ReviewRational Approach to Patients With Unintentional Weight Loss
Section snippets
PATHOPHYSIOLOGY OF WEIGHT LOSS
The precise mechanism of weight loss is unknown in many patients. Caloric intake, absorption, utilization, and loss are key components that determine an individual's weight. Alteration in the balance of these components affects a patient's ability to maintain weight. For example, caloric intake may be modified by altered smell or taste, anorexia, nausea, abnormal satiation, etc. Absorption may be modified by altered gastrointestinal motility, exocrine pancreatic function, mucosal absorptive
ETIOLOGIES OF WEIGHT LOSS
Whereas dieting and eating disorders (ie, anorexia nervosa and bulimia nervosa) explain most cases of intentional weight loss, unintentional weight loss can be divided into organic, psychosocial, and idiopathic etiologies. Additionally, selected groups (eg, older adults) often have multiple etiologies to explain their weight loss. Three studies that have evaluated the etiologies of unintentional weight loss, defined as more than 5% of usual body weight, are summarized in Table 1.17, 18, 19
EVALUATION OF UNINTENTIONAL WEIGHT LOSS
In most patients, the etiology of unintentional weight loss is identified through a detailed history and physical examination. Key concepts of the evaluation include: (1) document weight loss-in up to 50% of patients, weight loss cannot be documented13; (2) perform a detailed history-medical, psychosocial, and dietary-and physical examination; (3) perform tests based on history and physical findings in conjunction with limited standard tests; and (4) establish appropriate follow-up to assess
MANAGEMENT PRINCIPLES
Early intervention based on the findings of the diagnostic evaluation provides the greatest opportunity for success. The severity of weight loss should be determined by a nutritional assessment, including a biochemical analysis combined with a thorough dietary history, evaluation of the patient's psychosocial situation, and consideration of anthropometric or other qualitative evaluations. A simple and common anthropometric evaluation is the body mass index (BMI). The BMI is defined as body
SUMMARY
Body weight, as determined by several key components, remains relatively stable over time. Unintentional weight loss, defined as a decrease of more than 5% of usual body weight during a 6- to 12-month period, is an important predictor of morbidity and mortality. However, weight loss is a nonspecific finding with multiple possible etiologies, including organic, psychosocial, and idiopathic. A rational stepwise approach based on relevant data extracted from the history and physical examination,
REFERENCES (48)
Involuntary weight loss
Med Clin North Am
(1995)- et al.
Low body weight and weight loss in the aged
J Am Diet Assoc
(1990) - et al.
Anorexia in the elderly
Neurobiol Aging
(1988) - et al.
Clinical study of 105 cases of isolated weight loss in internal medicine [in French]
Rev Med Interne
(1988) Folate and cobalamin in psychiatric illness
Compr Psychiatry
(1997)B12 and folate deficiency dementia
Clin Geriatr Med
(1988)- et al.
Thiamin in the elderly-relation to alcoholism and to neurological degenerative disease
Am J Clin Nutr
(1982) - et al.
Rumination syndrome
Mayo Clin Proc
(1997) - et al.
Role of impaired gastric accommodation to a meal in functional dyspepsia
Gastroenterology
(1998) - et al.
“Mini-mental state:” a practical method for grading the cognitive state of patients for the clinician
J Psychiatr Res
(1975)
Development and validation of a geriatric depression screening scale: a preliminary report
J Psychiatr Res
A global perspective of home parenteral and enteral nutrition
Nutrition
Enteral nutrition
Gastroenterol Clin North Am
Descriptive epidemiology of body weight and weight change in U.S. adults
Ann Intern Med
Longitudinal physique changes among healthy white veterans at Boston
Hum Biol
Distributions of serial changes in stature and weight in a healthy elderly population
Hum Biol
Nutritional assessment
The Biology of Human Starvation
Body weight as a risk factor in the elderly
Arch Intern Med
The effect of age on the association between body-mass index and mortality
N Engl J Med
Weight loss and mortality among free-living frail elders: a prospective study
J Gerontol A Biol Sci Med Sci
Weight change and physical function in older women: findings from the Nun Study
J Am Geriatr Soc
Involuntary weight loss in older outpatients: incidence and clinical significance
J Am Geriatr Soc
Weight loss in nursing home patients: prognostic implications
J Fam Pract
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This work was presented in part at the Tenth Annual Advances and Controversies in Clinical Nutrition Course sponsored by Mayo Foundation and the American Society for Parenteral and Enteral Nutrition on April 28, 2000, in Tempe, Ariz.