Hospital patients who eat less than a quarter of the food they are offered or who are already malnourished are significantly more likely to die within 30 days of admission, research on more than 3000 patients in 56 Australian and New Zealand hospitals has found.
Dr Ekta Agarwal, from QUT's Institute of Health and Biomedical Innovation, said the study was believed to be the first to show that poor food intake was associated with a significantly high risk of in-hospital death rates regardless of the patients' age, nutritional status and type and severity of disease.
"We defined malnutrition as a BMI of less than 18.5 combined with a moderate or severe score on an international malnutrition screening tool," Dr Agarwal said.
"We found one in three malnourished patients ate less than 25 per cent of the offered food, and that malnourished patients were 1.5 times more likely to die in hospital within 30 days than well-nourished patients.
"When we looked at the 90-day outcome the risk factor for death increased four times for the malnourished patients.
"We also found that one in five patients classified as well-nourished also ate less than 25 per cent of the food offered.
"Even well-nourished patients who have a poor food intake during illness over a long period can become malnourished and increase their risk of infection, a longer hospital stay, readmission, and death.
"For the well-nourished patients who ate less than 25 per cent, the risk of dying in hospital within 30 days increased by more than 2.5 times. When we checked those with a 90-day stay their risk of dying in hospital doubled.
"Well-nourished patients' appetite could be affected for several reasons: the symptoms associated with their disease/condition, their treatment, the hospital environment, unappealing taste or appearance of hospital food, or mealtimes that are too early or too late for them."
Dr Agarwal said the results indicated patients' food intake should be recorded after each meal.
"Also, the patients who eat less than a quarter of the food offered should be offered a nutrition intervention," she said.
"While most malnourished patients were aged 65 years or older, poor food intake was common across all adults.
"Malnourished patients have 50 per cent longer hospital stays in comparison to well-nourished patients, which adds significantly to healthcare costs."
Dr Agarwal said Australian and New Zealand hospitals were required to code or classify their patient cases according to their diagnoses to estimate costs of treatment and burden of diseases.
"This study found that 21 of the 56 participating hospitals did not code for malnutrition at all," she said.
"Appropriate assignment of malnutrition codes to patient records is warranted to reflect the burden of malnutrition in Australian and New Zealand hospitals."
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