Death prediction for patients with pneumonia and raised glucose levels

Raised blood sugar (glucose) levels on admission to hospital can predict deaths in patients with community acquired pneumonia but without pre-existing diabetes, finds a study published on bmj.com today.

The findings suggest that that patients with high glucose levels when community acquired pneumonia is diagnosed may need intensified care to reduce their risk of death.

Community acquired pneumonia is one of the leading infectious diseases in industrialised countries and a major cause of illness and death. Some studies have suggested a link between hyperglycaemia (high blood glucose levels) and death from community acquired pneumonia, but others show no clear association.

So a team of European researchers set out to examine whether glucose levels (or pre-existing diabetes) predict adverse outcomes in patients admitted to hospital with community acquired pneumonia. It is the largest trial to look at this topic in detail.

It involved 6,891 patients (average age around 60 years) admitted to hospitals and private practices in Germany, Switzerland and Austria with community acquired pneumonia between 2003 and 2009.

Information on age, gender, current smoking status and existing conditions (co-morbidity) was recorded and the severity of their pneumonia was measured using a standard test, known as the CRB-65 score. Death at 28, 90 and 180 days was calculated according to blood glucose levels on admission.

Increasing glucose levels were associated with increased mortality in all patients at 28 and 90 days. Compared to patients with normal glucose levels on admission, those with raised glucose levels on admission were at a significantly greater risk of death.

This risk increased as admission glucose levels increased.

Patients without diabetes and normal glucose levels on admission had the lowest (3%) mortality after 90 days. Patients without diabetes but with raised glucose levels on admission had a10% mortality rate, while diabetic patients had the highest (14%) mortality rate regardless of their glucose levels on admission.

The authors also point out that “mortality starts to increase at only slightly elevated levels that remain below the defined threshold for overt diabetes.”  And they conclude that glucose testing and close glucose monitoring after discharge are necessary to diagnose diabetes and to prevent further complications.