What is the definition of Subjective Global Assessment (SGA)?

From the Guidelines

The subjective global assessment (SGA) is a valuable and recommended tool for evaluating nutritional status in patients, particularly those with chronic conditions or undergoing medical treatments, due to its simplicity, reproducibility, and association with patient outcomes, as evidenced by the CANUSA study 1. The SGA involves a comprehensive assessment of a patient's nutritional health through medical history and physical examination, including evaluation of weight changes, dietary intake, gastrointestinal symptoms, functional capacity, and physical signs of malnutrition such as muscle wasting and loss of subcutaneous fat.

• The assessment is typically classified into three categories: well-nourished, moderately malnourished or suspected of being malnourished, or severely malnourished, which helps healthcare providers determine appropriate nutritional interventions.
• The SGA is valuable because it doesn't require laboratory tests or specialized equipment, making it practical for various clinical settings, and its reliability comes from its holistic approach, considering both objective physical findings and subjective patient-reported information.
• A modified 7-point scale, as used in the CANUSA study, is recommended for assessing nutritional status in patients, particularly those undergoing continuous ambulatory peritoneal dialysis (CAPD), as it may provide greater sensitivity and predictive power than the original 3-point ordinal scale 1. The use of SGA has been validated in various studies, including the CANUSA study, which showed that a higher SGA score was associated with a lower relative risk of death and fewer hospitalized days per year 1.
• The SGA can be applied by any healthcare professional following a short training period, making it a practical tool for clinical settings.
• The assessment's ability to detect changes in nutritional status and its association with patient outcomes make it a useful tool for identifying patients who may benefit from nutritional support before their condition deteriorates significantly.

From the Research

Definition and Purpose of Subjective Global Assessment

• The Subjective Global Assessment (SGA) is a nutrition assessment tool that evaluates a patient's history and physical examination to diagnose malnutrition 2.
• The SGA is used to identify patients who are likely to benefit from nutrition intervention and to distinguish malnutrition from other wasting conditions such as cachexia and sarcopenia 2.

Reliability and Validity of SGA

• The SGA is a reliable and valid tool that predicts morbidity and mortality associated with malnutrition 2, 3.
• The SGA has been shown to be sensitive and specific in identifying patients with malnutrition, although its reproducibility depends on the experience of the caregiver administering it 3.
• The SGA has been validated against more objective parameters such as visceral proteins and body composition, although its sensitivity in detecting early malnutrition may be limited 3, 4.

Clinical Applications of SGA

• The SGA is widely used in clinical practice to evaluate the nutritional status of patients with various conditions, including kidney disease, AIDS, cancer, and aging 3.
• The SGA has been shown to be a useful tool for screening hospital malnutrition, with a high degree of correlation with anthropometric and biochemical parameters 4.
• The SGA is one of several malnutrition diagnostic tools available, including the Mini Nutritional Assessment and the Global Leadership Initiative on Malnutrition criteria 5.

Use of SGA in Clinical Practice

• The SGA has been used in various patient populations, including surgical and oncology patients, and remains a reliable and efficient method of nutrition assessment 6.
• The SGA can be used to identify patients who are at risk of malnutrition and to guide nutrition intervention, with the goal of improving patient outcomes and reducing healthcare costs 4.