug-nutrient interactions, poverty, and alcohol abuse have been found to be risk factors for involuntary weight loss in the geriatric population.

Approach to Weight Loss
Before the clinician adopts an approach to determine the cause of weight loss in a specific patient, she must first be astute enough to perceive a problem. Recognizing weight loss in the elderly can often be problematic. Our pediatric colleagues place great importance on following and charting weight and height parameters in all their patients. It is best to follow their example in this regard. Geriatricians, family physicians, and other primary care providers should, at the very least, record the patient's weight and height at every visit. By adopting this practice ritual, they will become aware of subtle weight loss in their elderly patients.

Once established, involuntary weight loss can be handled by utilizing a broad-approach differential diagnosis. Bianchi divides weight loss into three possible, but not mutually exclusive, etiologies.⁵ Of the three basic causes of weight loss, decreased intake (table 1) is the most common in the elderly. The second cause, increased fluid-nutrient loss (table 2), is caused predominantly by malabsorptive disorders and by diabetes. Lastly, states of excess metabolic demand (table 3) resulting from gastrointestinal, genitourinary and breast carcinomas are also a basic cause of weight loss.

TABLE 1 CAUSES OF DECREASED FOOD INTAKE LEADING TO INVOLUNTARY WEIGHT LOSS
Mechanism of weight loss	Example
Disease Gastrointestinal Malignancy Eating Disorders Infection Systemic diseases	Peptic Ulcer, Cholelithiasis GI, Ovarian Anorexia, Bulimia Nervosa HIV
Depression Dysphagia Dysgeusia Dentition Dysfunction Dementia	Primary illness or concurrent with failing medical condition May be caused by disease May be caused by disease Poor Dentition Primary illness
Drugs Substance Abuse Medications	Alcohol Beta-blockers Anticholinergics Benzodiazepines Neuroleptics SSRIs Tricyclic antidepressants
Poverty	Unable to afford food
Social Isolation	Multiple mechanisms

A second, and perhaps, more practical approach to a differential diagnosis of weight loss in this specific population, is the "Nine Ds of weight loss in the elderly."⁷ Robbins first identifies whether the cause of weight loss is due to acute or chronic disease. The different diseases that lead to weight loss have been discussed above and in the accompanying tables. Depression has also been implicated in weight loss and health outcomes. Depression is linked to social isolation and, therefore, depression affects health outcomes.^3,5 Depression in the elderly is correlated to lower socioeconomic status, female gender, older age, martial status, frequency of visits to physicians, lower functional status, and poor self-reported health.^5,7 Clinicians must realize that these patients often present with physical, rather than emotional, complaints.⁴ While it is the most common psychiatric illness in this population, it is under-diagnosed and under-treated.

Diarrhea, dysphagia, dysgeusia (impaired taste), and abnormal dentition are obvious causes of weight loss in any population and must be kept in mind while examining the patient. Numerous studies have linked dementia to weight loss in the elderly.⁴ One of the outcomes of dementia, dysfunction (problems in physical, cognitive and psychosocial function), is itself an independent cause.4 Food shopping, and the preparation and eating of food are integral parts of our daily life. And yet, Markson reports that 23% of older people in the community have health-related difficulties with activities of daily living (ADLs) such as bathing, dressing, feeding, and using the bathroom.⁸ Moreover, 28% of the same population has difficulties with independent activities of daily living (IADL) (using the telephone, shopping, banking, laundry, and transportation).⁸ Clearly, patients who have had a decline in their functional ability are at risk for involuntary weight loss.

Whether due to a single pharmaceutical agent or to polypharmacy, drugs can also cause weight loss in the elderly.⁴ Beta-blockers and anticholinergic agents cause cognitive changes, which lead to functional decline. Narcotics, benzodiazepines, neuroleptics, and selective serotonin reuptake inhibitors (SSRIs) can produce anorexia. Lastly, use of tricyclic antidepressants to treat depression can cause dysgeusia and dry mouth. Now that a general approach to diagnosing the cause of weight loss in the elderly patient has been described, we can begin to illustrate a more individualized approach to a particular patient in the office.

TABLE 2 CAUSES OF INCREASED FLUID/NUTRIENT LOSS LEADING TO INVOLUNTARY WEIGHT LOSS
Mechanism of weight loss	Example
Disease Malabsorption Recurrent vomiting Fistulous drainage Pancreatic	Celiac disease
Insufficiency Infection Inflammatory bowel disease	Giardiasis Crohn's disease
Drugs Medications	Cholestyramine, laxatives

The Patient Encounter
The medical interview is fundamental to the patient encounter. The best method of initiating an investigation of a patient who has had clinically noted weight loss is to take a complete history. Specifically, one should focus on determining the following: First, what is the patient's daily oral intake; secondly, are there symptoms characteristic of malabsorptive conditions or malignancy; thirdly, is there a history of heart, lung, or kidney failure. As explicated previously, a depression-screening exam may also be beneficial in the work-up of a patient with involuntary weight loss. As is usually the case, one should conclude the history with a complete review of systems to elicit whether the patient may be having any additional symptoms.

The physical exam is guided by what one uncovers during the interview. While working up these patients from a general standpoint, the physical exam should include the measurement of vital signs, the patient's weight and height, and a calculated body-mass index (BMI: weight(kg)/height (m)²). Healthy, elderly people should have stable weights and a BMI higher than 23 kg/m². One should look for evidence of dementia by doing cognitive tests such as repeated Folstein Mini-Mental State Examinations. The presence of lymph nodes, evidence of previous chest or abdominal surgery, abdominal masses, abdominal distention, ascites, or organomegaly should be noted. A digital rectal exam should also be performed along with fecal occult blood testing. Next, a full musculoskeletal exam should be conducted to observe evidence of osteoarthritis, which could be affecting the patient's ADLs and IADLs. Lastly, a screening neurological exam should be done to elicit any focal neurological lesions.

Armed with the data from the complete, focused history and physical, the basic laboratory screening tests may include a complete blood count, electrolytes, blood glucose, urinalysis, liver and renal function tests, calcium, thyroid function, hemoccult stool tests, and a chest radiograph. The special tests, which may be necessary based on history and physical exam findings include: ESR, HIV test, blood cultures, upper GI series, esophagealgastroduodenoscopy, and colonoscopy.^3,7 A CT scan or ultrasound study may be indicated to investigate abdominal masses or abscesses.

TABLE 3 CAUSES OF EXCESS METABOLIC DEMAND LEADING TO INVOLUNTARY WEIGHT LOSS
Mechanism of weight loss	Example
Disease Hyperthyroidism Tumour of adrenal gland Malignancy Fever/infection Systemic disease	Pheochromocytoma Disseminated metastatic Malaria, TB, HIV
Depression/dementia and other psychiatric disorders Trauma Excessive exercise	Mania Burns

Treatment
While the purpose of this article was to elucidate an approach to the patient who presents with involuntary weight loss, the final section will briefly describe the general management of these patients. If the results of the basic screening do not reveal an underlying disease, a waiting period to see how the patient fares would be prudent; serious disease will likely, if present, reveal itself within half a year.³ Once the cause of the weight loss is evident, treatment is based on the underlying medical or psychological conditions. One should continue to monitor height and weight throughout the course of treatment. A reassessment of the patient's medications is also warranted. Finally, the proper use of community resources (Meals on Wheels, Assisted living, nursing homes), a dietician, social worker, and an occupational therapist should also comprise part of a comprehensive treatment plan for these patients.

Summary
Involuntary weight loss, defined as a five percent of body weight reduction over a six-month period, has been shown to be a cause of poor health outcomes in the elderly patient. This approach highlighted the necessity for clinicians to be cognizant of the many etiologies of weight loss in this population. A good history and physical followed by appropriate laboratory tests is necessary in order to diagnose and successfully develop a comprehensive treatment plan.

References

1. Wallace, JI, Schwartz RS. Involuntary Weight Loss in Elderly Outpatients: Recognition, Etiologies, and Treatment. Clinics in Geriatric Medicine: Failure to Thrive in Older People 1997;13(4):717-736.
2. Payette H, Gray-Donald K. Risk of malnutrition in an elderly population receiving home care services. Facts and Research in Gerontology 1994;2(suppl):71-85.
3. Verdery RB. Clinical evaluation of Failure to Thrive in Older People. Clinics in Geriatric Medicine: Failure to Thrive in Older People 1997;13(4):717-736.
4. Markson, EW. Functional, Social, and Psychological Disability as Causes of Loss of Weight and Independence in Older Community-Living People. Clinics in Geriatric Medicine: Failure to Thrive in Older People 1997;13(4):717-736.
5. Berkman LF, Berkman CS, Kasl S et al. Depressive symptoms in relation to physical health and functioning in the elderly. Am J Epidemiol 1986;124:372-388.
6. Bianchi A, Toy EC, Baker B III. "The Evaluation of involuntary weight loss." Primary Care Update Ob/Gyns 1998; 5:263-267.
7. Robbins LJ. Evaluation of weight loss in the elderly. Geriatrics 1989;44:31-37.
8. American Association of Retired Persons and Administration on Aging, U.S. Department of Health and Human Services: A Profile of Older Americans, 1996. Washington, DC, Program Resource Department, American Association of Retired Persons, 1996.

Lilia Malkin, BSc

Nutritional status has been widely acknowledged to play a key role in the maintenance of health and recovery from disease. Malnutrition has been linked to increased morbidity and mortality, while nutritional support through enteral or parenteral routes has been demonstrated to contribute to reduced morbidity and shorter hospital stays.¹ It is also recognized that while several vitamins and minerals are essential to the human body, nutrient intake requirements do vary across age groups. Unfortunately, it may be difficult to obtain the necessary nutrients from food products alone. The challenge of maintaining a well-balanced diet with appropriate caloric and nutritional intake is made more difficult in the ill and the elderly, resulting in malnutrition. This article will focus on the unique nutrient requirements of the geriatric population and the potential contribution of oral nutritional supplements in ensuring a well-balanced diet among both community-dwelling and hospitalized members of this age group.

Nutrient requirements
As the body grows older, it undergoes a multitude of physiologic alterations, resulting in changes in macro- and micro-nutrient requirements.

Nariman Malik, BSc

Diverticular disease of the colon had been a rare clinical entity before the twentieth century. Currently, diverticulosis is the most common condition affecting the intestine.¹ The incidence of diverticular disease increases with age from approximately 9% in those younger than 50 to 50% in those over the age of 70.² Diverticular disease is almost exclusively seen in populations that consume low fibre diets such as those common in Western society. Interestingly, these conditions are less common in vegetarians than in non-vegetarians. There is no associated risk with smoking, caffeine, or alcohol use.³

A diverticulum is defined as a sac-like protrusion of the colonic wall. Colonic diverticuli are formed by the herniation of the mucosa and submucosa through the muscularis mucosa. They tend to develop at points where the vasa recta penetrates the circular muscle layer.

Diverticular disease is a spectrum of diseases that encompass three clinical multi-faceted conditions: diverticulosis, diverticulitis, and diverticular bleeding. Each condition has a unique set of presenting symptoms and an individualized course of management (see Table 1).

Alexandra Nevin, BSc

Gastroesophageal Reflux Disease (GERD) is the pathological manifestation of a normal physiological process, and is associated with a range of clinical symptoms and complications of varying severity. In normal individuals, gastric acid reflux into the esophagus occurs without any accompanying signs or symptoms of mucosal damage. The majority of these events are the result of transient lower esophageal sphincter relaxation (TLESR).^1,2 Normally, TLESR is not accompanied by inadequate innate esophageal protective mechanisms which characterize the development of GERD. The wide spectrum of presenting symptoms makes definitive and accurate diagnosis and management of GERD a clinical challenge. This is especially true for physicians who treat the elderly and have to contend with the increased absolute incidence of GERD, the number of concurrent medical conditions, changing physiology of the aging esophagus, and the prevalence of atypical symptoms and complications.

The incidence and natural history of GERD
In the United States, 44% of the adult population surveyed reported experiencing heart burn, the most frequently noted symptom of GERD sufferers, at least once every month.^3,4 The absolute incidence of GERD has been shown to increase with age, with an initial dramatic rise in incidence after 40 years of age, and significant increases at age 60 and then again at age 70.

Normal Function is Retained Despite Age-related Changes

J. Sedmihradsky, BSc, MA

Introduction
Although failing gastrointestinal function may have been previously associated with advancing age, this is not currently the case. In recent years, clinical studies have changed perceptions about how the gastrointestinal tract ages, demonstrating that in general, normal gastrointestinal function is retained in healthy elderly individuals. This article will discuss the age-related changes that can occur in the gastrointestinal system of the elderly.

Overall, the gastrointestinal tract does not undergo major changes with the aging process. Consequently, the recommended dietary intake of nutrients for the elderly remains quite similar to that of younger adults.

A. Mark Clarfield, MD

Having spent several years as a family doctor before becoming a consultant geriatrician, I have stood on both sides of the fence. As a primary-care physician, I was subjected to the humiliations dished out by many a consultant. Yet, to my chagrin, in later years, I found myself perpetrating similar outrages on physicians seeking my help.

As patients, the elderly are particularly vulnerable to getting caught in the crossfire when consultant and consultee do not see eye to eye. The main reason for this is that no one needs the services of good primary care with appropriate consultant backup more than the older patient.

In this article as well as in the March issue, I shall describe mistakes that I have made (or seen colleagues make) on both sides of the great divide between consultant and consultee.

Sins of the Consultant

1. Arrogance: Chapter 1

The specialist has, by definition, a very comprehensive knowledge of a specific area of medicine. This knowledge can be used to beat the consultee over the head with implied or overt criticism.

Philip Dopp, BSc

Alzheimer's Disease (AD) is a neurological disorder that is characterized by a slowly degenerative process affecting cognitive function. At a histopathological level, AD patients are characterized by the deposition of senile plaques within the brain, as well as within the walls of cerebral blood vessels.^1-5 It is believed that through an unknown mechanism, these senile plaques exert a toxic effect on surrounding neurons, resulting in the neuronal degeneration found in AD patients.^1,5

The primary constituent of these senile plaques is amyloid b peptide (Ab). Two proteases, b-secretase and g-secretase cleave this peptide from a larger precursor protein, b-amyloid precursor protein (APP).^1,5-6 Essentially, b-secretase cleaves APP to produce an APPsb soluble fragment and C99, a membrane bound fragment, whereas a-secretase can prohibit Ab formation by cleaving APP within the Ab sequence to produce APPsa and C83.⁶ Ultimately, g-secretase acts on C99 to produce Ab, or on C83 to produce a nonpathogenic p3 peptide.

Anna Liachenko, BSc, MSc

Canadian postmenopausal women now have a new drug option for treatment of established osteoporosis and/or relief of pain associated with osteoporotic fractures--synthetic salmon calcitonin administered as a nasal spray (Miacalcin Nasal Spray or Miacalcin NS). Already available in over 70 countries, the drug was approved in Canada in September of 1999. The nasal spray is very safe and has been shown in various studies to increase bone mineral density (BMD) in vertebrae, the primary site of fractures in postmenopausal osteoporosis. Several months ago a large clinical trial confirmed that Miacalcin NS lowers the risk of vertebral fractures, making it an important agent for osteoporotic therapy.⁶

Calcitonin is a peptide hormone secreted by the thyroid gland and its secretion is under the direct control of blood calcium levels. In humans, no definite effects on calcium levels are seen in states of calcitonin deficiency or excess. Calcitonin was discovered over 35 years ago by Dr. Harold Copp at the University of British Columbia. Secretion calcitonin is estrogen-dependent and is decreased after menopause.^7,8 Osteoporotics have lower levels of serum calcitonin than both premenopausal and healthy menopausal females. It is likely that the deficiency in the hormone plays some role in postmenopausal bone loss, and studies have found that calcitonin counteracts both early and established osteoporosis.

Dr. Michael J. Taylor

The following article attempts to add insight into the complex and difficult issue of physician assisted suicide by approaching it from a broad perspective. The article will begin with a brief and informal historical survey of attitudes toward physician assisted suicide. It will then address the arguments both for and against this issue, and conclude with an examination of some of the evidence that is available to support concerns of those on both sides of the debate. Included in the article are some inferences as to the direction debates about physician assisted suicide might take in the future. Though terms such as euthanasia and physician assisted suicide are often used to denote different entities both by the lay public and within the medical literature, for the purposes of this article, the term physician assisted suicide is used to describe the active involvement of a physician in ending the life of a patient at the patients specific request (i.e. through the prescription or administration of lethal medications). The act of ending the life of a patient without his or her specific request (i.e. "mercy killing"), and the decision to forgo life sustaining treatment (including the use of ventilators, dialysis or feeding tubes) are not included within the definition of physician assisted suicide as discussed in this article.

Nariman Malik, BSc

Introduction
Mitral regurgitation is a common valvular heart disease, especially in the elderly.¹ It is defined as a condition in which there is an abnormal flow of blood from the left ventricle to the left atrium across an incompetent mitral valve during ventricular systole.² The mitral valve consists of four main components: the annulus, anterior and posterior leaflets, the chordae tendinae and the papillary muscles. Mitral regurgitation has a number of underlying etiologies that can be broadly classed into two groups: mitral regurgitation due to organic disease (e.g. rheumatic disease or infective endocarditis) or mitral regurgitation due to functional causes (regurgitation results from myocardial dysfunction as opposed to valvular problems). In developed countries, the etiologic profile of mitral regurgitation has changed over recent years due to the decreased incidence of rheumatic heart disease.³ Mitral regurgitation is most frequently due to degenerative and ischemic causes in the western world.⁴ See table 1

TABLE 1 ETIOLOGY

Mitral regurgitation is often classified by its underlying etiology.