Dietitians have traditionally been involved in the care of hospitalized patients. Nutritional assessment in hospitalized patients incorporates all areas of nutritional assessment--dietary, anthropometric, and biochemical. It has been noted that up to 50% of hospitalized patients are malnourished. Malnutrition in the hospital setting is defined as an unintentional weight loss of greater than 10% and serum albumin levels of less than 3.2 g/dL. Hospital malnutrition can contribute to high rates of infection, impaired wound healing, less than optimal surgical outcome, postoperative complications, longer hospital stays, and a higher risk of death.

Nutritional assessment begins with a detailed nutritional history that includes clinical, dietary, socioeconomic, and family issues. Areas of interest include present and past illnesses, family illness history, food allergies or intolerance, medications, nutritional supplements, over-the-counter medications, alcohol use, work environment, and education level.

Clinicians sometimes use standardized protocols in their assessments. One such protocol is the Likelihood of Malnutrition Score (LMS). This includes the parameters: serum folate, serum vitamin C, triceps skinfold thickness, serum albumin, absolute lymphocyte count, hematocrit, mid-arm muscle circumference, and body weight. The LMS has been shown to correlate with length of hospital stay. The Prognostic Nutritional Index (PNI) incorporates serum albumin, serum transferrin, delayed skin hypersensitivity, and triceps skinfold thickness. The PNI has been shown to correlate with postoperative complications and mortality.

Functional assessment can also be used to help assess nutritional status. One can test physiologic function by examining overall activity, exercise tolerance, grip strength, respiratory function, wound healing, and plasma albumin concentration.