Malnutrition Isn't Just a Child's Problem: What Malawian Surgical Wards Reveal
A 2018 Malawi study found 80% of adult surgical patients were malnourished — despite normal BMI. Here's what that reveals about the myths we still believe about malnutrition.
Malnutrition in Surgical Patients: The Risk We Don't Always See
When most people hear the word "malnutrition," they picture a child with a swollen belly, thinning hair and a visibly wasted body.
That image is not wrong, but it is dangerously incomplete.
Malnutrition can affect adults too, including people who look well-nourished and are about to undergo major surgery.
A 2018 observational study conducted at Queen Elizabeth Central Hospital (QECH) in Blantyre examined the nutritional status of 25 adult patients undergoing laparotomy. The findings were striking. Only 20% of the patients were classified as well-nourished. The remaining 80% had some degree of malnutrition, with 52% moderately malnourished and 28% severely malnourished.
These were not children. They were adults undergoing surgery at a time when their bodies needed adequate nutritional reserves to cope with the stress of an operation and support recovery.
The study raises an important question: How often do we actually recognise malnutrition in surgical patients?
It also challenges several assumptions about what malnutrition looks like, where it comes from and why it matters.
Malnutrition is not just a childhood problem
Malnutrition is often discussed in the context of children, particularly because inadequate nutrition during childhood can have serious consequences for growth and development. But adults can become malnourished too.
For surgical patients, there are several possible pathways to malnutrition. Chronic illness can affect nutritional status, while inadequate food intake can lead to starvation-related malnutrition. Surgery and acute illness can make the situation even worse.
The body responds to surgical injury with a metabolic stress response. Energy expenditure increases, and the body begins breaking down muscle protein. At the same time, patients may eat less and move less during their hospital stay. Together, these factors can result in a rapid loss of lean body mass and physical function.
So malnutrition in a surgical patient is not simply a matter of whether someone has had enough food throughout their life. It can develop or worsen because of the illness and the treatment itself.
You don't have to be underweight to be malnourished
This is perhaps the most important lesson from the QECH study.
When the researchers looked at BMI, 76% of the patients had a normal weight. Only 6% were overweight, and none were classified as underweight. Yet when the patients were assessed using the Subjective Global Assessment (SGA), only 20% were considered well-nourished. The other 80% were classified as moderately or severely malnourished.
That is a remarkable difference.
BMI measures weight in relation to height, but nutritional assessment is more complicated than that. The SGA considers factors such as recent weight changes, dietary intake, gastrointestinal symptoms, functional capacity, metabolic stress and physical examination findings.
This is particularly important in hospitalised patients. Acute illness can cause changes in metabolism and fluid balance that make body weight a poor reflection of what is happening to the patient's nutritional status.
The researchers therefore noted that BMI may be less sensitive for identifying malnutrition in acutely ill and medically complicated patients.
In simple terms, a normal BMI does not necessarily mean a patient is nutritionally healthy.
Surgery itself can make nutritional status worse
A patient does not necessarily enter the operating theatre malnourished and remain in the same condition throughout their hospital stay.
Major surgery places considerable metabolic stress on the body. The response involves increased energy expenditure and breakdown of muscle protein. If nutritional intake does not keep up with these demands, the loss of lean body mass can continue.
The QECH researchers measured handgrip strength before surgery and again three days after surgery. Handgrip strength is useful as a simple measure of functional capacity and can provide an indication of changes in muscle function.
The median handgrip strength fell from 22.3 kg before surgery to 18.4 kg on the third postoperative day. The decrease was statistically significant.
Patients who were better nourished also had greater handgrip strength than those who were moderately or severely malnourished.
This matters because nutritional status was not just associated with muscle strength. Handgrip strength was also associated with postoperative complications and length of hospital stay.
Malnutrition can affect what happens after the operation
The consequences become even clearer when we look at hospital outcomes.
In the study, 72% of participants developed either an incision-wound infection or wound dehiscence. Severely malnourished patients had a median hospital stay of eight days, compared with four days among well-nourished patients.
This does not mean the study proved that malnutrition directly caused every complication. It was a small observational study, so the findings demonstrate associations rather than causation.
However, the findings are consistent with a wider body of evidence linking poor nutritional status with complications, impaired healing and longer hospital stays.
Nutrition therefore deserves to be considered part of surgical care, not something that can be dealt with only after the operation.
Are surgical patients being given enough food?
Another important finding from the study concerns the nutritional content of the hospital diet.
The standard diet at QECH consisted of porridge with sugar in the morning, followed by nsima with beans, cabbage or both for lunch and supper.
The researchers estimated that this diet provided approximately:
- 1,280 kilocalories per day
- 31.5 grams of protein per day
The estimated requirements were considerably higher, at approximately:
- 1,564 kilocalories per day
- 72 grams of protein per day
None of the patients met their estimated energy and protein requirements through the hospital diet alone.
This is important because surgical patients may actually require more nutrition, not less. The metabolic stress associated with surgery increases energy and protein requirements. Evidence-based recommendations cited in the paper encourage appropriate feeding as soon as possible after surgery when clinically appropriate.
Food in a surgical ward is therefore not simply about satisfying hunger.
It is part of the patient's recovery.
The problem is bigger than food
It would be easy to look at these findings and conclude that the solution is simply to give surgical patients more food.
It is more complicated than that.
Malnutrition can be caused or worsened by disease, inadequate intake, metabolic stress and reduced physical activity. Identifying it is therefore the first step.
At the time of the study, the researchers reported that there was no formal nutritional screening or assessment for adult inpatients at QECH. This meant that patients who might have benefited from nutritional support before surgery could go unidentified.
The paper highlights several established tools that can be used to identify patients at nutritional risk, including the Subjective Global Assessment, the Malnutrition Universal Screening Tool and the Nutrition Risk Score 2002.
The researchers also highlighted the limited availability of dietetic services and nutritional support within Malawi's government hospitals at the time of publication.
This means that addressing surgical malnutrition requires more than telling patients to eat better. It requires nutritional screening, appropriate assessment, access to adequate food and, where necessary, specialised nutritional support.
What should change?
The findings from QECH point towards several practical steps.
First, nutritional assessment should become part of routine surgical care.
A patient being admitted for surgery should not be assessed only for their surgical diagnosis and fitness for anaesthesia. Their nutritional status also matters.
Second, BMI should not be used as the only indicator of nutritional status.
The QECH study provides a particularly striking example of why. None of the patients were underweight according to BMI, yet four out of five were classified as malnourished using SGA.
Third, nutritional support should continue after surgery.
The metabolic demands of surgery do not end when the operation is over. Patients need adequate energy and protein to support recovery, maintain lean body mass and support normal physiological functions.
The bigger picture
The QECH study was small, involving only 25 patients, and it was conducted at a single hospital. The researchers themselves acknowledged these limitations and called for larger studies involving other hospitals and patient populations in Malawi.
But despite those limitations, the study raises an important issue that is easy to overlook.
Malnutrition in surgical patients can be hidden in plain sight.
The patient may not look thin.
Their BMI may be normal.
They may even appear physically well.
Yet beneath the surface, illness and surgical stress may be contributing to muscle loss and declining nutritional reserves.
The question, therefore, should not simply be whether a surgical patient looks malnourished.
The better question is:
Have we actually assessed their nutritional status?
Because surgery is only one part of recovery. The body still needs the resources to heal after the operation is over.
And sometimes, one of the most important interventions in surgical care is not another drug or another procedure.
It is making sure the patient has enough nutrition to recover.
Source
Katundu KGH, Mutafya TW, Lozani NC, Nyirongo PM, Uebele ME. An observational study of perioperative nutrition and postoperative outcomes in patients undergoing laparotomy at Queen Elizabeth Central Hospital in Blantyre, Malawi. Malawi Medical Journal. 2018;30(2):79-85.