Nutritional screening in patients on hemodialysis: is subjective global assessment an appropriate tool?

Malnutrition is common in patients with chronic renal failure and should be screened for systematically. Subjective global assessment (SGA) is frequently used, but it is time-consuming. The aim of this study was to assess the sensitivity of SGA as a screening tool for malnutrition compared with the measurement of body mass index (BMI) and serum albumin combined with a history of unintentional weight loss.

This was a cross-sectional study.

The study was undertaken in two hospital hemodialysis units.

A total of 141 patients on hemodialysis were studied. Nutritional assessment was undertaken with a seven-point SGA, measurement of height, weight and serum albumin, and a record of unintentional weight loss.

Patients were considered to be at risk of malnutrition if any of the following three criteria were met: a serum albumin less than 35 g/L, a BMI less than 18.5, and unintentional weight loss of edema free weight greater than 10% in the past 6 months. A diagnosis of malnutrition was made if the SGA score was between 1 and 5.

A total of 41 patients had either a serum albumin less than 35 g/L or a BMI less than 18.5 or unintentional weight loss of edema free weight of more than 10% in the past 6 months. Of these 41 patients, 29 had a serum albumin less than 35 g/L, 9 had a BMI less than 18.5, and 15 had unintentional loss of edema free weight greater than 10% in the past 6 months. Thirteen patients were judged by SGA to be mild to moderately malnourished. All 13 were identified by serum albumin, BMI, or weight loss.

In this study, measurement of SGA did not diagnose malnutrition in any patients in whom this had not already been potentially identified by measurement of serum albumin, BMI, and a history of weight loss. SGA did not therefore increase the sensitivity of nutritional screening in this cohort.