July 2008 Issue

Malnutrition: A Serious Concern for Hospitalized Patients
By Theresa A. Fessler, MS, RD, CNSD
Today’s Dietitian
Vol. 10 No. 7 P. 44

The problem of malnutrition in hospitalized patients was revealed in a 1974 article, “The Skeleton in the Hospital Closet,” by Charles Butterworth, Jr, MD, and published in Nutrition Today. Citing several cases of neglect in nutrition care, Butterworth pointed out that changes in practice were urgently needed to properly diagnose and treat undernourished patients and prevent iatrogenic malnutrition.

Today, malnutrition in hospitals remains a serious issue. It occurs worldwide and affects patients of all ages—from infants in the neonatal intensive care unit (ICU) to geriatric patients.1-11 RDs have the ability to identify nutritional problems more readily than other healthcare professionals and are critical to the proper diagnosis, treatment, and prevention of malnutrition.

History and Scope of Malnutrition
Estimating the prevalence of hospital malnutrition is difficult. Over the past 34 years, researchers have used different criteria to define it, and studies have been conducted worldwide on populations that differ in socioeconomic status, educational level, age group, and severity of illness; study group size also varies. Based on many reports worldwide, an estimated 13% to 69% of hospitalized patients are malnourished.1-11 Malnutrition has been associated with an increased length of hospital stay, increased morbidity and mortality, impaired respiratory and cardiac function, decreased immune function, and poor growth in infants and children.2,5,7,9,12

In 1976, Bistrian and colleagues reported a 44% or greater prevalence of malnutrition in 251 hospitalized patients. Their criteria included less than or equal to 90% of standard for anthropometric measurements and low serum albumin and hematocrit levels. Twenty-three percent of the patients were underweight at less than or equal to 80% of standard.1

Weinsier et al assigned likelihood of malnutrition scores based on serum folate and vitamin C levels, anthropometric measurements, lymphocyte count, and hematocrit levels in 134 patients at a teaching hospital. At admission, the likelihood of malnutrition was 48% and was correlated with longer length of stay and increased mortality, with worsened nutritional status after two weeks of hospitalization.2 Twelve years later, the study was repeated with 228 patients at the same hospital with likelihood of malnutrition at 38%. It was still associated with a longer length of stay, but likelihood of malnutrition scores improved during hospitalization.3

Lymphocyte counts, hematocrit levels, and serum albumin levels were included in the criteria for malnutrition in some older studies, but these variables are not specific indicators of malnutrition and are affected by many conditions other than nutritional status.1-3,13-15 Recent accounts of hospital malnutrition use body mass index (BMI), subjective global assessment (SGA), or some components of SGA, such as weight loss and food intake.4-10,16

In 1994, McWhirter and Pennington reported that 40% of patients in a British hospital were malnourished at admission, and two thirds of all patients lost weight during hospitalization.4 Of 219 patients in an academic, inner-city hospital in the United Kingdom in 1998, 13% were malnourished based on BMI and weight loss; only seven of these patients were referred to the dietary department.5 In a recent British study of 2,283 patients, malnutrition was determined by weight loss, poor intake, wounds, and infection. Prevalence decreased from 23.5% in 1998 to 19.1% in 2003, and referrals to the dietetic department increased, after staff education and improved food quality.6

In a recent report of 740 patients in three hospitals in Denmark, 23% were determined to be at nutritional risk based on BMI, weight loss, oral intake, and disease severity; only 25% of those at-risk patients received adequate nutrition during hospitalization. Only 59% of the patients were screened at admission, and of those determined to be at risk, only 47% had a nutrition care plan, which led to a program for staff training on nutrition screening.7 Of 794 patients from two hospitals in Berlin, 22% were malnourished based on SGA, and malnutrition was associated with an age of 60 or older, living alone, a lower level of education, malignancy, and polypharmacy.8 In a recent multicenter study of 9,348 hospitalized adults in Latin America, 50% were determined to be malnourished based on SGA. Malnutrition was correlated with an age of 60 or older, cancer, infection, and increased length of stay.9

Nutrition Screening and Assessment
In the mid-1990s, The Joint Commission mandated that hospitals establish nutrition screening and assessment guidelines. Nutrition screening should occur within the first 24 hours of admission. Screening criteria usually include weight and height, recent weight change, oral intake, and sometimes diagnosis and/or other comorbidities.12,16 Screening is overlooked for some patients who have surgery within or soon after the first 24 hours of admission, so outpatient screening prior to surgical admissions may be beneficial.17

Any patient identified to be at risk should have a nutrition assessment, using information on weight and weight changes, food intake, gastrointestinal (GI) symptoms, functional capacity, disease state, physical characteristics, and symptoms of micronutrient deficiencies; for neonates and pediatric patients, birth weight and growth progress.12 Factors to address include calorie, protein, vitamin, mineral, electrolyte, and fluid needs and the route of nutrition support, if necessary.16 Laboratory tests for vitamin levels should be conducted for patients at risk for deficiencies. Patients with GI disorders and those on long-term parenteral nutrition (PN) are at risk for trace element deficiencies.18

Unintentional weight loss is used as a reliable indicator of malnutrition; however, weight can falsely elevate or decrease depending on hydration status, so clinicians should estimate euvolemic weight. Weight can increase due to edema, anasarca, and fluid resuscitation in the critically ill, as well as fluid retention in congestive heart failure and chronic hepatic and renal disease.

Clinicians have traditionally used hepatic proteins such as albumin, prealbumin, and transferrin as markers of nutrition status; however, they are now known to be negative acute phase proteins. Serum levels of these proteins decrease in response to inflammation and physiologic stress. Failure of these levels to increase does not mean that nutrition therapy is inadequate. Despite this knowledge, some clinicians still misuse serum protein levels to diagnose malnutrition or determine efficacy of nutrition support. Albumin and other serum proteins are prognostic indicators in that they can help predict which patients are at high risk for morbidity, mortality, and the likelihood of developing malnutrition.13,14

The Need for Nutrition Experts
The nutritional education and training of many physicians is limited. In 1985, the National Academy of Sciences found that U.S. medical schools required an average of only 21 hours of nutrition instruction and only 27% of the schools surveyed had a specific required nutrition course. In 1990, the National Nutrition Monitoring and Related Research Act specified the need for nutrition education for physicians. Over the past several years, schools have implemented some changes, but these may still not be sufficient. A 2004 survey of medical schools found that of 106 respondents, 93% required nutrition instruction, 5% offered it as optional, and 2% did not offer it. Of the schools that required nutrition instruction, total contact hours ranged from two to 70. Only 41% of the schools provided the minimum 25 hours as recommended by the National Academy of Sciences and 18% required 10 hours or less.19

The prevalence of malnutrition as determined by SGA was 69% in a Canadian tertiary care university hospital in 2005, but only two patients’ medical records included nutrition information. No correlation was found between serum albumin and malnutrition, but most fourth-year medical students and residents surveyed believed albumin and prealbumin were nutritional indicators. Fifteen of the 17 residents graduated from the affiliated medical school that included nutrition assessment in the curriculum, but only one resident reported adequate knowledge of SGA.10

A recent survey of physicians from a university medical center in Illinois indicated low levels of confidence in their knowledge of nutrition support in the ICU, although all believed that nutrition in the ICU was important. Their responses to questions about initiation and management of nutrition support showed differences from published guidelines.20

Causes of Malnutrition
Many patients are already malnourished at the point of admission, while others become malnourished during their hospital stay. Etiologies include alterations in the intake, digestion, absorption, and/or metabolism of food. Risks include GI disorders, chronic disease, malignancies, lower socioeconomic status, psychological disorders, alcohol and drug abuse, older age, and lower levels of education.8,9,21

Several disease states and acute events predispose patients to malnutrition, the degree of which is usually determined by the severity of the illness.12 The most obvious are those that prevent oral food intake, such as oral cancer, tumors or strictures in the throat or esophagus, stroke, and degenerative neurologic disorders that result in dysphagia. Trauma patients and others who are ventilator dependent rely on the timely initiation of nutrition support. Conditions such as chronic obstructive pulmonary disease, chronic infections, and cancer can result in increased metabolic demand and weight loss due to cachexia and poor oral intake.21

Patients with GI disorders are among those who are most prone to developing malnutrition. Patients with gastroparesis, gastric outlet or bowel obstruction, and motility disorders present with varied degrees of malnutrition depending on how long they have waited to seek medical care. Surgical resections of the GI tract for cancer or Crohn’s disease can result in severe maldigestion and malabsorption of nutrients, as can chronic digestive disorders such as cystic fibrosis. Gastric bypass procedures, while effective for weight loss, predispose patients to serious micronutrient deficiencies. Chronic liver disease can contribute to poor nutrient digestion and absorption, and patients with pancreatitis often present with malnutrition.21

Even for patients who can eat orally, nutritional intake often decreases during hospitalization. Patients are required to be NPO prior to many tests and procedures, as well as before and after surgery. Delays or the need for several procedures result in prolonged periods without nutrition. Patients’ appetites usually decrease during illness due to pain, nausea, weakness, and altered mood or mental status, and they can become dissatisfied with repetitive menu cycles, dietary restrictions, and the food, which may not be the type they prefer.

When used inappropriately, calorie counts can also prolong malnutrition. Those who have been eating poorly are unlikely to start eating better unless the underlying problem has been corrected; thus, nutrition interventions should sometimes be started without waiting for calorie count data.

Once the healthcare team decides to start nutrition support, it is sometimes not initiated for several days, held, or advanced so slowly that it takes several days to reach goals. Interruptions in enteral nutrition (EN) occur due to tests or procedures, GI intolerance, or loss of EN access. In many hospitals, clinicians hold EN unnecessarily for perceived “high” gastric residuals, when in fact they are not necessarily too high. According to McClave and Snider, in the 2002 North American Summit on Aspiration in the Critically Ill Patient, EN can be continued with gastric residual volumes of up to 400 to 500 milliliters when accompanied by careful evaluation for aspiration risk and signs of GI intolerance. In the University of Virginia Health System, residual volumes of greater than 300 milliliters are considered a sign of possible EN intolerance.

For delayed gastric emptying, postpyloric feeding access or use of prokinetic medications can be considered. Clinicians sometimes hold EN out of suspicion that it causes diarrhea, when in fact diarrhea is due to other factors, such as the underlying illness, altered anatomy, infection, and medications.22 PN is sometimes delayed or held due to lack of central venous access, central line infection, or PN-associated liver dysfunction.

Treatment of Malnutrition
For patients who can eat orally, between-meal snacks and liquid nutritional supplements can be helpful. According to American Society for Parenteral and Enteral Nutrition guidelines, patients who are either unable or expected to be unable to take sufficient oral nutrition for seven to 14 days are candidates for nutrition support. EN should be used if the GI tract is functional, and PN should be used only if the GI tract is not functional or cannot be accessed.12 PN is necessary in patients with prolonged ileus, complete bowel obstruction, bowel perforation, mesenteric ischemia, severe GI bleeding, inability to feed distal to a high-output enterocutaneous fistula, or short bowel syndrome with insufficient absorptive capacity.21

Refeeding risk is the most critical aspect early in the treatment of malnourished patients. It is important that clinicians initiate feedings at low calorie levels while monitoring serum electrolytes. An intracellular shift of potassium, magnesium, and phosphorus can result in dangerously low serum levels; thus, clinicians should monitor at least daily with the onset of feeding and replete electrolytes when necessary. Avoidance of excessive fluid administration is also important, especially in patients with cachexia. Provision of multivitamin or single nutrient supplements, or at least thiamin repletion, is often necessary.23

Despite the realization of hospital malnutrition more than 30 years ago, it remains a significant problem. Many illnesses or injuries for which patients are admitted to the hospital predispose them to malnutrition, as does hospitalization itself. Compared with other healthcare practitioners, RDs are the most qualified to recognize malnutrition as well as to help treat and prevent it. Prompt identification, treatment, and monitoring of malnourished patients, as well as helping to educate other healthcare professionals, will continue to make a positive impact in healthcare.

— Theresa A. Fessler, MS, RD, CNSD, is a nutrition support specialist at the University of Virginia Health System in Charlottesville and a freelance writer.


Factors Included in Subjective Global Assessment16

Weight: unintentional loss and time period of loss

Dietary intake: normal vs. decreased, type, duration, nutritional adequacy

GI symptoms for longer than two weeks: nausea, vomiting, diarrhea, anorexia

Functional capacity: working normally or suboptimally; ambulatory vs. bedridden

Disease state: degree of stress, metabolic demand

Physical signs: subcutaneous fat loss, muscle wasting, edema, ascites


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