A study of non-diabetic patients suffering from acute illness showed those who had hyperglycaemia were more likely to go on to develop type-2 diabetes after five years.
Researchers from University Hospital Centre Rebro in Croatia suggested the temporary condition, linked to stress and inflammatory hormones released during critical illness, revealed the presence of underlying predisposition to diabetes.
They recommended that such patients should be followed up to ensure timely diagnosis.
Hyperglycaemia is often brought on by stress and inflammation during acute illness but some patients will even develop hyperglycaemia in milder disease.
Researchers proposed the occurrence of this condition could reveal a person’s underlying risk of diabetes.
They followed up 591 patients five years after hospitalisation for acute illness, and divided them into two groups: those who had suffered acute illness-related hyperglycaemia and those whose blood sugar levels remained normal.
Among patients in the normoglycaemia group, almost one in 30 patients (3.5%) developed type-2 diabetes.
But this figure was higher in the hyperglycaemia group, where one in six patients (17.1%) went on to develop diabetes.
While the authors could not confirm a causal link, they said patients in the hyperglycaemia group displayed many of the risk factors for diabetes.
The researchers wrote: ‘Whatever the underlying physiology, there is a combination of physiological factors predisposing a patient for hyperglycaemia in acute illness, during which hyperglycaemic mechanisms in stress and inflammatory responses reveal the disorder.’